Medcoffee 2 Flashcards

Question

least mediated by local metabolites? brain blood vessels kidney skin heart

Answer 1

D) Reason Skin is richly supplied by the extensive distribution of the sympathetic nerve fibers. Its blood flow is least affected hy local metabolites rather is mediated by sympathetic stimulation or inhibition.

Answer 2

E) Reason Route Values of the different Deep Tendon reflexes are as: Bicep C5-6, Tricep: C3-4, Supinator C6-7, Knee Jerk L3-4, Ankle S1 and Jaw jerk V5 (CN V).

Answer 3

A) Reason ELISA/Western blot tests look for antibodies to viral proteins; these tests often are falsely negative in the first 1–2 months of HIV infection till you isolate the patient. It is falsely positive initially in babies born to infected mothers (anti-gp120 crosses placenta).

Answer 4

B) Reason At FRC, inward pull of lung is balanced by outward pull of chest wall, and system pressure is atmospheric

Answer 5

B) Reason In our brain, right side of body is controlled by left hemisphere and vice versa. So right side of body weakness is the feature of left sided lesion in brain and vice versa.

Answer 6

E) Reason When A blood group is donated to a patient with blood group AB, Anti-B Antibodies of A blood group will damage the B antigens of AB blood group laeding to mismatch reaction.

Answer 7

D) Reason Staph make catalase because they have more “staff.” Bad staph (aureus) make coagulase and toxins. Forms fibrin clot around self leading to abscess.

Answer 8

E) Reason Minimum amount (volume) of urine output that can prevwnt the adverse level of nitrogeneous wastes is 0.5ml/kg/hr that comes to be about 500-800ml in a person of 50-70kg.

Answer 9

D) Reason Obstructive lung volumes > normal (inc. TLC, inc. FRC, inc.RV); restrictive lung volumes < normal. In both obstructive and restrictive, FEV1 and FVC are reduced. In obstructive, however, FEV1 is more dramatically reduced compared to FVC, resulting in a decreased FEV1/FVC ratio.

Answer 10

C) Reason The pterygopalatine ganglion is a parasympathetic ganglion, which is suspended from the maxillary nerve in thepterygopalatine fossa (parapharyngeal fossa). It is secretomotor to the lacrimal andthe nasal glands .

Answer 11

E) Reason Factor X: Stuart factor; Stuart-Prower factorFactor XI: Plasma thromboplastin antecedent (PTA); antihemophilic factor CFactor XII: Hageman factorFactor XIII: Fibrin-stabilizing factorPrekallikrein: Fletcher factorHigh-molecular-weight Fitzgerald factor; HMWK.

Answer 12

E) Reason Giant cell Arteritis: Clinical manifestations include: (1) Malaise and fatigue (2) Headache or claudication of the jaw (3) Tenderness, absent pulse, and palpable nodules along the course of the involved artery (4) Visual impairment, especially with involvement of the ophthalmic artery (5) Polymyalgia rheumatica, a complex of symptoms.

Answer 13

E) Reason • Dorsiflexion (toes pointing upward): Tibialis anterior, extensor hallucis longus, extensor digitorum longus, and peroneus tertius muscles

Answer 14

A) Reason 1. Non-proliferative: Manifestations include micro aneurysms, dilation of veins, hemorrhages, soft (cottonwool) exudates (microinfarcts), and hard exudates (deposits of protein that have leaked from damaged capillaries) , all of which can be viewed with the ophthalmoscope. b. The retinopathy also includes increased capillary permeability, edema, and diffuse thickening of basement membranes (microangiopathy) . c. The disorder is related to the duration of the disease, occurring in most patients with diabetes mellitus after 10 years. 2. Proliferative retinopathy:. New retinal vessel formation (neovascularization) and fibrosis, both extending into the vitreous, is characteristic.

Answer 15

E) Reason The receptors for pain are free nerve endings in the skin, muscle, and viscera.■ Neurotransmitters for nociceptors include substance P. Inhibition of the release of substance P is the basis of pain relief by opioids.

Answer 16

E) Reason External oblique aponeurosis, reinforced laterally by origin of the internal oblique from the inguinalligament. Posteriorly, its upper fibers interdigitate with serratus anterior

Answer 17

D) Reason Estrogens are produced by the interplay of the fetal adrenal gland and the placenta. The fetal adrenal gland synthesizes dehydroepiandrosterone-sulfate (DHEA-S), which is then hydroxylated in the fetal liver.

Answer 18

C) Reason The central most portion of the diaphysis of larger long bones is filled with bone marrow, either hematopoietically active or fatty, without intervening bony trabeculae.

Answer 19

C) Reason Inflammation important in pathogenesis. Endothelial cell dysfunction causes macrophage and LDL accumulation leads to foam cell formation- fatty streaks- smooth muscle cell migration (involves PDGF and FGF), proliferation, and extracellular matrix deposition lead to fibrous plaque leads to complex atheromas

Answer 20

B) Reason In Athletes, there is physiological polycythemia that causes dec. heart rate. But at rest heart rate decreases more and hence stroke volume increases in order to maintain the cardiac output. (Cardiac Output= stroke volume x heart rate).

Answer 21

E) Reason Ventromedial area: It contains Satiety. Destruction (e.g.craniopharyngioma) leada to hyperphagia. Stimulated by leptin.

Answer 22

A) Reason SA node “pacemaker” inherent dominance with slow phase of upstroke.AV node—100-msec delay—atrioventricular delay; allows time for ventricular filling

Answer 23

B) Reason In an acute setting, Warfarin toxicity is treated with FFP and in prolong management, it is treated with vit. K.

Answer 24

C) Reason Increased protein content, cloudy. Due to malignancy, pneumonia, collagen vascular disease, trauma (occurs in states of increased vascular permeability). Must be drained in light of risk of infection.

Answer 25

D) Reason Autograft From self.Syngeneic graft From identical twin or clone.Allograft From nonidentical individual of same species.Xenograft From different species.

Answer 26

E) Reason MECHANISM: Irreversibly inhibits cyclooxygenase (both COX-1 and COX-2) enzyme by covalent acetylation. Platelets cannot synthesize new enzyme, so effect lasts until new platelets are produced: inc. bleeding time, dec. TXA2 and prostaglandins. No effect on PT or PTT

Answer 27

E) Reason CLINICAL USE: CHF (increases contractility); atrial fibrillation (decreases conduction at AV node and depression of SA node). Patient in this scenario is a case of atrial fibrillation.

Answer 28

D) Reason Consequences (MAD HUNGER):Metabolic Acidosis, Dyslipidemia (especially increased triglycerides), HyperkalemiaUremia—clinical syndrome marked by inc. BUN and inc. creatinineNausea and anorexia

Answer 29

A) Reason After birth, the umbilical veins are closed, and the remnant in adults is the Ligamentum teres of the liver

Answer 30

A) Reason Homonemous hemianopia is contralatral half eye vision vision and is due to the lesion of occipital lobe.

Answer 31

C) Reason Systolic ejection—period between aortic valve opening and closing, at end of this phase, the aortic pressure becomes maximum

Answer 32

A) Reason Anencephaly Malformation of anterior neural tube resulting in no forebrain, open calvarium (“frog-like appearance”). Clinical findings: increased AFP; polyhydramnios (no swallowing center in brain). Associated with maternal diabetes (type I). Maternal folate supplementation inc. risk.

Answer 33

B) Reason The tuberosity lies infront of and below the medial malleolus, and it attaches tothe main part of the tibialis posterior tendon (posterior to medial maleolus).

Answer 34

D) Reason Lateral area: Hunger. Destruction causes anorexia, failure to thrive (infants). Inhibited by leptin.

Answer 35

D) Reason Obstruction to secretion of any body fluid is trigger Factor for inflammation, in glandular organs, obstruction to secretions can lead to self digestion or Autophagy of the cell- Apoptosis

Answer 36

D) Reason Striking exophthalmos (protrusion of the eyes), possibly due to autoimmune (Thyroid Stimulating Igs) mechanisms and independent of thyroid hyperfunction, is characteristic. Manifestations include the signs and symptoms of hyperthyroidism.

Answer 37

A) Reason Lucid interval after traumatic brain injury are the features of Epidural hematoma (middle meningeal artery rupture)

Answer 38

E) Reason Classic presentation of SLE: rash, joint pain, and fever, most commonly in a female of reproductive age and African descent.Libman-Sacks endocarditis—wart-like vegetations on both sides of valve.Lupus nephritis (type III hypersensitivity reaction

Answer 39

D) Reason In most people, the inferior cervical ganglion is fused to thefirst thoracic ganglion to form the stellate ganglion. It is located between the transverse process of the seventh cervical vertebra and the neck of the first rib.

Answer 40

C) Reason Nucleus pulposus is an inner soft, elastic, compressible material thatfunctions as a shock absorber for external forces placed on the vertebral column. The nucleus pulposus is the postnatal remnant of the notochord.

Answer 41

A) Reason SOURCE: Parafollicular cells (C cells) of thyroid. FUNCTION: bone resorption of Ca2+. It opposes the effect of PTH

Answer 42

D) Reason The pretracheal layer is a thin layer that is attached above tothe laryngeal cartilages . Infection between deep cervical fascia and pre tracheal fascia can affect the anterior mediastinum.

Answer 43

A) Reason Anaphylactic and atopic—free antigen cross links IgE on presensitized mast cells and basophils, triggering immediate release of vasoactive amines that act at postcapillary venules (i.e., histamine). Reaction develops rapidly after antigen exposure because of preformed antibody

Answer 44

B) Reason Acute pericarditis: Commonly presents with sharp pain aggravated by inspiration, and relieved by sitting up and leaning forward. Presents with friction rub. ECG changes include widespread ST-segment elevation and/or PR depression. Suppurative/purulent Type: usually caused by bacterial infections (e.g Pneumococcus, Streptococcus). Rare now with antibiotics.

Answer 45

A) Reason Bronchopulmonary segments are the anatomic, functional, and surgical units of the lungs. Each lobar (secondary) bronchus, which passes to a lobe of the lung, gives offbranches called segmental (tertiary) bronchi

Answer 46

B) Reason In rest of all conditions (except FFP) GVHD occurs Graft-versus-host Reaction/disease:Onset Varies. Grafted immunocompetent T cells proliferate in the immunocompromised host and reject host cells with “foreign” proteins leading to severe organ dysfunction.

Answer 47

C) Reason Enlargement of air spaces, decreased recoil,increased compliance, decreased DLCO resulting from destruction of alveolar walls.Two types:1. Centriacinar—associated with smoking B.2. Panacinar—associated with α1-antitrypsin deficiency

Answer 48

B) Reason Creatinine is the end product of the muscle metabolism that is the reason that Creatinine increases in myositis and other cases of muscle breakdown

Answer 49

B) Reason Glucokinese is an enzyme that phosphorylates glucose to glucose-6-P, it present in liver β cells unlike that of hexokinase that is present in muscles but not in liver or pancreas

Answer 50

E) Reason Leiomyoma (fibroid):A Most common tumor in females. Often presents with multiple discrete tumors A. Increased incidence in blacks. Benign smooth muscle tumor; malignant transformation is rare. Estrogen sensitive—tumor size increased with pregnancy and decreased with menopause.

Answer 51

E) Reason Transitional epithelium is a stratified epithelium in which the shape of the surface cells changes (undergoes transitions) depending on the degree of stretch. This epithelium has no basement membrane.When a transitional epithelium is not stretched (for example in an empty bladder) the cells of the surface layers are large and rounded.

Answer 52

C) Reason Acute viral hepatitis is characterized by jaundice and extremely high elevations of serum aspartate and alanine aminotransferases. Hyperbilirubinemia is also there

Answer 53

A) Reason • Among the muscles of the anterior compartment, Iliopsoas, rectus femoris, sartorius, and adductormuscles, most prominent and superficial muscle is rectus femoris that is injured first in avulsion injury.

Answer 54

B) Reason Posterior interventricular artery: It is the terminal distribution of the right coronary artery and courses in the posterior interventricular sulcus to supply parts of the right and left ventricles and, importantly, the posterior third of the interventricular septum.

Answer 55

C) Reason M. gravis is the most common NMJ disorder, PATHOPHYSIOLOGY: Autoantibodies (IgGs) to postsynaptic ACh receptors. CLINICAL Manifestations are Ptosis, diplopia, weakness.Worsens with muscle use

Answer 56

B) Reason Dysplasia and carcinoma in situ:Disordered epithelial growth; begins at basal layer of squamocolumnar junction (transition zone) and extends outward

Answer 57

C) Reason Lesions in somatosensory cortex result in impairment of all somatic sensations on the opposite side of the body, including the face and scalp.

Answer 58

D) Reason For the diagnosis of acute and congenital infections, an immunofluorescence assayfor IgM antibody is used. IgM is used to diagnose congenital infection, because IgG can be maternal in origin.

Answer 59

D) Reason The epithelial lining of the airway is composed of ciliated cells (goblet and basal cells are absent in the terminal bronchioles) and an additional type called the Clara cell.

Answer 60

A) Reason Features of obstruction of anterior communicatin Artery: Vomiting, vertigo, nystagmus; decreased pain and temperature sensation from ipsilateral face and contralateral body; dysphagia,hoarseness, decreased gag reflexipsilateral Horner syndrome; ataxia, dysmetria.

Answer 61

A) Reason There is only one anterior spinal artery formed bythe union of branches from each vertebral artery. Vertebral artery is the main supply of the spinal cord.

Answer 62

E) Reason Left anterior descending artery (LAD)—supplies anterior 2/3 of interventricular septum, anterior papillarymuscle and anterior surface of left ventricle. LAD is the most common cardiac artery to be occluded.

Answer 63

E) Reason Long QT interval:1. Bradycardia2. Hypocalcemia3. Acute MI4. Acute myocarditis5. Cerebrovascular accident6. Hypertrophic cardiomyopathy7. Hypothermia

Answer 64

B) Reason The phrenic nerve is the only motor nerve supply to thediaphragm. It also sends sensory branches to the pericardium, the mediastinal parietal pleura, and the pleura and peritoneum covering the upper m and lower surfaces of thecentral part of the diaphragm.

Answer 65

E) Reason Causes are: Decreased iron due to chronic bleeding (GI loss, menorrhagia), malnutrition/absorption disorders or increased demand (e.g., pregnancy)decreased final step in heme synthesis.

Answer 66

D) Reason Mobitz type I (Wenckebach):Progressive lengthening of the PR interval until a beat is “dropped” (a P wave not followed by a QRS complex). Usually asymptomatic.

Answer 67

E) Reason Sulfonamides interfere with folic acid synthesis by preventing addition of para-aminobenzoic acid (PABA) into the folic acid molecule through competing for the enzyme dihydropteroate synthetase. Sulfonamides are therefore bacteriostatic and inhibit growth and multiplication of bacteria, but do not kill them. Humans, in contrast to bacteria, acquire folate (vitamin B9) through the diet.

Answer 68

D) Reason Doctor and Patient relationship is very special and based on absolute privacy and mutual trust

Answer 69

C) Reason Sudden loss of vision commonly occurs in central retinal artery occlusion and central retinalvein occlusion, retinal detachment, papillitis, acute congestive glaucoma, emboli, vitreous haemorrhage,etc.

Answer 70

A) Reason MELANOMA:A. Malignant neoplasm of melanocytes; most common cause of death from skin cancer B. Risk factors are based on UVB-induced DNA damage and include prolonged exposure to sunlight, albinism, and xeroderma pigmentosum

Answer 71

D) Reason Serratus anterior Insertion is to the Medial border and inferiorangle of the scapula where it stabilizes the bone

Answer 72

A) Reason Processus vaginalis(evagination of peritoneum):Forms tunica vaginalis as its remnant in male

Answer 73

E) Reason Risk factors: inc. estrogen exposure, inc. total number of menstrual cycles, older age at 1st live birth, obesity (inc. estrogen exposure as adipose tissue converts androstenedione to estrone), BRCA1 and BRCA2 gene mutations, African American ethnicity (inc. risk for triple inc. breast cancer).

Answer 74

A) Reason Renal fascia: This is a condensation of areolar tissue outside the perirenal fat. It encloses the kidneys and thesuprarenal glands

Answer 75

D) Reason he maxillary nerve is purely sensory. It leaves the skull through the foramen rotundum and crosses thepterygopalatine fossa to enter the orbit through the inferiororbital fissure. It then continues as the infraorbital nerve in the infraorbital groove, and it emerges on the facethrough the infraorbital foramen. It gives sensory fibers tothe skin of the face and the side of the nose.

Answer 76

E) Reason Asthma: Bronchial hyperresponsiveness causes reversible bronchoconstriction. Smooth muscle hypertrophy, Curschmann spirals (shed epithelium forms mucus plugs), and Charcot Leyden crystals (formed from breakdown of eosinophils in sputum).

Answer 77

B) Reason A first step in the invasion of malignant cells through an epithelium results from a loss of expression of cadherins and loss of keratin that weakens the epithelium.

Answer 78

C) Spinothalamic and dorsal columns/medial lemniscus:Take Pain and temperature; pressure, touch, vibration, and proprioceptionDestination to 1° somatose nsory cortex

Answer 79

B) Reason Phase 2 = plateau (corresponds to ST Segment): Ca2+ influx through voltage-gated Ca2+ channels balances K+ efflux. Ca2+influx triggers Ca2+ release from sarcoplasmic reticulum and myocyte contraction.

Answer 80

E) Reason • Lateral rotation:Infraspinatus, teres minor, and posteriorfibers of deltoid muscles.• Medial rotation: Subscapularis, latissimus dorsi, teresmajor, and anterior fibers of deltoid muscles

Answer 81

E) Reason The hippocampal formation extends along the floor of the inferior horn of the lateral ventricle in the temporal lobe and includes the hippocampus, the dentate gyrus, the subiculum, and adjacent entorhinal cortex.

Answer 82

B) Reason Function: Compresses abdominal contents and flexes vertebral column, is also an accessory muscle of expiration especially forceful expiration

Answer 83

C) Reason Overdose:causes respiratory alkalosis initially, which is then superimposed by metabolic acidosis (by increased urinary excretion).

Answer 84

C) Reason FUNCTION: Converted to pyridoxal phosphate, a cofactor used in transamination (e.g., ALT and AST), decarboxylation reactions, glycogen phosphorylase.

Answer 85

A) Reason Tetanus can be prevented by Toxoid.

Answer 86

E) Reason Type III: SLEPolyarteritis nodosaPoststreptococcal glomerulonephritisSerum sicknessArthus reaction (e.g., swelling and inflammation following tetanus vaccine).

Answer 87

A) Reason The trigeminal ganglion lies in middle cranial fossa within a pouchof dura mater called the trigeminal cave. Middle cranial fossa pain is due to pressure of this ganglion on minininges.

Answer 88

D) Reason In the carotid sheath, the artery is related laterally to the internal jugular vein; the vagus nerve lies between these two structures.

Answer 89

C) Reason Type III: SLEPolyarteritis nodosaPoststreptococcal glomerulonephritis, Serum sicknessArthus reaction (e.g., swelling and inflammation following tetanus vaccine)

Answer 90

C) Reason The prototype is retinoblastoma, an intraocular childhood tumor (causing unilateral blindness) caused by inactivation of the Rb gene. The "two-hit" hypothesis of Knudson holds that two mutagenic events are required to induce alterations on both chromosomes.

Answer 91

C) Reason Normal splitting is due to delayed closure of pulmonic valve than aortic valve.decreased pulmonary impedance ( increased capacity of the pulmonary circulation) also occurs during inspiration, which contributes to delayed closure of pulmonic valve.

Answer 92

A) Reason GROSS MORPHOLOGY: Transmural inflammation, fistulas. Cobblestone mucosa, creeping fat, bowel wall thickening (“string sign” on barium swallow x-ray), linear ulcers, fissures.

Answer 93

C) Reason In this scenario, the most specific marker that is cardioselective (troponin and ECG ) are normal while CK can be raiswd in muscular pain.

Answer 94

A) Reason When the Na is reabsorbed in DCTs, it causes fluid retention in the body and thus leading to increased plasma volume.

Answer 95

D) Reason Each connexon consists of 6 connexin molecules. Unlike other intercellular junctions, gap junctions are not associated with any cytoskeletal filament and Golgi complex.

Answer 96

A) Reason Most common is OCP . Most initial is endothelial injury.

Answer 97

B) Reason Unlike the muscrinic blockers, the ganglion blockers interrupt sympathetic control of venous tone, they cause marked venouspooling; postural hypotension is a major manifestation of this effect.

Answer 98

A) Reason TOXICITY: Nausea, headache, facial flushing, coagulopathy, hypotension, abdominal pain.

Answer 99

D) Reason Yellow fever virus: A flavivirus (also an arbovirus) transmitted by Aedes mosquitoes. Virus has a monkey or human reservoir

Answer 100

E) Reason Polyarteritis nodosa: Young adults.Hepatitis B seropositivity in 30% of patients.Fever, weight loss, malaise, headache.

Answer 101

A) Reason A total of 400-500 cc of CSF is produced per day; ventricles and subarachnoid space contain 90-150 cc, so all of CSF is turned over 2-3 times per day. In comparison with plasma, it has less glucose, more proteins, less cells and low pH.

Answer 102

B) Reason Hematoxylin is a blue dye which stains basophilic substrates that are the acidic cellular components such as DNA and RNA. Hematoxylin stains nuclei blue, and may tint the cytoplasm of cells with extensive mRNA (proteins synthesis) in their cytoplasm.

Answer 103

B) Reason Difference between the Anaphylactic shock and hypovolumic shock is the cardiac output, it is decreased in hypovolumic shock and increased in anaphylactic shock.

Answer 104

E) Reason The acrosome, which is located over the anterior half of the nucleus, is derived from the Golgi complex of the spermatid and contains several hydrolytic enzymes.

Answer 105

C) Reason The oculomotor nerve, therefore, is entirely motor. It isresponsible for lifting the upper eyelid; turning the eye upward, downward, and medially; constricting the pupil; andaccommodating the eye.

Answer 106

D) Reason Chronic hepatitis is characterized by symptoms that last > 6 months. l. Inflammation predominantly involves portal tract and adjacent lobules and necrotic foci 2. Risk of progression to cirrhosis

Answer 107

E) Reason Respiratory distress is due to diaphragm paralysis caused by Phrenic nerve injury at cervical C3-C4 spinal segments.

Answer 108

A) Reason Hemisection: Ipsilateral loss of all sensation at the level of the lesion Ipsilateral LMN signs (e.g., flaccid paralysis) at the level of the lesionIf lesion occurs above T1, patient may present with Horner syndrome due to damage of oculosympathetic pathway

Answer 109

A) Reason Alpha 1 receptors are Present at blood vessels and they maintain the total periphral resistance due the state of vasoconstriction or Vasodilation.

Answer 110

D) Reason Growth factor Receptors: ■ Hormone binds to the extracellular side of the receptor. As many of the growth factor receptors are located in cell membrane.

Answer 111

D) Reason Barrett esophagus: Glandular metaplasia—replacement of nonkeratinized (stratified) squamous epithelium with intestinal epithelium (nonciliated columnar with goblets cells) in the distal esophagus

Answer 112

D) Reason It is a normal notation the antioxidants are regarded as protective against the carcinogenesis. Orange contains vit. C that is a strong antioxidant.

Answer 113

C) Reason The anticholinergicdrugs dicyclomine (antimuscrinic) and hyoscyamine are used as antispasmodics to relieve abdominal pain; however,their efficacy has not been convincingly demonstrated

Answer 114

E) Reason ■ Sensory information (Pco2, lung stretch, irritants, muscle spindles, tendons, and joints) is coordinated in the brain stem.■ The output of the brain stem controls the respiratory muscles and the breathing cycle.

Answer 115

E) Reason Functions of Corticosteroids: Increases Insulin resistance (diabetogenic)Increases Gluconeogenesis, lipolysis, and proteolysisDecreases Fibroblast activity (causes striae)Decreases Inflammatory and Immune responses:

Answer 116

D) Reason Neurovascular Structures related to the head of the fibula are anterior tibial artry and common peroneal nerve that can be damaged during the fractures

Answer 117

B) Reason Thrombotic thrombocytopenic purpura (TIP) (1) Characteristics include platelet-derived hyaline microaggregates in small vessels, thrombocytopenia, and microangiopathic hemolytic anemia.

Answer 118

E) Reason Forgut Derivatives Esophagus, Stomach, Duodenum (first and second parts), Liver, Pancreas, Biliary apparatus, Gallbladder are supplied by the Superior mesenteric artery.

Answer 119

D) Reason HIV PCR/viral load tests determine the amount of viral RNA in the plasma. High viral load associated with poor prognosis. Also use viral load to monitor effect of drug therapy. It also determines the viral load in new born uptill age of 18 months

Answer 120

E) Reason RER is a single, lipid bilayer continuous with the outer nuclear membrane. It is organized into stacks of large flattened sacs called cisternae, nuclear cisternae to the nuclear membrane.

Answer 121

E) Reason Metoprolol is a cardiac selective beta blockers that acts centrally on heart and least on blood vessels and hence has no Vasodilation property.

Answer 122

B) Reason The axis (C2) is the point of articulation where the head turns on the neck, providing an “axis of rotation” through the odontoid.

Answer 123

A) Reason Giardia lamblia:Giardiasis: bloating, flatulence, foul-smelling, fatty diarrhea (often seen in campers/hikers)—think fat-rich Ghirardellichocolates for fatty stools of Giardia. Villous atrophy on microscopy. Treated with metronidazole.

Answer 124

D) Reason Arterial blood gases are examined in the fresh sample of an arterial blood with a heparanized syringe.

Answer 125

D) Reason Limbic system Collection of neural structures involved in emotion, long-term memory, olfaction, behavior modulation, and autonomic nervous system function.

Answer 126

D) Reason In an any medical, the chances of complications are reduced by better management as well as high level of professional competence.

Answer 127

E) Reason Tumor markers Tumor markers should not be used as the 1° tool for cancer diagnosis. They may be used to monitor tumor recurrence and response to therapy, but definitive diagnosis can be made only via biopsy

Answer 128

E) Reason Direct actions of growth hormone(a) ↓ glucose uptake into cells (diabetogenic)(b) ↑ lipolysis(c) ↑ protein synthesis in muscle and ↑ lean body mass(d) ↑ production of IGF.

Answer 129

E) Reason Decreased Colloid osmotic pressure: Decreased plasma protein concentrationSevere liver disease (failure to synthesize proteins)Protein malnutritionNephrotic syndrome (loss of protein in urine).

Answer 130

E) Reason Ketorolac is only contraindicated in asthmatic if patient also has known aspirin allergy, otherwise is best post-Op analgesia.

Answer 131

B) Reason In addition, binding of CO to hemoglobin increases the affinity of remaining sites for O2, causing a shift of the curve to the left

Answer 132

B) Reason Supination: Biceps (radial nerve) and supinator (muskulosketal nerve) muscles. This movement returns the pronated hand to the anatomic positionso that the palm faces anteriorly and the thumb lies on thelateral side.

Answer 133

A) Reason Adenylate cyclase mechanism 1. Hormone binds to a receptor in the cell membrane (step 1).2. GDP is released from the G protein and replaced by GTP (step 2), which activates the G protein. The G protein then activates or inhibits adenylate cyclase. If the G protein is stimulatory (Gs), then adenylate cyclase will be activated

Answer 134

D) Reason Epinephrine is stress hormone that is secreted by the adrenal medulla in case of stressful conditions by the activation of sympathetic nicotinic ganglionic receptors.

Answer 135

B) Reason Functions of Bile salts: Digestion and absorption of lipids and fat-soluble vitaminsCholesterol excretion (body’s only means of eliminating cholesterol) Antimicrobial activity (via membrane disruption)

Answer 136

A) Reason • Subarachnoid space lies between the arachnoid and pia mater containing CSF: site of subarachnoid hemorrhage (described later).

Answer 137

C) Reason Midazolam is widely used adjunctively with inhaled anesthetics and intravenous opioids. Theonset of its CNS effects is slower than that of thiopental, and has shortest duration of action.

Answer 138

A) Reason Diagnostic test of T.B. is Pleural Biopsy

Answer 139

D) Reason Lesion at S2-S4 causes atonic bladder

Answer 140

D) Reason Prolactin—induces and maintains lactation and decreases reproductive function. Oxytocin—assists in milk letdown; also promotes uterine contractions.

Answer 141

D) Reason CK-MB is is non-specific enzyme that can also be increased in stress, muscle and other tissue disorder, but troponin is cardiac specific enzyme.

Answer 142

C) Reason In 2nd week: • The embryoblast differentiates into the epiblast and hypoblast, forming a bilaminar embryonic disk. • The epiblast forms the amniotic cavity and hypoblast cells migrate to form the primary yolk sac.

Answer 143

C) Reason TOXICITY Hyperchloremic metabolic acidosis, inc. plasma HCO3, paresthesias, NH3 toxicity, sulfa allergy

Answer 144

A) Reason Isovolumic ventricular relaxation, Ventricular volume is constant (isovolumetric) because all of the valves are closed.■ The “blip” in the aortic pressure tracing occurs after closure of the aortic valve and is called the dicrotic notch, or incisura.

Answer 145

B) Reason Cardiac cycle = 60 sec/number of beats = 60/225 = 0.26 sec

Answer 146

C) Reason (1) It increases thirst and therefore water intake.(2) It causes vasoconstriction of the arterioles, thereby increasing TPR and arterial pressure

Answer 147

E) Reason ■ reflects the time required for excitation to spread throughout cardiac tissue.■ depends on the size of the inward current during the upstroke of the action potential. The larger the inward current, the higher the conduction velocity.■ is fastest in the Purkinje system due to less number of myofibrils.

Answer 148

B) Reason • Parotid nodes: Situated on usually superficially or within the parotid salivarygland. They receive lymph from the scalp above theparotid gland, the eyelids, the auricle, and the external auditory meatus.

Answer 149

E) Reason TOXICITY:Bleeding, teratogenic, skin/tissue necrosis A, drug-drug interactions ( Pulmonary edema with quinolones).

Answer 150

A) Reason Behind and below the deltoid tuberosity isa spiral groove, in which the radial nerve lies. As it supplies extensors of wrist that is why loss of wrist extension due to radial nerve injury.

Answer 151

A) Reason Widespread activation of clotting leads to a deficiency in clotting factors, which creates a bleeding state.Causes: Sepsis (gram-negative), Trauma, Obstetric complications, acute Pancreatitis, Malignancy, Nephrotic syndrome,

Answer 152

A) Reason Right lung is more common site for inhaled foreign body because the right main stem bronchus is wider and more vertical than the left.

Answer 153

E) Reason In 3rd trimester of pregnancy, gravid utrus pushes causes upward push of the diaphragm and decreases tidal volume and hence increases respiratory rate and dec. O2 saturation.

Answer 154

B) Reason Pia mater tightly invests the surfaces of the brain and cannot be dissected away, having the same relationship with the brain extends into sulci as well as spinal pia mater.

Answer 155

B) Reason The Cushing reaction is an example of the response to cerebral ischemia. Increases in intracranial pressure cause compression of the cerebral blood vessels, leading to cerebral ischemia and increased cerebral Pco2. The vasomotor center directs an increase in sympathetic outflow to the heart and blood vessels, which causes a profound increase in arterial pressure.

Answer 156

B) Reason Posterior descending/interventricular artery (PDA)— a branch of RCA supplies posterior 1/3 of interventricular septum and posterior walls of ventricles

Answer 157

C) Reason Iron is Absorbed as Fe2+ in duodenum.Folate is Absorbed in jejunum and ileum.B12 is Absorbed in terminal ileum along with bile acids, requires intrinsic factor.

Answer 158

B) Reason Type II: Autoimmune hemolytic anemiaPernicious anemiaIdiopathic thrombocytopenic purpuraErythroblastosis fetalisAcute hemolytic transfusion reactions, Rheumatic fever

Answer 159

A) Reason A lumbar puncture is used to inject anesthetic material in the epidural space or to withdraw CSF from the subarachnoid space. • A spinal tap is typically performed at the L4-L5 or above L4 interspace.

Answer 160

A) Reason Free radicals can be eliminated by enzymes (e.g., catalase, superoxide dismutase, transferrin, glutathione peroxidase), spontaneous decay, antioxidants (e.g., vitamins A, C, E).

Answer 161

D) Reason Patient can understand the written words indicating that his visual and the frontal cortex are intact but only problem is the primary auditory cortex lesion

Answer 162

C) Reason Staging of the tumors is the best way to detect the spread and extent of the tumors, one important system is the TNM staginh system.

Answer 163

B) Reason The thyroid gland (from 2nd-6th tracheal rings) consists of right and left lobes connectedby a narrow isthmus from 2nd-4th tracheal rings. It is surrounded by a sheathformed of pretracheal fascia, and this sheath attaches thegland to the larynx and the trachea. I

Answer 164

D) Reason Cerebellum Modulates movement; aids in coordination and balance.Input:Contralateral cortex via middle cerebellar peduncle. Ipsilateral proprioceptive information via inferior cerebellar peduncle from the spinal cord (input nerves = climbing and mossy fibers). Lesion causes ipsilatral ataxia.

Answer 165

A) Reason REM sleep (25%) beta waves: Loss of motor tone, brain O2 use, and variable pulse and blood pressure; when dreaming and penile/clitoral tumescence occur; may serve a memory processing function

Answer 166

A) Reason Rickets is the most appropriate answer.

Answer 167

E) Reason Lesions of the vestibular nuclei and pathways may produce nystagmus, vertigo, nausea, and vomiting. It can be horizontal by up & down tippling or vertical by side by side tippling of head.

Answer 168

E) Reason E.Coli is the causative agent here.

Answer 169

A) Reason Superior Bronchus of the lungs is closely related with the apical segment and it contains superior apical segment that can be involved in carcinoma of superior bronchus.

Answer 170

E) Reason Stomach cancer:Almost always adenocarcinoma. Early aggressive local spread and node/liver metastases. Often presents with acanthosis nigricans. Intestinal—associated with H. pyloriinfection, dietary nitrosamines (smoked foods), tobacco smoking, achlorhydria, chronic gastritis.

Answer 171

D) Reason Risk Factors of CA Urinary bladder are: Associated with problems in your Pee SAC: Phenacetin, Hydrocarbons, Smoking, Aniline dyes, and Cyclophosphamide.

Answer 172

D) Reason A large part of the frontal cortex rostral to the central sulcus is related to the control of movements, reflex action, primarily on the opposite side of the body

Answer 173

B) Reason IE: Mitral valve is most frequently involved. Tricuspid valve endocarditis is associated with IV drug abuse (don’t “tri” drugs). Associated with S. aureus, Pseudomonas, and Candida.Complications: chordae rupture, glomerulonephritis, suppurative pericarditis, emboli. Treated with with IV penicillin.

Answer 174

E) Reason Characteristics include decreased platelet count and prolonged bleeding time; bone marrow aspiration reveals decreased megakaryocytes when caused by decreased platelet production and increased megakaryocytes when caused by increased platelet destruction.

Answer 175

C) Reason Risk factors: inc. estrogen exposure, inc. total number of menstrual cycles, older age at 1st live birth, obesity (inc. estrogen exposure as adipose tissue converts androstenedione to estrone), BRCA1and BRCA2 gene mutations, African American ethnicity (inc. risk for triple breast cancer)

Answer 176

E) Reason NASAL CAVITY: The nasal cavity is divided into right and left halves by thenasal septum. Ala of nose contain a small suspended cartilage, sesamoid cartilage. The septum is made up of the septal cartilage, the vertical plate of the ethmoid, and the vomer.

Answer 177

A) Reason All cell line are decreased RBCs, WBCs and Platelets (Pancytopenia) in a case of Aplastic anemia manifests as anemia, repeated infections and dec. platelets, can be diagnosed by bone marrow biopsy (shows pancytopenia)

Answer 178

C) Reason Corticospinal tract: UMNcell body in 1° motor cortex then descends ipsilaterally (through internal capsule), most fibers decussate at caudal medulla (pyramidal decussation) then descends contralaterally. Associated with skilled motor actions.

Answer 179

C) Reason PR segment is the part of ECG from end of P wave to start of R wave and it represents the atrial depolarization.

Answer 180

E) Reason Measurement of renal plasma flow (RPF)—clearance of para-aminohippuric acid (PAH)■ PAH is filtered and secreted by the renal tubules.■ Clearance of PAH is used to measure RPF.

Answer 181

C) Reason In the hiven scenario, the patient was fisrt having liver abscess that later on directly invaded into the chest causing right lung abscess.

Answer 182

B) Reason associated with H. pyloriinfection, dietary nitrosamines (smoked foods), tobacco smoking, achlorhydria, chronic gastritis. Commonly on lesser curvature; looks like ulcer with raised margins.

Answer 183

E) Reason Relations of Trachea in Superior Mediastinum are Right side: Azygos vein, right vagus nerve, and pleura.• Left side: Arch of the aorta, left common carotid, left subclavian arteries, left vagus nerve, left phrenic nerve, andpleura.

Answer 184

A) Reason Achondroplasia: Is a single gene autosomal dominant trait. Failure of longitudinal bone growth (endochondral ossification) leading to short limbs. Membranous ossification is not affected and cause large head relative to limbs.

Answer 185

E) Reason Leukocyte: Are the nucleated cell developed in marrow.Divided into granulocytes (neutrophil, eosinophil, basophil) and mononuclear cells (monocytes, lymphocytes). Responsible for defense against infections.

Answer 186

A) Reason ANTERIOR MEDIASTINUMThe contents of the anterior mediastinum include thesternopericardial ligaments, lymph nodes, and remains ofthymus.

Answer 187

D) Reason Normal pacemaker of the heart is the SA node, but in case of any ectopic pacemaker especially the AV node, the P wave will be absent but the QRS complexes will be present.

Answer 188

A) Reason Nociceptors: ■ are associated with the detection and perception of noxious stimuli (nociception).■ The receptors for pain are free nerve endings in the skin, muscle, and viscera. They also sense for extreme of temperature (heat and cold)

Answer 189

C) Reason Fibrocartilage has type I collagen in addition to type II, giving it greater resistance to being stretched (tensile strength), and is the type of cartilage found in intervertebral disks of the vertebral column and the menisci of the knee, and may form the attachment of ligaments and tendons to bone

Answer 190

B) Reason Hormone replacement therapy: Used for relief or prevention of menopausal symptoms (e.g., hot flashes, vaginal atrophy) and osteoporosis (decrease estrogen, decrease osteoclast activity).

Answer 191

B) Reason The epithelial lining of the trachea and bronchi is pseudostratified columnar in which all cells lie on the same basal membrane with their nuclei at different levels but only some reach the luminal surface.

Answer 192

B) Reason Na+/K+ATPase (or Na–K+ pump) in cell membranes transports Na+ from intracellular to extracellular fluid and K+ from extracellular to intracellular fluid; it maintains low intracellular [Na+] and high intracellular [K+].

Answer 193

A) Reason Lesions, usually in the dominant hemisphere and which include areas 5 and 7 of the posterior parietal association areas, often result in apraxia (also seen with lesions to the premotor cortex). Apraxia is a disruption of the patterning and execution of learned motor movements

Answer 194

E) Reason DEFICIENCY: Night blindness (nyctalopia); dry, scaly skin (xerosis cutis); alopecia; corneal degeneration (keratomalacia); immune suppression.

Answer 195

D) Reason Erythrocyte: Carries O2 to tissues and CO2 to lungs. Anucleate and biconcave A, with large surface area-to-volume ratio for rapid gas exchange. It is the main contributer of blood viscosity.

Answer 196

A) Reason The temporomandibular joint articulates above with themandibular fossa (glenoid fossa) and the articular tubercle of the temporalbone. It articulates below with the head of the mandible.

Answer 197

D) Reason Alcoholic cirrhosis: Final and irreversible form. Micronodular, irregularly shrunken liver with “hobnail” appearance. Sclerosis around central vein (zone III). Has manifestations CLD, derranged coagulation, raised AST and ALT and sometimes Pnemonia.

Answer 198

B) Reason VEINS:There is a single vein on each side. The right suprarenal veindrains into the inferior vena cava; the left suprarenal veindrains into the left renal vein.

Answer 199

B) Reason Osteoblasts and osteocytes produce the type I collagen in bone, along with other components of bone ECM (osteoid). That is ossified later on.

Answer 200

B) Reason Temporal lobe lesion causes depression and loss of motivation along with auditory impairment. Patients with unilateral damage to the primary auditory cortex show little loss of auditory sensitivity but have some difficulty in localizing sounds in the contralateral sound field.

Answer 201

C) Reason During the chest stab wound, ipsilatral lung is developed into an opened valve pneumothorax leading to ipsilatral lung collapse.

Answer 202

A) Reason FUNCTION: Stimulation of endometrial glandular secretions and spiral artery developmentMaintenance of pregnancydec. myometrial excitability

Answer 203

A) Reason Entamoeba hisrolytica:Amebiasis: bloody diarrhea (dysentery), liver abscess (“anchovy paste” exudate), RUQ pain (histology shows flask-shaped ulcer if submucosal abscess of colon ruptures). Treated with metronidazole and tinidazole.

Answer 204

D) Reason Excitatory pathway—cortical inputs stimulate the striatum, stimulating the release of GABA, which disinhibits the thalamus via the GPi/SNr (inc. motion).Inhibitory pathway—cortical inputs stimulate the striatum, which disinhibits STN via GPe, and STN stimulates GPi/SNr to inhibit the thalamus (dec. motion).

Answer 205

D) Reason In Western society, most common cause of fatty liver is alcohlism and in our society where alcohlism is not common, here cause is obesity.

Answer 206

E) Reason P wave—atrial depolarization. Atrial repolarization is masked by QRS complex.PR interval is the time from atrial depolarization to start of ventriclar depolarization—represents conduction delay through AV node (normally < 200 msec).

Answer 207

E) Reason Intracellular fluid (ICF)■ is two-thirds of TBW.■ The major cations of ICF are K+ and Mg2+

Answer 208

B) Reason Epinephrine: Affects β > α Clinical uses: Anaphylaxis, open angle glaucoma, asthma, hypotension; α effects predominate at high doses.

Answer 209

C) Reason As in case of blast injury, both the eardrum and choclea are affected, so mixed type of hearing loss it is

Answer 210

E) Reason Rock crush is associated with silicosis exposure

Answer 211

C) Reason Patient given in this scenario is having high pH (alkalosis) and dec. CO2 shows it to be respiratory alkalosis. Respiratory alkalosis■ is caused by increased alveolar ventilation and loss of CO2.a. Decreased arterial Pco2, which is the primary disturbance, causes a decrease in [H] and [HCO3] by mass action.

Answer 212

C) Reason Patient given in this scenario is having high pH (alkalosis) and dec. CO2 shows it to be respiratory alkalosis. Respiratory alkalosis■ is caused by increased alveolar ventilation and loss of CO2.a. Decreased arterial Pco2, which is the primary disturbance, causes a decrease in [H] and [HCO3] by mass action.

Answer 213

E) Reason a. Early proximal tubule—special features■ reabsorbs Na+ and H2O with HCO3 glucose, amino acids, phosphate, and lactate.

Answer 214

E) Reason As the patient is having compromised renal functions, and quinolones are relatively safe in CRF than Aminoglycosides and penicillin.

Answer 215

D) Reason FINDINGS: Hypertension, weight gain, moon facies, truncal obesity, buffalo hump, hyperglycemia (insulin resistance), skin changes (thinning, striae), osteoporosis, amenorrhea, and immune suppression.

Answer 216

A) Reason TOXICITY: Addiction, respiratory depression, constipation, miosis (pinpoint pupils), additive CNS depression with other drugs.

Answer 217

B) Reason V/Q approaches 0 = airway obstruction (shunt) and in COPD. In shunt, 100% O2 does not improve Po2.V/Q approaches ∞ = blood flow obstruction (physiologic dead space). Assuming < 100% dead space, 100% O2 improves Po2

Answer 218

C) Reason Broca area Lesion: Nonfluent/Anomic aphasia with intact comprehension.Broca area—inferior frontal gyrus of frontal lobe.

Answer 219

D) Reason • Sulphur containing amino acids: Cysteine,Methionine • Amino acids with amide group: Asparagine, Glutamine

Answer 220

A) Reason The common peroneal nerve descends through thepopliteal fossa. It then passes laterally aroundthe neck of the fibula, pierces the peroneus longus muscle,and divides into the superficial and the deep peroneal nerves.

Answer 221

D) Reason TV-D space x RR = 350-100 x 18 = 250 x 18= 4500ml/min = 4.5L/ min

Answer 222

D) Reason T 10 vertebra is located at the level of umblicus, and its nerve root enters the rectus sheet at its level

Answer 223

B) Reason Actinic keratosis:1. This premalignant epidermal lesion is caused by chronic excessive exposure to sunlight. 2. Characteristics include rough, scaling, poorly demarcated plaques on the face, neck, upper trunk, or extremities

Answer 224

B) Reason Paracortex Houses T cells. Region of cortex between follicles and medulla. Contains high endothelial venules through which T and B cells enter from blood. Not well developed in patients with DiGeorge syndrome.

Answer 225

B) Reason Systemic lupus erythematosus (SLE) 1. SLE, the prototype connective tissue disease, most often affects women (80% of patients), usually those of childbearing age. 2. SLE is marked by the presence of a spectrum of ANAs and by extensive deposits of antigen-antibody complexes mediated inflammatory lesions involving multiple organ systems.

Answer 226

D) Reason Awake (eyes open) Alert, active mental concentration Beta (highest frequency, lowest amplitude)Awake (eyes closed) Alpha waves.

Answer 227

E) Reason Antiphospholipid Antibody Syndrome: This syndrome (previously called the lupus anticoagulant syndrome) is the most common aquired thrombotic disorder, it has protean clinical manifestations, including recurrent thromboses, repeated miscarriages, cardiac valve vegetations, and thrombocytopenia.

Answer 228

D) Reason Identical twins are the genetically same to each other in all the antigenic and cellular proteins, so their no tissue rejection reaction occur in transplant of identical twins.

Answer 229

C) Reason MECHANISM: D2 receptor antagonist. decrease resting tone, contractility, LES tone, motility. Does not influence colon transport time.

Answer 230

E) Reason Thyroglossal duct cyst presents as an anterior midline neck mass that moves with swallowing or protrusion of the tongue (vs. persistent cervical sinus leading to branchial cleft cyst in lateral neck).

Answer 231

B) Reason TOXICITY of Cisplatin and Carboplatin: Nephrotoxicity and acoustic nerve damage. Prevent nephrotoxicity with amifostine (free radical scavenger) and chloride diuresis.

Answer 232

E) Reason Anencephaly: Malformation of anterior neural tube resulting in no forebrain, open calvarium (“frog-like appearance”). Clinical findings: inc. AFP; polyhydramnios (no swallowing center in brain). Associated with maternal diabetes (type I). Maternal folate supplementation dec. risk.

Answer 233

B) Reason MECHANISM: Block thyroid peroxidase, inhibiting the oxidation of iodide and the organification (coupling) of iodine leading to inhibition of thyroid hormone synthesis. Propylthiouracil also blocks 5′-deiodinase, which dec. peripheral conversion of T4 to T3

Answer 234

D) Reason Crosses epithelial cells by transcytosis. Most produced antibody overall, but released into secretions (tears, saliva, mucus) and early breast milk (known as colostrum).

Answer 235

C) Reason PAIN OF APPENDICITISVisceral pain in the appendix is produced by distention of its lumen or spasm of its muscle. The afferentpain fibers enter the spinal cord at the level of thetenth thoracic segment, and a vague referred pain isfelt in the region of the umbilicus (T10). Later, the pain shiftsto where the inflamed appendix irritates the parietalperitoneum, and then the pain is precise, severe, and localized.

Answer 236

A) Reason Disruption of mucosal barrier leads inflammation. Antrum is the most common site of ulceration.Can be caused by stress, NSAIDs (dec. PGE2and hence dec. gastric mucosa protection), alcohol, uremia.

Answer 237

B) Reason Normal splitting: Inspiration, drop in intrathoracic pressure inc. venous return to the RV increased RV stroke volume leading to decreased RV ejection time causing delayed closure of pulmonic valve. decreased pulmonary impedance (increased capacity of the pulmonary circulation) also occurs during inspiration, which contributes to delayed closure of pulmonic valve.

Answer 238

C) Reason Non-REM sleep:Stage N1: (5%) Light sleep Thetawaves.Stage N2: (45%) Deeper sleep; when bruxism occurs Sleep spindles and K complexesStage N3: (25%) Deepest non-REM sleep (slow-wave sleep); when sleepwalking, night terrors, and bedwetting occur.Delta waves: (lowest frequency, highest amplitude)

Answer 239

C) Reason Arterial thrombi a. These thrombi are formed inside the vessels in the areas of active blood flow. b. When mature, they demonstrate alternate dark gray layers of platelets interspersed with lighter layers of fibrin. This layering results in the lines of Zahn.

Answer 240

D) Reason Most commonly caused by systemic hypertension D . Also seen with amyloid angiopathy, vasculitis, and neoplasm. Typically occurs in basal ganglia and internal capsule (Charcot-Bouchard aneurysm of lenticulostriate vessels), but can be lobar. Presents with crossed hemiplegia.

Answer 241

D) Reason Most commonly caused by systemic hypertension D . Also seen with amyloid angiopathy, vasculitis, and neoplasm. Typically occurs in basal ganglia and internal capsule (Charcot-Bouchard aneurysm of lenticulostriate vessels), but can be lobar. Presents with crossed hemiplegia.

Answer 242

E) Reason • Renal fascia: This is a condensation of areolar tissue outside the perirenal fat. It encloses the kidneys and thesuprarenal glands.

Answer 243

B) Reason SOURCE: D3 from sun exposure in skin. D2 ingested from plants. Both converted to 25-OH in liver and to 1,25-(OH)2 (active form) in kidney

Answer 244

C) Reason • The auriculotemporal nerve, which supplies the skin ofthe auricle, the external auditory meatus, the temporomandibular joint, and the scalp. This nerve also conveys postganglionic parasympathetic secretomotor fibers fromthe otic ganglion to the parotid salivary gland .

Answer 245

C) Reason QRS complex—ventricular depolarization (normally < 120 msec).QT interval—mechanical contraction of the ventricles.

Answer 246

C) Reason All the features given in scenario are characteristics of black water fever ( dark colored urine is the clue), while CNS involvement is the point to the Dx of Cerebral Malaria.

Answer 247

D) Reason Blood Supply1. The choriocapillaris of the choroid supplies the pigment epithelium, the layers of rods and conesand the outer nuclear layers.2. Central retinal artery supplies rest of the layers of the retina. It is a branch of the ophthalmicartery and is an end artery

Answer 248

B) Reason Durig the slow ejection phase, Ventricular volume is constant (isovolumetric) because all of the valves are closed.■ The “blip” in the aortic pressure tracing occurs after closure of the aortic valve and increased pressure.

Answer 249

B) Reason FUNCTION of Testosterone: Differentiation of epididymis, vas deferens, seminal vesicles (genitalia, except prostate)Growth spurt: penis, seminal vesicles, sperm, muscle, RBCsDeepening of voice(thickens laryngeal cartilage) Closing of epiphyseal plates (via estrogen converted from testosterone) Libido

Answer 250

B) Reason Fetal componentof Placenta: Cytotrophoblast Inner layer of chorionic villi (the frundosum). Cytotrophoblast makes Cells.Syncytiotrophoblast Outer layer of chorionic villi; secretes hCG (structurally similar to LH; stimulates corpus luteum to secrete progesterone during first trimester).

Answer 251

E) Reason FUNCTION: Converted to tetrahydrofolate (THF), a coenzyme for 1-carbon transfer/methylation reactions.Important for the synthesis of nitrogenous bases in DNA and RNA.Found in leafy green vegetables. Absorbed in jejunum. Folate from green vegetables and foliage.

Answer 252

B) Reason Conjugated or the direct bilurubin is raised in hepatitis in which conjugating system of enzymes is intact while unconjugated or the indirect bilurubin is increased in enzyme defects.

Answer 253

C) Reason • The respiratory area is lined by pseudostratified, ciliated columnar epithelium. Goblet cells are present as well. The olfactory area is in the posterosuperior area and contains bipolar neurons and mitral cells. Olfactory neurons are constantly replenished.

Answer 254

D) Reason C. difficile: Produces 2 toxins. Toxin A, enterotoxin, binds to the brush border of the gut. Toxin B, cytotoxin, causes cytoskeletal disruption via actin depolymerization causing pseudomembranous colitis leading to diarrhea. Often 2° to antibiotic use, especially clindamycin or ampicillin

Answer 255

C) Reason B-type (brain) natriuretic peptide(BNP): Released from ventricular myocytes in response to tension. Similar physiologic action to ANP, with longer half-life. BNP blood test used for diagnosing heart failure (very good negative predictive value). Available in recombinant form (nesiritide) for treatment of heart failure.

Answer 256

A) Reason The blood flow through the renal system circulation (25% of cardiac output) can be subdivided into the hepatic arterial flow (7% of cardiac output) and the mesenteric-portal circulation (18% of cardiac output

Answer 257

A) Reason Ulnar nerve and artery pass over the Flexor Retinaculum, and this bridge and the carpal bones form the carpaltunnel for the passage of the median nerve and the longflexor tendons of the fingers

Answer 258

A) Reason Treatment of CHF: ACE inhibitors, β-blockers (except in acute decompensated HF), angiotensin II receptor blockers, and spironolactone dec. mortality. Thiazide or loop diuretics are used mainly for symptomatic relief. Hydralazine with nitrate therapy improves both symptoms and mortality in select patients.

Answer 259

E) Reason Inner ear size remains same in child and adult.

Answer 260

C) Reason HLA matching is necessary to prevent the transplant rejection reactions. Host antibodies against donor HLA antigens and leukocytes can cause type 2 HSR.

Answer 261

B) Reason Flexor withdrawal reflex■ is polysynaptic.■ results in flexion on the ipsilateral side and extension on the contralateral side.Somatosensory and pain afferent fibers elicit withdrawal of the stimulated body part from the noxious stimulus.

Answer 262

B) Reason • Coronary sinus The coronary sinus is the main vein of the coronary circulation; it lies in the posterior coronary sulcus. It drains to an opening in the right atrium. It develops from the left sinus venosus.

Answer 263

D) Reason Mobitz type II: Dropped beats that are not preceded by a change in the length of the PR interval (as in type I). It is often found as 2:1 block, where there are 2 or more P waves to 1 QRS response. May progress to 3rd-degree block. Often treated with pacemaker.

Answer 264

A) Reason The enzyme is coagulase.Coagulase, by clotting plasma, serves to wall off the infectedsite, thereby retarding the migration of neutrophils into the site. It is positive in virulent strains of Staphylococci.

Answer 265

C) Reason Also use viral load to monitor effect of drug therapy.AIDS diagnosis ≤ 200 CD4+ cells mm3(normal: 500–1500 cells/mm3).HIV-positive with AIDS-defining condition (e.g., Pneumocystis pneumonia) or CD4 percentage < 14%.

Answer 266

E) Reason people fear hospitals because they think they will become handicapped and dependent on the medications.

Answer 267

D) Reason The midbrain comprises two lateral halves called the cerebral peduncles; each of these is divided into an anterior part, the crus cerebri; and a posterior part, the tegmentum, by a pigmented band of gray matter, the substantia nigra.

Answer 268

A) Reason In pulmonary embolism V/Q become infinity.

Answer 269

E) Reason Left circumflex coronary artery (LCX)— a branch of LCA supplies lateral and posterior walls of left ventricle

Answer 270

A) Reason Plantar flexion (toes pointing downward): Gastrocnemius, soleus, plantaris, peroneus longus, peroneus brevis,tibialis posterior, flexor digitorum longus, planteris tendon and flexor hallucis longus muscles.

Answer 271

B) Reason PROLAPSE OF THE UTERUS:The levatores ani muscles and the transverse cervical,pubocervical, uterosacral and sacrocervical ligaments are of verygreat importance in supporting and positioning the uterus. Damage to these structures during childbirthor as a result of general poor body muscular tone mayresult in downward displacement of the uterus, cal led uterine prolapse

Answer 272

A) Reason Trypsinogen: is Converted to trypsin by enterokinase/enteropeptidase, a brush-border enzyme on the duodenal and jejunal mucosa

Answer 273

D) Reason Nutmeg liver Due to backup of blood into liver. Commonly caused by right-sided heart failure and Budd-Chiari syndrome. The liver appears mottled like a nutmeg. If the condition persists, centrilobular congestion and necrosis can result in cardiac cirrhosis.

Answer 274

C) Reason Syringomyelia: Cystic cavity (syrinx) within the spinal cord A(if central canal leading to hydromyelia). Crossing anterior spinal commissural fibers are typically damaged first. Results in a “cape-like,” bilateral loss of pain and temperature sensation in upper extremities (fine touch sensation is preserved).

Answer 275

A) Reason Subclavian veing alongwith internal jugulat vein forms the brachiocephalic trunk.

Answer 276

E) Reason Secretin S cells (duodenum):Functions: Increases pancreatic HCO3 secretion gastric acid secretionbile secretion.

Answer 277

E) Reason Selective IgAdeficiency:Unknown. Most common 1° immunodeficiency.Majority Asymptomatic. Can see Airway and GI infections, Autoimmune disease, Atopy, Anaphylaxis to IgA-containing products.

Answer 278

D) Reason Small Cell CA: Undifferentiated , very aggressive.Paraneoplastic Syndrome: May produce ACTH, ADH, or Antibodies against presynaptic Ca2+ channels (Lambert-Eaton myasthenic syndrome). Amplification of myconcogenes common. Inoperable; treat with chemotherapy

Answer 279

E) Reason Lactation After labor, the dec. in progesterone and estrogen disinhibits lactation. Suckling is required to maintain milk production, since inc. nerve stimulation inc. oxytocin and prolactin.

Answer 280

A) Reason The spinal cord is tapered below to formthe conus medullaris (L1-L2). The filum terminale is aprolongation of the pia mater that extends from the conus tothe back of the coccyx

Answer 281

B) Reason Distribution of frequency is the number of values repetition that a specified quantity appears in the given data. Here the most frequently appeared quantity is known as mode.

Answer 282

D) Reason Functions of Angiotensin-II are: (1) It increases thirst and therefore water intake.(2) It causes vasoconstriction of the arterioles, thereby increasing TPR and arterial pressure.

Answer 283

A) Reason Meissner corpuscle are low frequency receptors, Present in nonhairy skin sense the Velocity and are Rapidly adapting receptors.

Answer 284

A) Reason CA Colon: Screen patients > 50 years old with colonoscopy or stool occult blood test.“Apple core” lesion seen on barium enema x-ray.CEA tumor marker: good for monitoring recurrence, not useful for screening.

Answer 285

C) Reason Platelet (thrombocyte) Involved in 1° hemostasis. Small cytoplasmic fragment derived from megakaryocytes. Life span of 8–10 days. When activated by endothelial injury, aggregates with other platelets and interacts with fibrinogen to form platelet plug and clot retraction.

Answer 286

B) Reason The main part of the larynx is thus elevated to the posterior surface of the epiglottis, and the entrance into the larynx is now closed.

Answer 287

A) Reason Tabes dorsalis Caused by 3° syphilis. Results from degeneration (demyelination) of dorsal columns and roots leading to impaired sensation and proprioception and progressive sensory ataxia (inability to sense or feel the legs causes poor coordination)

Answer 288

A) Reason The bronchi, connective tissue, and visceral pleura are supplied by the bronchial arteries, which are branches of the descending thoracic aorta. Right broncheal artery is the branch of the right posterior intercostal artery.

Answer 289

D) Reason Transudate: Decreased protein content, blood cells as well as low specific gravity. Causes are CHF, nephrotic syndrome, or hepatic cirrhosis.

Answer 290

E) Reason Shivering is the most potent mechanism for increasing heat production. ■ Cold temperatures activate the shivering response, which is orchestrated by the posterior hypothalamus

Answer 291

B) Reason Surgery is one of the stressful conditions, and releases stress hormones via activation the hypothalamus secretion of ACTH.

Answer 292

E) Reason Lipoprotein lipase (LPL)—degradation of TG circulating in chylomicrons and VLDLs. Found on vascular endothelial surface.

Answer 293

A) Reason Tubuloglomerular feedback:, in which increased renal arterial pressure leads to increased delivery of fluid to the macula densa. The macula densa senses the increased load and causes constriction of the nearby afferent arteriole, increasing resistance to maintain constant blood flow.

Answer 294

C) Reason Mycobacterium Tuberculosis is one of the slow growing organism on the culture media, that is the reason that its culture is waited till 6-8 weeks at least.

Answer 295

B) Reason Leiomyoma (fibroid):Most common tumor in females. Often presents with multiple discrete tumors with decreased glandular tissue and increased stroma by glandular dystrophy. Increased incidence in blacks. Benign smooth muscle tumor; malignant transformation is rare.

Answer 296

C) Reason The whole nerve trunk is ensheathed by epineurium, each fasciculus by perineurium, and each nerve fibre by a delicate endoneurium. The toughness of a nerve is due to its fibrous sheaths, otherwise the nerve tissue itself is very delicate and friable

Answer 297

B) Reason In old age, drug elimination system of body (liver as well as kidneys) become senile and their clearing capacity become less than in adulthood. That"s why therapeutic dose can cause toxicity.

Answer 298

E) Reason Innate defenses can be classified into three major categories: (1)physical barriers, such as intact skin and mucous membranes; (2) phagocytic cells,such as neutrophils, macrophages, and natural killer cells; and (3) proteins, such ascomplement, lysozyme, and interferon

Answer 299

D) Reason ■ In the lungs, hypoxia causes vasoconstriction.■ This response is the opposite of that in other organs, where hypoxia causes vasodilation by opening hyoxia induced K chanel.■ Physiologically, this effect is important because local vasoconstriction redirects blood away from poorly ventilated, hypoxic regions of the lung and toward well-ventilated regions.

Answer 300

D) Reason Local metabolic control■ Blood flow in skeletal muscle exhibits autoregulation and active and reactive hyperemia.■ Demand for O2 in skeletal muscle varies with metabolic activity level, and blood flow is regulated to meet demand.■ During exercise, when demand is high, these local metabolic mechanisms are dominant.■ The local vasodilator substances are lactate, adenosine, and K+.

Answer 301

D) Reason β2 Activation: Vasodilation, bronchodilation, inc. heart rate, inc. contractility, inc. lipolysis, inc. insulin release, dec. uterine tone (tocolysis), ciliary muscle relaxation, inc. queous humor production

Answer 302

A) Reason Widespread activation of clotting leads to a deficiency in clotting factors, which creates a bleeding state.Causes: Sepsis (gram-negative), Trauma, Obstetric complications, acute Pancreatitis, Malignancy, Nephrotic syndrome,

Answer 303

B) Reason Hyperpolarization makes the membrane potential more negative (the cell interior becomes more negative).

Answer 304

C) Reason Erythropoietin Released by interstitial cells in the peritubular capillary bed in response to hypoxia. It is induces the production of RBCs.

Answer 305

B) Reason Delayed complications are Dressler syndrome, HF, arrhythmias, true ventricular aneurysm (outward bulge during contraction, “dyskinesia”).

Answer 306

D) Reason - The telencephalon forms the cerebral hemispheres - The diencephalon forms 4 thalamic derivatives - The mesencephalon forms the midbrain - The metencephalon forms the pons and cerebellum that are closely related to wach other.- The myelencephalon forms the medulla

Answer 307

D) Reason IL-6: An endogenous pyrogen. Also secreted by Th2cells. Causes fever and stimulates production of acute-phase proteins.IL-8: Major chemotactic factor for neutrophils.

Answer 308

B) Reason True hermaphroditism (46,XX or 47,XXY):Also called ovotesticular disorder of sex development. Both ovary and testicular tissue present (ovotestis); ambiguous genitalia. Very rare.

Answer 309

E) Reason Right-dominant circulation = 85% = PDA arises from RCA.Left-dominant circulation = 8% = PDA arises from LCX.Codominant circulation = 7% = PDA arises from both LCX and RCA.

Answer 310

C) Reason Towards the end of the cell division, the telephase, chromatids reach to the corresponding opposite poles in form of double chromatids around which new membrane formed to give daughter cell nuclei.

Answer 311

D) Reason Characterized by:Decreased Ceruloplasmin, Cirrhosis, Corneal deposits (Kayser-Fleischer rings). Copper accumulation, Carcinoma (hepatocellular)Hemolytic anemiaBasal ganglia degeneration (parkinsonian symptoms).

Answer 312

B) Reason The renal vein emerges from the hilum of the kidney in front of the aorta and drains into theinferior vena cava.

Answer 313

C) Reason Ventricular free wall rupture laeding to cardiac tamponade; papillary muscle rupture causes severe mitral Regurgitation; that is a one of the important indication of mitral valve replacement.

Answer 314

C) Reason TOXICITY Reflex tachycardia (treat with β-blockers), hypotension, flushing, headache, “Monday disease” in industrial exposure: development of tolerance for the vasodilating action during the work week and loss of tolerance over the weekend results in tachycardia, dizziness, and headache upon reexposure.

Answer 315

D) Reason Heat exhaustion is caused by excessive sweating. As a result, blood volume and arterial blood pressure decrease laeding to cold clamy extrimities and syncope (fainting) occurs.

Answer 316

E) Reason Reactions in Mitochondria: Fatty acid oxidation (β-oxidation), acetylCoA production, TCA cycle, oxidative phosphorylation.

Answer 317

E) Reason Reactions in Mitochondria: Fatty acid oxidation (β-oxidation), acetylCoA production, TCA cycle, oxidative phosphorylation.

Answer 318

A) Reason Gastrosplenic Ligament: It connects Greater curvature and spleen. It contains Short gastrics, left gastroepiploic vesselsIt separates greater and lesser sacs on the left side.

Answer 319

C) Reason Hypovolumia (blood loss aftr hemmorhage) causes hypoglycemic shock (low BP and high pulse rate). Fluid resuscitation causes heart rate to decrease to normal and than increase BP towards normal value.

Answer 320

E) Reason Anterior pituitary (adenohypophysis):Secretes FSH, LH, ACTH, TSH, prolactin, GH, melanotropin (MSH). Derived from oral ectoderm (Rathke pouch).

Answer 321

E) Reason Hormones act by inhibiting the growth factors and dec. cancer growth. Tamoxifen is the typical example, Tamoxifenmoxifen, a selective estrogen receptor modulator (see Chapter 40), blocks the binding ofestrogen to receptors of estrogen-sensitive cancer cells in breast tissue.

Answer 322

E) Reason • The costal groove is located along the inferior border of each rib (upper aspect of the intercostal space) and provides protection for the intercostal nerve, artery, and vein which are located in the groove. The vein is most superior and the nerve is inferior in the groove (VAN).

Answer 323

B) Reason Release of sympathetic neurotransmitter norepinephrine from a sympathetic nerve ending is modulated by norepinephrine itself, acting on presynaptic α2-autoreceptors, angiotensin II, and other substances.

Answer 324

B) Reason Type IV: Multiple sclerosisGuillain-Barré syndromeGraft-versus-host diseasePPD (test for M. tuberculosis)and BCG.Contact dermatitis (e.g., poison ivy, nickel allergy).

Answer 325

D) Reason Here the markers of HBV given in this scenario show that no recent infection (absent IgM) and furthermore presence of antibodies indicates a previous infection.

Answer 326

D) Reason Proteins:1. Integral proteins■ are anchored to, and imbedded in, the cell membrane through hydrophobic interactions.■ may span the cell membrane.■ include ion channels, transport proteins, receptors, and guanosine 5′-triphosphate (GTP)–binding proteins (G proteins).

Answer 327

C) Reason Veins have more distensibility and calibre than that of arteries and accumulate more blood than that of arteries. Hence blood loss is mainly from veins.

Answer 328

E) Reason Cholecystokinin (CCK): secreted from I cells (duodenum, jejunum)Increases pancreatic secretionIncreases gallbladder contractionDecreases gastric emptyingIncreases sphincter of Oddi relaxation

Answer 329

E) Reason TOXICITY Iatrogenic Cushing syndrome—buffalo hump, moon facies, truncal obesity, muscle wasting, thin skin, easy bruisability, osteoporosis (treat with bisphosphonates), adrenocortical atrophy, peptic ulcers, diabetes (if chronic).Adrenal insufficiency (dec. ACTHg when drug stopped abruptly after chronic use.

Answer 330

B) Reason Causes of Edema by Increased capillary hydrostatic pressure: Arteriolar dilationVenous constrictionIncreased venous pressureHeart failureExtracellular volume expansionStanding (edema in the dependent limbs)

Answer 331

E) Reason The lateral borders of adjacent cells are extensively interdigitated. These characteristics are typical of cells involved in active transport. The lumen of the PCT is frequently clouded by microvilli which do not preserve well during the histologic preparation process.

Answer 332

C) Reason Osteoclasts are derived from cells of blood monocyte lineage, which ultimately come from hematopoietic stem cells. They have variable life span depending body Ca and PO4 levels.

Answer 333

D) Reason Absolute refractory period■ is the period during which another action potential cannot be elicited, no matter how large the stimulus, eg: 0.3 sec in cardiac cycle.■ coincides with almost the entire duration of the action potential.

Answer 334

A) Reason Sinoatrial (SA) node ■ is normally the pacemaker of the heart due to its fast rate and automaticity■ has an unstable resting potential.■ exhibits phase 4 depolarization, or automaticity

Answer 335

B) Reason Among the higher mental functions of the cortex, the cerebrum, lesion manifestations are agraphesthesia (inability to recognize the shape of objects) and prosopagnosia is inability to recognize the face.

Answer 336

E) Reason Diabetes insipidus Characterized by intense thirst and polyuria with inability to concentrate urine (decreased urine Osmolarity) due to lack of ADH. Has a central or nephrogenic cause.

Answer 337

B) Reason Findings: mitochondrial abnormalities, extensive hepatic necrosis, fatty liver (microvascular fatty change), hypoglycemia, vomiting, hepatomegaly, coma.

Answer 338

C) Reason Great splanchnic nerve supply to the abdomenal viscera. Foregut and midgut (thoracic splanchnic nerves: T5-T12) and to the hindgut and pelvic viscera (lumbar splanchnic nerves: L1-L2) synapse in collateral ganglia.

Answer 339

B) Reason Caudal medulla—origin of hypoglossal nerve.Lesion causes Ipsilatral hypoglossal dysfunction (tongue deviates ipsilaterally

Answer 340

D) Reason Ulnar (C8-T1) Fracture of medial epicondyle of humerus “funny bone”.“Ulnar claw” on digit extension and loss of sensation of 3rd and 4th fingers.

Answer 341

C) Reason layers to be penetrted are skin, subcutaneous tissue, fat, muscle layers (2 layers), pleural ligament, pleural layers (2 layers) to lungs.

Answer 342

A) Reason Adaptation to high altitude (Table 4.9) Alveolar Po2 is decreased at high altitude because the barometric pressure is decreased. As a result, arterial Po2 is also decreased (hypoxemia).

Answer 343

B) Reason Autosomal recessive Traits:Albinism, ARPKD (formerly known as infantile polycystic kidney disease), cystic fibrosis, glycogen storage diseases, ABO blood group antigen, hemochromatosis, Kartagener syndrome.

Answer 344

A) Reason Pregnancy is an hypercoagulative state due to loss of antithrombin 3. Acquired deficiency of the Anti-thrombin III is related to the loss of factor in urine.

Answer 345

E) Reason CEA: CarcinoEmbryonic Antigen. Very nonspecific but produced by ∼ 70% of colorectal and pancreatic cancers; also produced by gastric, breast, and medullary thyroid carcinomas.

Answer 346

D) Reason An increased in all factors (including H+) causes a shift of the curve to the right.A decreased in all factors (including H+) causes a shift of the curve to the left.

Answer 347

C) Reason Parasympathetic system is the system of rest and digest. Its activation causes increased GI motility, relaxed GI sphincters and increased GI secretions.

Answer 348

A) Reason Plasmid Contains a variety of genes for antibiotic resistance, enzymes, toxins. It was used in recombinant technology for the first time in history.

Answer 349

C) Reason Heavy weight lifting is most of the time associated with damage to the Lumbosacral spine and its roots. Loss of ankle jerk (root value S1) mean lesion at S1 level.

Answer 350

D) Reason The acinar cells of the exocrine pancreas make up most of its weight.Secretion (serous) are secreted by the pancreatic acini.a. Acinar cells■ produce a small volume of initial pancreatic secretion, which is mainly Na+ and Cl

Answer 351

E) Reason sympathetic stimulation causes increased in heart rate and hence cardiac cycle is decreased and sympathetic activity causes increased firing of nodal fibers and shortens the AV nodal delay.

Answer 352

D) Reason In hemmorhage, plasma volume decreases laeding to decreased arterial pressure and hence decreased GFR and low urine output.

Answer 353

E) Reason ALT and AST are the enzymes of the liver cells. In inflamation of the liver cells membrane is damaged leading to release of these enzymes. Hence their level increased in serum.

Answer 354

A) Reason ■ Examples are Na+-glucose cotransport in the small intestine (jejunum) and renal early proximal tubule and Na+K/2Cl cotransport in the renal thick ascending limb.

Answer 355

E) Reason Campylobacter infection can result in reactive arthritis, primarily in patients with HLA-B27. Other extraintestinal complications, including erythema nodosum and GuillainBarré syndrome, a flaccid paralysis caused by immunologically mediated inflammation of peripheral nerves, are not HLA-linked.

Answer 356

D) Reason • Posterolateral relation of the parotid gland are: The carotid sheath and its contents

Answer 357

D) Reason Sphenoid Complex bone composed of a central body, and greater and lesser wings. Its greater wing forms the floor of the middle cranial fossa.

Answer 358

E) Reason AB positive blood group is an universal accepter, moreover all groups given here all are compatible with AB positive blood group.

Answer 359

E) Reason Vasopressin [antidiuretic hormone (ADH)], IP3 and DAG■ is involved in the regulation of blood pressure in response to hemorrhage, but not in minute-to-minute regulation of normal blood pressure.■ Atrial receptors respond to a decrease in blood volume (or blood pressure) and cause the release of vasopressin from the posterior pituitary.■ Vasopressin has two effects that tend to increase blood pressure toward normal.

Answer 360

E) Reason internal capsule lesion: Contralateral hemiparesis/Crossed hemiplegia (contralatral mouth deviation)Common location of lacunar infarcts, 2° to unmanaged hypertension.

Answer 361

C) Reason Solitarius Visceral Sensory information (e.g., taste, baroreceptors, gut distention). Sensations are Transmitted through thalamus to the cortex.

Answer 362

C) Reason orticosteroids cause neutrophilia, but eosinopenia and lymphopenia. Corticosteroids decrease the formation of prostagladins and decrease the activation of neutrophil adhesion molecules, impairing migration out of the vasculature to sites of inflammation.

Answer 363

B) Reason During the action potential of the neurons, it follows the all or none principle. All the fibers are excited or no one is excited during the action potential.

Answer 364

B) Reason CLINICAL USE of Lidocain : Acute ventricular arrhythmias (especially postMI), digitalis-induced arrhythmias especially post-MI.

Answer 365

A) Reason Treatment: aminoglycoside plus extended spectrum penicillin (e.g., piperacillin, ticarcillin, cefepime, imipenem, meropenem) and quinolones (UTI and pylonephritis).

Answer 366

B) Reason The anterior cruciate ligament is attached below tothe anterior intercondylar area of the tibia, most commonly injured in excessive anterior movementa of the knee joint.

Answer 367

D) Reason Barrett esophagus Glandular metaplasia—replacement of nonkeratinized (stratified) squamous epithelium with intestinal epithelium (nonciliated columnar with goblets cells) in the distal esophagus at squamocolumnar junction. Due to chronic acid reflux (GERD).

Answer 368

D) Reason Schwarm cells are glial cells that make myelin for PNS axons. Unlike oligodendrocytes, which make C S myelin, individual Schwann cells myelinate only a small part of a single axon.

Answer 369

C) Reason Abduction of arm is the combined function if the Supraspinatus muscle and deltoid, supplied by supraspinatus and axillary nerve respectively.

Answer 370

B) Reason Level of serum calcium and serum Phosphate are regulated by renal function. Ca is decreased and phosphate is increased in impaired renal functions.

Answer 371

A) Reason The phrenic nerve (C3–5).Action• Muscle of inspiration: On contraction, the diaphragmpulls its central tendon down and increases the vertical diameter of the thorax

Answer 372

A) Reason Vibrio cholerae Produces profuse rice-water diarrhea via enterotoxin that permanently activates Gs, inc. cAMP. Comma shaped, oxidase positive, grows in alkaline media. Endemic to developing countries. Prompt oral rehydration is necessary

Answer 373

A) Reason Diaphragm is innervated by C3, 4, and 5 (phrenic nerve). Lesion of the nerve leads to respiratory distress and loss of respiratory reflex.

Answer 374

C) Reason TOXICITY Hypokalemic metabolic alkalosis, Thrombocytopenia, hyponatremia, hyperGlycemia, hyperLipidemia, hyperUricemia, and hyperCalcemia. Sulfa allergy

Answer 375

B) Reason Type III:Polyarteritis nodosaPoststreptococcal glomerulonephritisSerum sickness, SLEArthus reaction (e.g., swelling and inflammation following tetanus vaccine)

Answer 376

C) Reason Pacemaker action:Occurs in the SA and AV nodes. Key differences from the ventricular action potential. Normally in SA node. When in AV node, there is no P wave, rest is normal.

Answer 377

C) Reason In golgi apparatus, Glyceraldehyde-3-phosphate to glycerol-3-phosphate (combines with fatty acids to make triglycerides

Answer 378

B) Reason Metaplasia mean transformation of the one type of cells into another type of cells. Here in this scenario, injury caused soft tissue to develop bony (metaplstic) tissue.

Answer 379

E) Reason v wave—inc. right atrial pressure due to filling against closed tricuspid valve. It is absent in mitral stenosis.

Answer 380

E) Reason Osteoblasts are specialized to synthesize and secrete the components of osteoid, type I collagen, and GA Gs. The unique structure of the osteoid, in particular the ordering of the collagen, promotes the formation of a crystalline structure.

Answer 381

B) Reason The posterior triangle is bounded posteriorly by the trapezius muscle, anteriorly by the sternocleidomastoid muscle,and inferiorly by the clavicle

Answer 382

E) Reason Most common causes of anovulationPregnancy, polycystic ovarian syndrome, obesity, HPO axis abnormalities, premature ovarian failure, Anovulatory cycles, hyperprolactinemia, thyroid disorders, eating disorders, female athletes, Cushing syndrome, adrenal insufficiency.

Answer 383

C) Reason Fibrinogen: It is Coagulation factor; converts to fibrin by FibrinopeptidaseA, promotes endothelial repair; correlates with ESR

Answer 384

E) Reason Lymphoma Discrete tumor masses arising from lymph nodes. Presentations often blur definitions. Diagnosed witn immunohistochemistry.

Answer 385

E) Reason Wrist joint is an example of Ellipsoid type. Reference B.D.

Answer 386

E) Reason Normal urine output is about 1ml/kg per hour. So, in a person of 70kg it would be, Urine output= 1ml x 70 x 24 = 1680ml, app = 1.5L.

Answer 387

D) Reason Pneumocystis jirovecii:Causes Pneumocystis pneumonia (PCP), a diffuse interstitial pneumonia. Yeast (originally classified as protozoan). Inhaled. Most infections are asymptomatic. Immunosuppression (e.g., AIDS) predisposes to disease. Diffuse, bilateral CXR appearance. Diagnosed by lung biopsy or lavage. Disc-shaped yeast forms on methenamine silver stain of lung tissue .

Answer 388

E) Reason Primordial germ cells arise from the lining cells in the wall of the yolk sac. At week 4, primordial germ cells migrate into the indifferent gonad.

Answer 389

B) Reason Shivering is the most potent mechanism for increasing heat production. ■ Cold temperatures activate the shivering response, which is orchestrated by the posterior hypothalamus.

Answer 390

E) Reason It causes decreased osmolarity.

Answer 391

E) Reason Rubrospinal tract■ originates in the red nucleus and projects to interneurons in the lateral spinal cord.■ Stimulation of the red nucleus produces stimulation of flexors and inhibition of extensors.

Answer 392

D) Reason Collegenase is protein enzyme that functions to remodeling if the repaired tissues. Its defects leads to abnormal shape of the repaired tissues like abnormal scars.

Answer 393

C) Reason The anterior triangle is bounded above by the body of themandible, posteriorly by the sternocleidomastoid muscle,and anteriorly by the midline

Answer 394

A) Reason In the 3rd week the yolk sac forms the allantois, which extends into the urogenital sinus. Later on, urogenital sinus forms the epithelium of the Urinary bladder.

Answer 395

D) Reason These are the well perfused organs. 25% of the cardiac output goes to the liver; 4-5% (225 ml/min) to the heart; 15% to the brain; 20% to the kidneys; and 100% to the lungs.

Answer 396

A) Reason Conduction Aphasia There is a large fiber bundle connecting areas 22, 39, and 40 with Broca area in the frontal lobe, known as the superior longitudinal fasciculus (or the arcuate fasciculus). A lesion affecting this fiber bundle results in a conduction aphasia.

Answer 397

A) Reason Bitemporal hemianopia (pituitary lesion, chiasm) Left homonymous hemianopia(lesion of ipsilatral optic tract). Left upper quadrantic anopia (right temporal lesion, MCA)

Answer 398

E) Reason Lactose intolerance results from the absence of brush border lactase and, thus, the inability to hydrolyze lactose to glucose and galactose for absorption. Nonabsorbed lactose and H2O remain in the lumen of the GI tract and cause osmotic diarrhea.

Answer 399

C) Reason Color blindness are named as Protonopia as red blindness, Deutronopia as green blindness and tritononopia is blue color blindness.

Answer 400

B) Reason Diagnosis: fasting sugar greater than 110mg/dl, random level greater than 126mg/dl or post glucose greater than 200mg/dl are diagnostic ojf diabetes mellitus.

Answer 401

D) Reason dermatome is same as of shoulder tip.

Answer 402

B) Reason Signal-relaying cells with dendrites (receive input), cell bodies, and axons (send output). Cell bodies and dendrites can be stained via the Nissl substance (stains RER).

Answer 403

B) Reason Can also lead to biliary colic—neurohormonal activation (e.g., by CCK after a fatty meal) triggers contraction of the gallbladder, forcing a stone into the cystic duct. May present with bloating and with or without pain (e.g., in diabetics).

Answer 404

E) Reason In hypovolumic shock, Blood volume decreases that causes decreased BP and increased heart rate. As the fluid therapy is started, heart rate slow down to normal and then BP also goes up to normal.

Answer 405

A) Reason HSV-1: Gingivostomatitis, keratoconjunctivitis, temporal lobe encephalitis (most common cause of sporadic encephalitis in the United States), herpes labialis. Latent in trigeminal ganglia.Transmitted by respiratory secretions, saliva.

Answer 406

B) Reason TOXICITY Gastric ulceration, tinnitus (CN VIII). Chronic use can lead to acute renal failure, interstitial nephritis (contraindicated in CRF), and upper GI bleeding. Risk of Reye syndrome in children treated with aspirin for viral infection.

Answer 407

B) Reason In thrombus formation, platelets adhesion takes place over the injured endothelium making platelet plug that is site for thrombus formation.

Answer 408

E) Reason Functional tumor (microprolactinoma) presentation is based on the hormone produced (e.g., prolactinoma: amenorrhea, galactorrhea, low libido, infertility; somatotropic adenoma: acromegaly).

Answer 409

A) Reason Sympathetic system stimulation or secretion of any stress hormone causes increased contratility of the heart . Ach. is a parasympathetic hormone.

Answer 410

B) Reason It is easy to assess and manage the nuitrional deficiencies in the in diet rather to do it with clinical or the pharmacological interventions that would be expensive and complicated as well.

Answer 411

E) Reason Type II: Autoimmune hemolytic anemiaPernicious anemiaIdiopathic thrombocytopenic purpuraErythroblastosis fetalisAcute hemolytic transfusion reactionsRheumatic feverGoodpasture syndromeBullous pemphigoidPemphigus vulgaris.

Answer 412

B) Reason Staging of tumor: Degree of localization/spread based on site and size of 1° lesion, spread to regional lymph nodes, presence of metastases. Based on clinical (c) or pathology (p) findings. Example: cT3N1M0

Answer 413

A) Reason FUNCTION of Glucagon are: Catabolic effects of glucagon:Increases Glycogenolysis, gluconeogenesis(in liver)Inc. Lipolysis and ketone production

Answer 414

E) Reason If gluteus minimus then the pelviswill sink downward on the opposite, unsupportedside. The patient is then said to exhibit a positiveTrendelenburg’s sign.

Answer 415

D) Reason Preload: Preload approximated by ventricular EDV; depends on venous tone and circulating blood volume.

Answer 416

A) Reason Heavy weight lifting is most of the time associated with damage to the spinal nerve roots. Here ankle jerk (root value of S1) loss mean lesion is at S1 level.

Answer 417

D) Reason Total peripheral resistance: maintained by vasomotor tone.Changes in TPR leads to altered CO at a given RA pressure; however, mean systemic pressure (x-intercept) is unchanged.

Answer 418

B) Reason The internal jugular vein is a large vein that drains bloodfrom the brain, face, scalp, and neck . It starts as acontinuation of the sigmoid venous sinus and leaves theskull through the jugular foramen and ends at the medial border of clavicle by forming bracheocephalic vein.

Answer 419

C) Reason Fibrocartilage has type I collagen in addition to type II, giving it greater resistance to being stretched (tensile strength), and is the type of cartilage found in intervertebral disks of the vertebral column and the menisci of the knee.

Answer 420

B) Reason Most common cause of unconjugated /indirect hyperbilirubinemia are: Hemolytic, physiologic (newborns), Crigler-Najjar, Gilbert syndrome

Answer 421

C) Reason Coagulase is an enzyme that causes plasma to clot byactivating prothrombin to form thrombin. It is the main virulent factor of staph. aureus. Thrombin then catalyzes the activation offibrinogen to form the fibrin clot.

Answer 422

A) Reason All the fluids given in the list are either hypotonic to the body (0.1, 0.2 percent NaCl) or Isotonic such as (0.9 percent NaCl or 5 percent dextrose) except 10 percent Dextrous that is Hypertonic.

Answer 423

A) Reason E. coli is the leading cause of community-acquired urinary tract infections.These infections occur primarily in women; causing frequent burning Micturation and suprapubic tenderness.

Answer 424

B) Reason Compliance—change in lung volume for a given change in pressure; maintained by surfactant decreased in pulmonary fibrosis, pneumonia, and pulmonary edema and increased surfactant; increased in emphysema, low or none surfactantand normal aging

Answer 425

A) Reason They synthesize adenosine triphosphate (ATP ), contain their own double-stranded circular DNA, and make some of their own proteins and replicate themselves by virtue of their own genetic material.

Answer 426

B) Reason T wave—ventricular repolarization. T-wave inversion may indicate recent MI. While short T wave in hypokalemia and tall T wave in hyperkalemia.

Answer 427

B) Reason LIGAMENTSbetween 2 Vertebra:• Supraspinous ligament: Connects adjacent spines.• Interspinous ligament: Connects adjacent spines.• Ligamentum flavum: Connects adjacent laminae

Answer 428

E) Reason FUNCTION Stimulates linear growth and muscle mass through IGF-1/somatomedin secretion. Increases lipolysis and insulin resistance (diabetogenic).

Answer 429

D) Reason Trypsinogen: Converted to active enzyme trypsin by enterokinaseto activation of other proenzymes and cleaving of additional trypsinogen molecules into active trypsin (positive feedback loop)

Answer 430

E) Reason Gilbert syndrome: Mildly dec. UDP-glucuronosyltransferase conjugation activity dec. bilirubin uptake by hepatocytes. Asymptomatic or mild off and on jaundice. Elevated unconjugated bilirubin without overt hemolysis.

Answer 431

E) Reason Speed of conduction—Purkinje > atria > ventricles > AV node.Pacemakers—SA > AV > bundle of His/Purkinje/ventricles.

Answer 432

E) Reason Epiphysial arteries • These are derived from periarticular vascular arcades (circulus vasculosus) found on the nonarticular bony surface. These supply the metaohysis and epiohysis.

Answer 433

C) Reason Ingestion of larvae encysted in undercooked pork.Ingestion of eggs. Treated with Albendazole or ivermectin.

Answer 434

A) Reason Plasma is part of blood minus blood cells while serum is the part of plasma minus clotting factors.

Answer 435

A) Reason Rapidly adapting, or phasic, receptors (pacinian corpuscle; light touch)■ show a decline in action potential frequency with time in response to a constant stimulus.■ primarily detect onset and offset of a stimulus

Answer 436

E) Reason Renal fascia: This is a condensation of areolar tissue outside the perirenal fat. It encloses the kidneys and thesuprarenal glands

Answer 437

A) Reason Peyer patches: Unencapsulated lymphoid tissue found in lamina propria and submucosa of ileum. Contain specialized M cells that sample and present antigens to immune cells

Answer 438

D) Reason Aminotransferases (AST and ALT) (often called “liver enzymes”)Viral hepatitis (ALT > AST), viral hepatitis is more common than alcoholic one.Alcoholic hepatitis (AST > ALT)

Answer 439

E) Reason Endomysium surrounds each muscle fibre separately. Perimysium surrounds bundles (fasciculi or myonemes) of muscle fibres of various sizes. Epimysium surrounds the entire muscle.

Answer 440

E) Reason Febrile nonhemolytic transfusion reaction:Type II hypersensitivity reaction. Host antibodies against donor HLA antigens and leukocytes. through MHC.

Answer 441

D) Reason This is particularly important in relation to thespinothalamic and spinoreticular pathways and the perception of pain.Presynaptic inhibition influences many, possibly all, primary afferent terminals. Amuch-investigated site ofpresynaptic effects is the substantia gelatinosa.

Answer 442

E) Reason Positive chronotropic effect■ increases heart rate by increasing the rate of phase 4 depolarization.■ More action potentials occur per unit time because the threshold potential is reached more quickly and, therefore, more frequently.

Answer 443

C) Reason Interstitial fluid is three-fourths of the ECF. Thus, it is one-fourth of TBW (3/4 × 1/3).■ The composition of interstitial fluid is the same as that of plasma except that it has little protein. Thus, interstitial fluid is an ultrafiltrate of plasma.

Answer 444

A) Reason Thrombolytics Directly or indirectly conversion of plasminogen (a natural Thrombolytic) to plasmin, which cleaves thrombin and fibrin clots. inc. PT, inc. PTT, no change in platelet count.

Answer 445

A) Reason Some fibers from the nasocilliary branch go and synapse in the ciliary ganglionand reach the eyeball in the short ciliary nerves.

Answer 446

D) Reason A better communication skill is one of the important step of the relationship between a Doctor and a patient, it can be best developed by active listening and respect the views and ideas of the patients at their level.

Answer 447

C) Reason Normal contribution of the major nutrients in diet are as: Carbohydrates 45-65 percent, proteins 25-40 percent and fats 15-20 percent.

Answer 448

C) Reason Here in this scenario, all the features given are in favour of malarial diagnosis. While decreased Hb is the feature of hemolysis by the RBC burst and leading to spleenomegaly.

Answer 449

A) Reason Epiphysis The ends and tips of a bone which ossify from secondary centres are called epiphyses.

Answer 450

D) Reason TOXICITY: Highly lipid soluble and stored in body fat; thus, very slow to be removed from body.Extrapyramidal system side effects (e.g., dystonia and dyskinesias). Treatment: benztropine or diphenhydramine.

Answer 451

C) Reason UPPER TRUNK LESIONS OF THE BRACHIALPLEXUS (ERB-DUCHENNE PALSY)Upper trunk (C5-6) lesions of the brachial plexus result fromdisplacement of the head to the opposite side and depression of the shoulder on the same side, as during fallson the shoulder or in infants during a difficult delivery

Answer 452

E) Reason Hashimoto thyroiditis: Most common cause of hypothyroidism in iodine-sufficient regions; an autoimmune disorder (anti-thyroid peroxidase, antithyroglobulin antibodies).

Answer 453

A) Reason Plasmodium Malarie is a specie of the Malaria causing parasites. P.Malarie fever spikes are there after every 3 days (Qurtran malaria).

Answer 454

D) Reason TOXICITY Hypokalemic metabolic alkalosis, hyponatremia, hyperGlycemia, hyperLipidemia, hyperUricemia, and hyperCalcemia. Sulfa allergy.

Answer 455

E) Reason Calcitonin■ is synthesized and secreted by the parafollicular cells of the thyroid.■ secretion is stimulated by an increase in serum [Ca2+].■ acts primarily to inhibit bone resorption.■ can be used to treat hypercalcemia and hyperparathyroidism.

Answer 456

D) Reason Central retinal artery supplies rest of the layers of the retina. It is a branch of the ophthalmicartery and is an end artery. It enters the optic nerve on its lower surface 15-20 mm behind theglobe. The normal artery : vein ratio is 2 : 3

Answer 457

D) Reason Clinical features 1. Bone pain- due to microfractures 2. Increasing hat size- Skull is commonly affected. 3. Hearing loss-impingement on cranial nerve 4. Lion-like facies- involvement of craniofacial bones 5. Isolated elevated alkaline phosphatase-most common cause of isolated elevated alkaline phosphatase in patients> 40 years old

Answer 458

D) Reason Type II: Autoimmune hemolytic anemiaPernicious anemiaIdiopathic thrombocytopenic purpuraErythroblastosis fetalisAcute hemolytic transfusion reactionsRheumatic feverGoodpasture syndromeBullous pemphigoidPemphigus vulgaris

Answer 459

D) Reason As NSAIDs are contraindicated in chronic renal failure and for the best control in DM and its complication (as CRF) is the Ketorolac.

Answer 460

C) Reason When the thumb is fully extended, a depression known as the anatomical snuffbox is seen on the lateralaspect of the wrist, immediately distal to the radial styloid process. Radial nerve is susceptible to injury here in this box.

Answer 461

A) Reason Stress hormones are the hormones that cope with the stressful conditions. these include GH, Epinephrine, Norepinephrine, Cortisol and glucagon.

Answer 462

D) Reason Lymph Drainage:The Cervical cancer drains into the internal and theexternal iliac nodes.

Answer 463

B) Reason Phase 2 = plateau—Ca2+ influx through voltage-gated Ca2+ channels balances K+ efflux. Ca2+ influx triggers Ca2+ release from sarcoplasmic reticulum and myocyte contraction.

Answer 464

B) Reason All the features given in scenario are characteristics of malaria while H/O collapse indicates its CNS association that is cerebral Malaria.

Answer 465

C) Reason Nerve SupplyParasympathetic secretomotor supply is from the facialnerve via the chorda tympani. Marginal mandibular branch is closely related to gland and is frequently injured in its surgery.

Answer 466

C) Reason drenal cortex and medulla: Adrenal cortex (derived from mesoderm) and medulla (derived from neural crest).

Answer 467

B) Reason Venous thrombosis arises most often in the deep veins of the lower extremities with extremely painful swollen limb. It is often associated with inflammation and is then termed thrombophlebitis.

Answer 468

B) Reason Most common presentation is abdominal distension and a firm, irregular mass that can cross the midline (vs. Wilms tumor, which is smooth and unilateral). Homovanillic acid (HVA), a breakdown product of dopamine, inc.in urine. Bombesin +ve . Less likely to develop hypertension. Associated with overexpression of N-myc oncogene.

Answer 469

B) Reason BOUNDARIES• Laterally: The biceps femoris muscle above and the lateralhead of the gastrocnemius and plantaris muscles below.• Medially: The semimembranosus and semitendinosusmuscles above and the medial head of the gastrocnemiusmuscle below

Answer 470

A) Reason FRACTURES OF THE HUMERUS AND INJURYTO THE RADIAL NERVEThe radial nerve can be damaged where it lies in thespiral groove on the posterior surface of the shaft ofthe humerus under cover of the triceps muscle.

Answer 471

D) Reason Anabolic effects of insulin:Inc. glucose transport in skeletal muscle and adipose tissueInc. glycogen synthesis and storageInc. triglyceride synthesisInc. lipoprotein lipase in adipose tissueInc. protein synthesis (muscles, proteins)Inc. cellular uptake of K+ and amino acids.

Answer 472

C) Reason • Muscles for Flexion at Knee: Biceps femoris, semitendinosus, and semimembranosus muscles.

Answer 473

E) Reason SUBMANDIBULAR GLANDThe submandibular gland consists of a mixture of serousand mucous acini. It lies beneath the lower border of thebody of the mandible and bellies of digastric. It is divided into superficial anddeep parts by the mylohyoid muscle.

Answer 474

D) Reason Cartilage is a connective tissue composed of cells (chondrocytes) and fibres (collagen or yellow elastic) embedded in a firm, gel-like matrix which is rich in a mucopolysaccharide

Answer 475

C) Reason There is considerable variation in the rate of liver metabolism of individual amide compounds, with prilocaine (fastest) > lidocaine > mepivacaine > ropivacaine ≈ bupivacaine and levobupivacaine (slowest).

Answer 476

E) Reason POSTERIOR TRIANGLEThe posterior triangle is bounded posteriorly by the trapezius muscle, anteriorly by the sternocleidomastoid muscle,and inferiorly by the clavicle. Two most important structures in it are the spinal part of acessary nerve and Subclavian vein.

Answer 477

D) Reason Small vessel disease (diffuse thickening of basement membrane) retinopathy (hemorrhage, exudates, microaneurysms, vessel proliferation) A, glaucoma, nephropathy (nodular sclerosis, progressive proteinuria, chronic renal failure, arteriolosclerosis leading to hypertension, Kimmelstiel-Wilson nodules)

Answer 478

B) Reason Early distal convoluted tubule (DCT)—actively reabsorbs Na+, Cl-. Makes urine hypotonic.PTH—↑ Ca2+/Na+ exchange → Ca2+reabsorption.Secrets H ions.5–10% Na+ reabsorbed.

Answer 479

A) Reason Staphylococcus epidermidisInfects prosthetic devices and intravenous catheters by producing adherent biofilms. Component of normal skin flora; contaminates blood cultures. Novobiocin sensitive.

Answer 480

C) Reason Lymph DrainageThe lymph drains from the prostate goes into the internal iliac and external iliec nodes.

Answer 481

E) Reason Acute pulmonary edema. The cause of this is stillunknown, but a suggested answer is the following:The severe hypoxia causes the pulmonary arteriolesto constrict potently, but the constriction is muchgreater in some parts of the lungs than in otherparts, so that more and more of the pulmonaryblood flow is forced through fewer and fewer stillunconstricted pulmonary vessels.

Answer 482

E) Reason Gluteus minimus is preferred answer here.

Answer 483

B) Reason Ameloblastoma (adamantinoma) is an epithel ial tumor arising from precursor cells of the enamel organ. (1) Most frequently, this tumor occurs in the mandible. It usually appears in individuals younger than 35 years of age

Answer 484

E) Reason Medial lesions—Lesions involving midline structures (vermal cortex, fastigial nuclei) and/or the flocculonodular lobe result in truncal ataxia, nystagmus, and head tilting.

Answer 485

B) Reason Viridans streptococci are α-hemolytic. They are normal flora of the oropharynx and cause dental caries (Streptococcus mutans) andsubacute bacterial endocarditis at damaged valves (S. sanguinis)

Answer 486

A) Reason Osteoporosis Trabecular (spongy) bone loses mass and interconnections despite normal bone mineralization and lab values (serum Ca2+ and PO43-). Diagnosis by a bone mineral density test (DEXA) with a T-score of ≤ -2.5. Can be caused by long-term exogenous steroid use.Can lead to vertebral crush fractures—acute back pain, loss of height, kyphosis

Answer 487

E) Reason Cirrhosis is a descriptive term for chronic liver disease characterized by generalized disorganization of hepatic architecture with scarring and nodule formation. Liver cell damage, regenerative activity, and generalized fibrosis reSUlting in a nodular pattern are also characteristic.

Answer 488

B) Reason Fibrocartilage has type I collagen in addition to type II, giving it greater resistance to being stretched (tensile strength), and is the type of cartilage found in intervertebral disks of the vertebral column and the menisci of the knee, and may form the attachment of ligaments and tendons to bone

Answer 489

D) Reason Release of norepinephrine from a sympathetic nerve ending is modulated by norepinephrine itself, acting on presynaptic α2-autoreceptors, angiotensin II, and other substances. It has positive chronotropic effect on heart.

Answer 490

E) Reason 3rd degree (complete):The atria and ventricles beat independently of each other. Both P waves and QRS complexes are present, although the P waves bear no relation to the QRS complexes. The atrial rate is faster than the ventricular rate.

Answer 491

B) Reason Branches from the Great Splanchnic nerves supply the viscera of the Abdominal cavity. Sympathetics to the foregut and midgut (thoracic splanchnic nerves: T5-T12) and to the hindgut and pelvic viscera (lumbar splanchnic nerves: L1-L2) synapse in collateral ganglia

Answer 492

A) Reason Glucocorticoid secretion ■ oscillates with a 24-hour periodicity or circadian rhythm.■ For those who sleep at night, cortisol levels are highest just before waking (ª8 am) and lowest in the evening (≈12 midnight).

Answer 493

C) Reason L1—at the inguinal ligament.L4—includes the kneecaps.S2, S3, S4—erection and sensation of penile and anal zones

Answer 494

A) Reason FIBROADENOMA A. Tumor of fibrous tissue and glands by desmoplasia B. Most common benign neoplasm of the breast; usually seen in premenopausal women C. Presents as a well-circumscribed, mobile marble-like mass

Answer 495

C) Reason ROTATOR CUFF TENDINITISThe rotator cuff is a common site of tendinitis and cancause severe pain in the shoulder region.

Answer 496

B) Reason Anemia of chronic disease: Is an example of normocytic hypochromic anemia, Inflammation inc. hepcidin (released by liver, binds ferroportin on intestinal mucosal cells and macrophages, thus inhibiting iron transport) dec. release of iron from macrophages.

Answer 497

C) Reason Common in northeastern United States.Initial symptoms—erythema chronicum migrans B, flu-like symptoms, +/- facial nerve palsy.Later symptoms—monoarthritis (large joints) and migratory polyarthritis, cardiac (AV nodal block), neurologic (encephalopathy, facial nerve palsy, polyneuropathy).Treatment: doxycycline, ceftriaxone.

Answer 498

B) Reason A total of 400-500 cc of CSF is produced per day; most important step is the first one that is ultrafiltration of Na; ventricles and subarachnoid space contain 90-150 cc, so all of CSF is turned over 2-3 times per day.

Answer 499

A) Reason Important Relations, Right Kidney■ Anteriorly: The suprarenal gland, the liver, the second part of the duodenum, and the right colic flexure ■ Posteriorly: The diaphragm; the costodiaphragmatic recess of the pleura; the 12th rib; and the psoas, quadratus lumborum, and transversus abdominis muscles.

Answer 500

E) Reason Left anterior descending artery (LAD)—supplies anterior 2/3 of interventricular septum, anterior papillarymuscle, and anterior surface of left ventricle (Lead 4 & 5 are lateral leads).

Answer 501

E) Reason In neonates, due to immature sutures, their fontanelle become prominent in dehydrated states, that is why, bregma (anterior fontanelle) best to assess dehydration status.

Answer 502

A) Reason Cervical polyps are inflammatory proliferations of cervical mucosa; they are not true neoplasms. Most common of these polyps are the squamous by Metaplasia of the cervical epithelium.

Answer 503

E) Reason BOUNDARIES OF THE EPIPLOIC FORAMEN• Anteriorly: Free border of the lesser omentum, the bileduct, the hepatic artery, and the portal vein.• Posteriorly: Inferior vena cava.• Superiorly: Caudate process of the caudate lobe of theliver.• Inferiorly: First part of the duodenum.

Answer 504

C) Reason Sole of FootThe muscles of the sole are usually described in four layers (from inferior to superior).

Answer 505

C) Reason Associated with:Inc. susceptibility to infectionPrimary amyloidosis (AL)Punched-out lytic bone lesions on x-ray AM spike on serum protein electrophoresisIg light chains in urine (Bence Jones protein) Rouleaux formation (RBCs stacked like poker chips in blood smear)

Answer 506

C) Reason The primary centre for the shaft appears near its middle in the eighth week of intrauterine life, andgradually extends towards the ends.

Answer 507

A) Reason SENSORY INNERVATION• Anterior two thirds: The lingual nerve (general sensation) and chorda tympani (taste).• Posterior third: The glossopharyngeal nerve (general sensation and taste).

Answer 508

D) Reason The sclera is the external layer and continues anteriorly as the cornea, which is transparent (stratified squamous non keratinized epithelium) and allows light to enter the eye. The intermediate choroid layer is highly vascularized and pigmented.

Answer 509

E) Reason THYMUS:The thymus is a lymphoid tissue with respiratory epithelium, is divided into a distinct cortex and medulla. The thymus serves as a site of maturation ofT-lymphocyte precursors after they exit from the bone marrow and arrive at the thymus via blood circulation.

Answer 510

C) Reason Ewing sarcoma:Boys < 15 years old.Commonly appears in diaphysis of long bones, pelvis, scapula, and ribs.

Answer 511

D) Reason Clinical features include Bone pain with hypokalemia and hypercalcemia-Neoplastic plasma cells activate the RANK receptor on osteoclasts, leading to bone destruction. Lytic, "punched-out" skeletal lesions are seen on x-ray, especially in the vertebrae and skull; increased risk for fracture. Presents with polyuria, bone pain and lytic lesions.

Answer 512

C) Reason All the features given in scenario are characteristics of shock (low BP and tachycardia) while H/O surgery points to the Toxemic shock.

Answer 513

A) Reason Ossification begins in the medial epicondyle in the fourth year in females, sixth in males, and in the lateralepicondyle about the 12th year.

Answer 514

E) Reason For descriptive purposes, the midbrain may be divided into a dorsaltectum and right and left cerebral peduncles, each of which is further divided into a ventral crus cerebriand a dorsal tegmentum by a pigmented lamina, the substantia nigra.

Answer 515

B) Reason Parkinson —Tremor (at rest—e.g., pill-rolling tremor), cogwheel Rigidity, expressionless face,Akinesia (or bradykinesia), Postural instability and Shuffling gait.

Answer 516

D) Reason Posterior descending/interventricular artery (PDA)—supplies posterior 1/3 of interventricular septum (lead 1-4 are the anterior chest leads) and posterior walls of ventricles.

Answer 517

C) Reason LYMPH DRAINAGEf• Tip: Submental lymph nodes.• Sides of anterior two thirds: Submandibular lymphnodes.• Posterior third: Deep cervical lymph nodes.

Answer 518

B) Reason Pubofemoral LigamentThe pubofemoral ligament is triangular in shapeThe base is attached above to the superior ramus of the pubis, and the apex is attached below to the lower end of theintertrochanteric line.

Answer 519

D) Reason Prolactin—induces and maintains lactation and reproductive function. Oxytocin—assists in milk letdown; also promotes uterine contractions

Answer 520

E) Reason Vitamin E (tocopherol/tocotrienol)FUNCTION: Antioxidant (protects erythrocytes and membranes from free radical damage).

Answer 521

E) Reason AQUEOUS HUMOR:The aqueous humor is a clear fluid formed by ultrafiltration that fills the anterior andthe posterior chambers.

Answer 522

D) Reason Lateral Longitudinal ArchThe lateral longitudinal arch is formed by the calcaneum,the cuboid, and the fourth and the fifth metatarsal bones.

Answer 523

D) Reason TRIBUTARIES• Two anterior visceral tributaries (the hepatic veins).• Three lateral visceral tributaries: the right suprarenal vein(the left vein drains into the left renal vein), renal veins,and right testicular or ovarian vein (the left vein drains intothe left renal vein).

Answer 524

D) Reason Quiet ExpirationQuiet expiration is a passive process accomplished by theelastic recoil of the lungs and the relaxation of the intercostal muscles and diaphragm.

Answer 525

B) Reason A subdural hematoma results from head trauma that tears superficial ("bridging") cerebral veins at the point where they enter the superior sagittal sinus. A subdural hemorrhage occurs between the meningeal dura and the arachnoid.

Answer 526

C) Reason Standard deviation = how much variability exists from the mean in a set of values.Standard error of the mean = an estimation of how much variability exists between the sample mean and the true population mean.

Answer 527

A) Reason Ethanol is widely used to clean the skin before immunization or venipuncture. It actsmainly by disorganizing the lipid structure in membranes, but it denatures proteins aswell. Ethanol requires the presence of water for maximal activity (i.e., it is far moreeffective at 70% than at 100%).

Answer 528

E) Reason All the carbohydrates given in the list are monosacchrides and need no further digestion being simplest except Sucrose that is discchride and must be digested further to a mono sugar before absorption.

Answer 529

A) Reason Features in scenario are of CRF in which JG cells are damaged as well. JG cells (modified smooth muscle of afferent arteriole) and the macula densa (NaCl sensor, part of the distal convoluted tubule). JG cells secrete renin in response to dec. renal blood pressure, dec. NaCl delivery to distal tubule, and inc. sympathetic tone (β1)

Answer 530

B) Reason The acrosome, which is located over the anterior half of the nucleus, is derived from the Golgi complex of the spermatid and contains several hydrolytic enzymes such as hyaluronidase, neuraminidase, and acid phosphatase; these enzymes dissociate cells of the corona radiata and digest the zona pellucida of the recently produced secondary oocyte.

Answer 531

D) Reason Listeria monocytogenes:Facultative intracellular microbe; acquired by ingestion of unpasteurized dairy products and deli meats, via transplacental transmission, or by vaginal transmission during birth.

Answer 532

B) Reason A pneumotaxic center, located dorsally in the nucleusparabrachialis of the upper pons, transmits signals tothe inspiratory area. The primary effect of this centeris to control the “switch-off” point of the inspiratoryramp, thus controlling the duration of the filling phaseof the lung cycle

Answer 533

A) Reason • The corticospinal tract is involved in the voluntary contraction of skeletal muscle, especially in the distal extremities. This pathway consists of 2 neurons, an upper motor neuron, and a lower motor neuron

Answer 534

E) Reason Posterior pituitary (neurohypophysis)Secretes vasopressin (antidiuretic hormone, or ADH) and oxytocin, made in the hypothalamus and shipped to posterior pituitary via neurophysins (carrier proteins). Derived from neuroectoderm

Answer 535

A) Reason LOBULAR CARCINOMA IN SITU (LCIS) A. Malignant proliferation of cells in lobules with no invasion of the basement membrane B. LCIS does not produce a mass or calcifications and is usually discovered incidentally on biopsy.

Answer 536

D) Reason Medial lesions—Lesions involving midline structures (vermal cortex, fastigial nuclei) and/or the flocculonodular lobe result in truncal ataxia, nystagmus, and head tilting.

Answer 537

C) Reason The internal anal sphincter is circular smooth muscle that surrounds the anal canal. The sympathetics (lumbar splanchnics) increase the tone of the muscle and the parasympathetics (pelvic splanchnics) relax the muscle during defecation.

Answer 538

D) Reason In a burn patient, ECF and plasma is lost along with the plasma proteins especially the albumin. This state of hypoalbuminemia causes edema.

Answer 539

D) Reason TESTS: Fasting serum glucose of >126mg/dl is diagnostic , oral glucose tolerance test, HbA1c (reflects average blood glucose over prior 3 months).

Answer 540

E) Reason Complience is defined as the adherence of patients to the treatment and it largely depends upon knowledge of pt about disease and drug and its side effects.

Answer 541

B) Reason MEMBRANOUS URETHRAThe membranous urethra passes through the urogenital diaphragm and is surrounded by the sphincter urethrae. It is the shortest and least dilatable part of the urethra.

Answer 542

B) Reason BOUNDARIES OF THE EPIPLOIC FORAMEN• Anteriorly: Free border of the lesser omentum, the bileduct, the hepatic artery, and the portal vein.• Posteriorly: Inferior vena cava.• Superiorly: Caudate process of the caudate lobe of theliver.• Inferiorly: First part of the duodenum.

Answer 543

E) Reason All the features given in scenario are suggestive of shock (hypotension and tachycardia) while H/O wound previouly fevers the condition of being sepsis.

Answer 544

D) Reason Aortic arch barorecptors respond to inc but not to decreased while carotid sinus receptors dectect increase as well deceased in arterial pressure

Answer 545

E) Reason Veinsof Stomach:The veins drain into the portal circulation. The right and leftgastric veins drain into the portal vein. The short gastric and the left gastroepiploic veins drain into the splenic vein,and the right gastroepiploic vein drains into the superiormesenteric vein.

Answer 546

B) Reason Cachexia Weight loss, muscle atrophy, and fatigue that occur in chronic disease (e.g., cancer, AIDS, heart failure, TB). Mediated by TNF-α (nicknamed cachectin), IFN-γ, and IL-6

Answer 547

C) Reason Anterior pituitary (adenohypophysis)Secretes FSH, LH, ACTH, TSH, prolactin, GH, melanotropin (MSH). Derived from oral ectoderm (Rathke pouch)

Answer 548

C) Reason • Subarachnoid space lies between the arachnoid and pia mater containing CSF: site of subarachnoid hemorrhage (described later).

Answer 549

B) Reason The placenta permits exchange of nutrients and removal of waste products between maternal and fetal circulations. The fetal component consists of the chorionic plate and villi. The maternal component is decidua basalis. Maternal blood is separated from fetal blood by the cytotrophoblast and syncytiotrophoblast.

Answer 550

A) Reason The pharyngeal tonsil is an aggregate of nodular and diffuse lymphatic tissue within the posterior wall of the nasopharynx.

Answer 551

E) Reason Examples are Na+-glucose cotransport in the small intestine especially jejunum and renal early proximal tubule and Na+–K+ –2Cl– cotransport in the renal thick ascending limb.

Answer 552

B) Reason • Eversion (opposite movement of the foot so that the solefaces laterally): Peroneus longus, peroneus brevis, peroneus tertius, and lateral tendons of extensor digitorumlongus muscles.

Answer 553

B) Reason Forced ExpirationForced expiration is an active process accomplished bycontraction of the muscles of the anterior abdominal wall(forcing the relaxed diaphragm upward by raising intraabdominal pressure) and contraction of the quadratuslumborum (pulling the twelfth rib downward).

Answer 554

D) Reason Femoral ArteryThe femoral artery is a continuation of the external iliac artery. It begins behind the inguinal ligament, where itlies midway between the anterior superior iliac spine and thesymphysis pubis (the site for taking a femoral pulse).

Answer 555

C) Reason A chest pain that doesn"t change with any body movements or respiration is a pain of myocardium While pain of muskulosketal origin changes with movements.

Answer 556

E) Reason In hyperventilation, CO2 is washed out leading to respiratory alkalosis. Conc. of H ions decreases and then plasma proteins use Ca for binding in place of H laeding hypocalcemia (and tetanic spasms).

Answer 557

A) Reason Na+, K+ -ATPase (or Na+–K+ pump) in cell membranes transports Na+ from intracellular to extracellular fluid and K+ from extracellular to intracellular fluid; it maintains low intracellular [Na+] and high intracellular [K+].

Answer 558

A) Reason Its boundaries are as follows:• Superiorly: The inguinal ligament.• Laterally: The sartorius muscle.• Medially: The adductor longus muscle

Answer 559

E) Reason Broca"s Area lesion: Nonfluent aphasia with intact comprehension.Broca area—inferior frontal gyrus of frontal lobe.

Answer 560

E) Reason he facial nerve enters the internal acoustic meatus and thenthe facial canal. It emerges through the stylomastoid foramen, and it enters the parotid salivary gland.

Answer 561

B) Reason Extracellular fluid (ECF)■ is one-third of TBW.■ is composed of interstitial fluid and plasma. The major cation of ECF is Na+.■ The major anions of ECF are Cl- and HCO3.

Answer 562

A) Reason Innate defenses can be classified into three major categories: (1)physical barriers, such as intact skin and mucous membranes; (2) phagocytic cells,such as neutrophils, macrophages, and natural killer cells; and (3) proteins, such ascomplement, lysozyme, and interferon

Answer 563

A) Reason K+-sparing diuretics: Spironolactone and eplerenone; Triamterene, and Amiloride. CLINICAL USE: Hyperaldosteronism, K+ depletion, CHF.

Answer 564

D) Reason Causes of Long QT interval:1. Bradycardia 2. Hypocalcemiaor hypoglycemia 3. Acute MI 4. Acute myocarditis 5. Cerebrovascular accident 6. Hypertrophic cardiomyopathy 7. Hypothermia

Answer 565

D) Reason When asked technique mark dilution technique. When asked law then mark Ficks law.

Answer 566

A) Reason Relation of Trachea in Superior mediastinum: • Right side: Azygos vein, right vagus nerve, and pleura.• Left side: Arch of the aorta, left common carotid, left subclavian arteries, left vagus nerve, left phrenic nerve, andpleura.

Answer 567

E) Reason Celiac Artery (Trunk):The celiac artery is a short, large artery that arises from thefront of the abdominal aorta as it emerges through the diaphragm. It has three terminal branches: the leftgastric, the splenic, and the hepatic arteries.

Answer 568

C) Reason MoA: Calcineurin inhibitor; binds cyclophilin. Blocks T cell activation by preventing IL-2 transcription. USES: Transplant rejection prophylaxis, psoriasis, rheumatoid arthritis. TOXICITY: Nephrotoxicity,hypertension, hyperlipidemia, hyperglycemia, tremor, hirsutism, gingival hyperplasia.

Answer 569

C) Reason The cerebellum consists of a midline vermis and 2 lateral cerebellar hemispheres. The cerebellar cortex consists of multiple parallel folds that are referred to as folia. The cerebellar cortex contains several maps of the skeletal muscles in the body

Answer 570

E) Reason DIC: Widespread activation of clotting leads to a deficiency in clotting factors, which creates a bleeding state.Causes: Sepsis (gram-negative), Trauma, Obstetric complications, acute Pancreatitis, Malignancy, Nephrotic syndrome, Transfusion (STOP Making New Thrombi).Labs: schistocytes, increased fibrin split products (d-dimers), decreased fibrinogen, decreased factors V and VIII.

Answer 571

B) Reason Na/K ATPase (or Na+/K+ pump) in cell membranes transports Na+ from intracellular to extracellular fluid and K+ from extracellular to intracellular fluid; it maintains low intracellular [Na+] and high intracellular [K+].

Answer 572

E) Reason Serotonin (5-hydroxytryptamine)■ causes arteriolar constriction and is released in response to blood vessel damage to help prevent blood loss.It is destroyed at lungs.■ has been implicated in the vascular spasms of migraine headaches.

Answer 573

D) Reason Cardiac muscle action potential has a plateau, which is due to Ca2+ influx and K+ efflux; myocyte contraction occurs due to Ca2+-induced Ca2+ release from the sarcoplasmic reticulum

Answer 574

D) Reason Dermatomes: C2—posterior half of a skull “cap.”C3—high turtleneck shirt.C4—low-collar shirt.T1--Lower end of clavicle to sternumT4—at the nipple.T7—at the xiphoid process.T10—at the umbilicus (important for early appendicitis pain referral).L1—at the inguinal ligament.L4—includes the kneecaps.S2, S3, S4—erection and sensation of penile and anal zones.

Answer 575

E) Reason Chi-square (χ²) Checks difference between 2 or more percentages or proportions of categoricaloutcomes (not mean values). It uses 2 x 2 table.

Answer 576

E) Reason The submandibular ganglion is a parasympathetic ganglionthat lies deep to the submandibular salivary gland and is attached to the lingual nerve by small nerves. Preganglionicparasympathetic fibers reach the ganglion from the facialnerve via the chorda tympani and the lingual nerves.Postganglionic secretomotor fibers pass to the submandibular and the sublingual salivary glands.

Answer 577

B) Reason Pyloric antrum: This extends from the incisura angularisto the pylorus. Its removal can lead to decreased complience of the stomach.

Answer 578

E) Reason The duodenum begins at the pyloric sphincter ofthe stomach, and it ends by becoming continuous with the jejunum. It smoothens the gastric emptying by sphincter. It removal as in cases of Whipple Procedure, can lead to rapid gastric emptying.

Answer 579

E) Reason Drugs that block the activity ofdopaminergic pathways include older antipsychotics (eg, chlorpromazine, haloperidol), which maycause dystonia and parkinsonian symptoms.

Answer 580

C) Reason O2 percentage in air is 21, so 700 x 21/100=147Nitrogen percentage is 79, so 700 x 79/100=553

Answer 581

A) Reason MECHANISM Thiazide diuretic. Inhibits NaCl reabsorption in early distal tubule, decreased diluting capacity of the nephron. Decreased Ca2+ excretion.

Answer 582

E) Reason Remember the sequence Glutathione is most potent anti oxident if given in options then Vit. E (correct here) and then Vit. C

Answer 583

D) Reason FINDINGS Hypertension, weight gain, moon facies, truncal obesity B, buffalo hump, hyperglycemia (insulin resistance), skin changes (thinning, striae), osteoporosis, amenorrhea, and immune suppression.

Answer 584

E) Reason pain and temperature sensation is carried by opposite side spinothalmic tract at L1 level.

Answer 585

D) Reason Pseudohypoparathyroidism (Albright hereditary osteodystrophy)—autosomal dominant unresponsiveness of kidney to PTH. Hypocalcemia, shortened 4th/5th digits, short stature.

Answer 586

A) Reason Complications in sickle cell disease (SS):1. Aplastic crisis (due to parvovirus B19).2. Autosplenectomy (Howell-Jolly bodies) 3. risk of infection with encapsulated organisms; early splenic dysfunction occurs in childhood.4. Splenic sequestration crisis.5. Salmonella osteomyelitis.

Answer 587

E) Reason Hematoxylin is a blue dye which stains basophilic substrates that are the acidic cellular components such as DNA, RNA and ribosomes. Hematoxylin stains nuclei blue, and may tint the cytoplasm of cells with extensive mRNA in their cytoplasm.

Answer 588

C) Reason Median nerve lesions commonly result from supracondylar fractures of the humerus and from wounds just proximal to the flexor retinaculum. Among the clinical signs, the muscles of the thenar eminence areparalyzed and wasted so that the eminence is flattened and the thumb is laterally rotated and adducted. The hand looks apelike.

Answer 589

B) Reason Values of the different deep tendon reflexes are as: Bicep C5-6, Tricep C6-7, Jaw jerk CN V, and knee jerk as L4 and ankle jerk as S1.

Answer 590

A) Reason Mononuclear cell and fibroblast mediated; characterized by persistent destruction and repair. Associated with blood vessel proliferation, fibrosis. Granuloma: nodular collections of epithelioid macrophages and giant cells. Acute on chronic inflamation can lead to abcess formation.

Answer 591

B) Reason The upper slips of muscle merge and fuse with the slips of Serratus anterior. The inferior slips interdigitate with Latissimus dorsi.

Answer 592

B) Reason Newborns are initially asymptomatic because of Increased HbF and decreased HbS.Heterozygotes (sickle cell trait) have resistance to malaria.

Answer 593

C) Reason Obligate anaerobes give foul smelling discharge, Examples include Clostridium, Bacteroides, and Actinomyces. They lack catalase and/or superoxide dismutase and are thus susceptible to oxidative damage. Generally foul smelling (short-chain fatty acids), are difficult to culture, and produce gas in tissue (CO2 and H2).

Answer 594

B) Reason TOXICITY Gastric ulceration, tinnitus (CN VIII). Chronic use can lead to acute renal failure, interstitial nephritis, and upper GI bleeding. Reye syndrome in children with viral infection. Overdose causes respiratory alkalosis initially, which is then superimposed by metabolic acidosis.

Answer 595

B) Reason Arteries contributing to Circle of Willis are: anterior communicating,anterior cerebral, internal carotid, posterior communicating, posterior cerebral, and basilar (formed by the junctionof the two vertebral arteries).Cortical and central branches arise from thecircle and supply the brain.

Answer 596

A) Reason Centrioles are the eukaryotic organelles that are composed of 9 circular arrangement of clusters of triad of microtubules and function as mitotic spindle formation

Answer 597

C) Reason Complications of total parenteral nutrition (TPN) include sepsis, thrombosis, hyponatraemia, hyperglycaemia and liver damage. To minimize sepsis, the central venous catheter is tunnelled with a subcutaneous Dacron cuff at the exit site to reduce the risk of line infection.

Answer 598

A) Reason Fibrocartilage has type I collagen in addition to type II, giving it greater resistance to being stretched (tensile strength), and is the type of cartilage found in intervertebral disks of the vertebral column and the menisci of the knee, and may form the attachment of ligaments and tendons to bone

Answer 599

E) Reason The cardiac conduction system located subendocardially is a specialized group of myocardial cells that initiates the periodic contractions of the heart due to their ability to depolarize at a faster rate than other cardiac myocytes.

Answer 600

B) Reason Each lung is supplied by the pulmonary plexus. Theplexus is formed by branches of the sympathetic trunk (T3-T4) andreceives parasympathetic fibers from the vagus nerve (CN X).

Answer 601

C) Reason Normal percentage of the major nutrients in a normal diet are Carbohydrates 45-65 %, Proteins 25-40% , Lipid as 15-20%.

Answer 602

D) Reason MECHANISM: Block voltage-dependent L-type calcium channels of cardiac and smooth muscle, thereby reduce muscle contractility.Vascular smooth muscle—amlodipine = nifedipine > diltiazem > verapamil.Heart—verapamil > diltiazem > amlodipine = nifedipine (verapamil = ventricle).

Answer 603

D) Reason Cardiac Cycle= 1 minute/ number of beats= 60 sec/ 72= 0.8 sec. As heart rate doubles the cycle will become half e.g: cardiac cycle= 60/144= 0.4 sec.

Answer 604

E) Reason in restrictive lung disease FEV1/FVC can be increased or normal.

Answer 605

D) Reason Flaccid paralysis, floppy baby; toxin prevents release of stimulatory (ACh) signals at neuromuscular junctions leading to flaccid paralysis and can cause respiratory muscle paralysis.

Answer 606

D) Reason 1. Awake (eyes open) Alert, active mental concentration Beta (highest frequency, lowest amplitude)2. Awake (eyes closed) Alpha3. Non-REM sleepStage N1 (5%) Light sleep- theta waves

Answer 607

B) Reason Sarcoidosis is Associated with restrictive lung disease (interstitial fibrosis), erythema nodosum, lupus pernio, Bell palsy, epithelioid granulomas containing microscopic Schaumann and asteroid bodies, uveitis, and hypercalcemia (due to increased 1α hydroxylase–mediated vitamin D activation in macrophages). Treatment: steroids.

Answer 608

E) Reason A Pneumotaxic Center Limits theDuration of Inspiration and Increasesthe Respiratory Rate: A pneumotaxic center, located dorsally in the nucleusparabrachialis of the upper pons, transmits signals tothe inspiratory area.

Answer 609

A) Reason The sensory supply from most of the dorsal surface of the foot is provided by the superficial fibular nerve, except between the great and second toes, which is supplied by the deep fibular nerve.

Answer 610

A) Reason Water and electrolytes are reabsorbed in large intestine esp. the colon. When there is any abnormality of this absorption mechanism, it leads to dirrohea and electrolytes loss

Answer 611

E) Reason Posterior cord: Upper subscapular nerveThoracodorsal nerve, Lower subscapular nerveAxillary nerve (C5, 6)..supplies deltoid and teres minor muscles.Radial nerve (C5, 6, 7, 8; T1)

Answer 612

B) Reason SA and AV nodes are usually supplied by RCA. Infarct may cause nodal dysfunction (bradycardia or heart block)

Answer 613

B) Reason Clinical Uses of Fluroquinolones: Gram-negative rods of urinary and GI tracts (including Pseudomonas), especially Ciprofloxacin, Neisseria, some gram-positive organisms.

Answer 614

C) Reason Abdominal distention might be due to intra-abdominal bleed after surgery leading to hypovolemic shock. Moreover, sepsis takes time.

Answer 615

E) Reason JG cells (modified smooth muscle of afferent arteriole) and the macula densa (NaCl sensor, part of the distal convoluted tubule). JG cells secrete renin in response to decreased renal blood pressure, decreases NaCl delivery to distal tubule, and increases sympathetic tone (β1).

Answer 616

A) Reason The olfactory nerves arise from olfactory nerve cells in theupper part of the nasal mucous membrane that is replaced continually.

Answer 617

A) Reason Decreased cardiac output leads to Hypoxia. This supplement the baroreceptor mechanism by increasing sympathetic outflow to the heart and blood vessels. This increased outflow causes cellular edema.

Answer 618

E) Reason Excitatory pathway—cortical inputs stimulate the striatum, stimulating the release of GABA, which disinhibits the thalamus via the GPi/SNr (increasess motion).

Answer 619

C) Reason Causes of Low voltage QRS (less than 5 mm in leads I, II, III and <10 mm in chest leads):1. Improper standardization2. Obesity or thick chest wall3. Pericardial effusion4. Emphysema5. Chronic constrictive pericarditis6. Hypothyroidism7. Hypothermia

Answer 620

A) Reason Measurement of renal plasma flow (RPF)—clearance of para-aminohippuric acid (PAH)■ PAH is filtered and secreted by the renal tubules.■ Clearance of PAH is used to measure RPF.

Answer 621

E) Reason Nutmeg liver Due to backup of blood into liver. Commonly caused by right-sided heart failure and Budd-Chiari syndrome. The liver appears mottled like a nutmeg. If the condition persists, centrilobular congestion and necrosis can result in cardiac cirrhosis

Answer 622

A) Reason Ideally, ventilation is matched to perfusion (i.e., V/Q = 1) in order for adequate gas exchange.Lung zones:1. Apex of the lung—V/Q = 3 (wasted ventilation)2. Base of the lung—V/Q = 0.6 (wasted perfusion)Both ventilation and perfusion are greater at the base of the lung than at the apex of the lung

Answer 623

D) Reason Neoplastic progression Hallmarks of cancer—evasion of apoptosis, growth signal self-sufficiency, anti-growth signal insensitivity, sustained angiogenesis, limitless replicative potential, tissue invasion, and metastasis. Metastasis is especially prominent in malignant lesions.

Answer 624

D) Reason The parotids are entirely serous salivary glands with septa and striated ducts that drain inside each cheek through Stensen"s ducts which open above the second upper molar tooth

Answer 625

C) Reason Gap junctions:■ are present at the intercalated disks.■ are low-resistance paths between cells that allow for rapid electrical spread of action potentials.■ account for the observation that the heart behaves as an electrical syncytium.

Answer 626

B) Reason Pulsus paradoxus decrease in amplitude of systolic blood pressure by ≥ 10 mmHg during inspiration. Seen in cardiac tamponade, asthma, obstructive sleep apnea, pericarditis, and croup.

Answer 627

C) Reason All of the β blockers used clinically are competitive pharmacologic antagonists. Propranolol is theprototype. Drugs in this group are usually classified into subgroups on the basis of 1 selectivity.

Answer 628

B) Reason Insulin-dependent glucose transporters:GLUT-4: adipose tissue (increases lipoprotein lipase) and skeletal muscle.

Answer 629

A) Reason Norepinephrine effects are α1 > α2 > β1 ( β1 increase heart rate, increase contractility, increase renin release, increase lipolysis) Clinical use are Hypotension (but decreases renal perfusion)

Answer 630

C) Reason HCO3- leaves the RBCs in exchange for Cl- (chloride shift) and i is transported to the lungs in the plasma. HCO3- is the major form in which CO2 is transported to the lungs.

Answer 631

D) Reason The posterior division descends through the obturatorexternus muscle and passes behind the adductor brevis andin front of the adductor magnus muscles

Answer 632

A) Reason Pulmonary embolism: V/Q mismatch leading to hypoxemia and cause respiratory alkalosis. Sudden-onset dyspnea, chest pain, tachypnea. May present as sudden death

Answer 633

C) Reason • The inferior thyroid artery ascends to reach the posterior surface of the thyroid gland, where it is closely relatedto the recurrent laryngeal nerve. The inferior thyroidartery supplies the thyroid, upper 1/3rd of esophagus and the inferior parathyroidglands.

Answer 634

A) Reason A primary peristaltic contraction creates an area of high pressure behind the food bolus. The peristaltic contraction moves down the esophagus and propels the food bolus along. Gravity accelerates the movement.d. A secondary peristaltic contraction by the dilatation of esophagus clears the esophagus of any remaining food.

Answer 635

E) Reason Associated with Aschoff bodies (granuloma with giant cells [blue arrows in ]), Anitschkow cells (enlarged macrophages with ovoid, wavy, rod-like nucleus [red arrow in A]), increased ASO titers. Immune mediated (type II hypersensitivity); not a direct effect of bacteria. Antibodies to M protein cross-react with self antigens.

Answer 636

C) Reason Clonidine MoA: It enhance alpha 2 responses at presynaptic cleft. Clinical: Hypertensive urgency (limited situations); does not decrease renal blood flowADHD, severe pain, and a variety of off label indications (e.g., ethanol and opioid withdrawal)

Answer 637

C) Reason Risk factors for Cervical dysplasia : multiple sexual partners (#1), smoking, early sexual intercourse, multiparty, HIV infection.

Answer 638

A) Reason Nephrotic syndrome includes a group of conditions characterized by increased basement membrane permeability, permitting the urinary loss of plasma proteins, particularly low weight proteins, such as albumin.

Answer 639

B) Reason The glans penis drains into the deep inguinal and the external iliac nodes. The skin of the remainder of the organ drains into the superficial inguinal nodes. The erectile tissuedrains into the internal iliac nodes.

Answer 640

D) Reason After blood loss, fisrt of all, the hemodynamics are corrected due to fast and slow acting mechanisms. Hematopoisis takes larger time and hence CBC is corrected last.

Answer 641

C) Reason Medial lesions—Lesions involving midline structures (vermal cortex, fastigial nuclei) and/or the flocculonodular lobe result in truncal ataxia, nystagmus, and head tilting. These patients also may have a wide-based (cerebellar) gait and deficits in truncal coordination.

Answer 642

C) Reason Shivering is the most potent mechanism for increasing heat production. ■ Cold temperatures activate the shivering response (initial heat production), which is orchestrated by the posterior hypothalamus.

Answer 643

A) Reason CLINICAL USE: Hyperthyroidism. PTU blocks Peripheral conversion, used in Pregnancy because it can"t cross placenta.

Answer 644

B) Reason Chondroblasts (cartilage forming) and chondrocytes (mature cartilage) produce the type II collagen in cartilage. Cartilage covers the articular surfaces of bones, and is found in the ears, nose, larynx, and tracheobronchial tree.

Answer 645

D) Reason Cirrhosis—diffuse fibrosis and nodular regeneration destroys normal architecture of liver , risk for hepatocellular carcinoma (HCC).

Answer 646

C) Reason Intrinsic factor is Vitamin B12–binding protein (required for B12uptake in terminal ileum). Damage to Intrinsic factor or malabsorption due ilial defects causes pernicious anemia.

Answer 647

C) Reason Cryptococcus neoformans:Cryptococcal meningitis (sometimes associated with lymphoma), cryptococcosis. Heavily encapsulated yeast. Not dimorphic. Found in soil, pigeon droppings. Acquired through inhalation with hematogenous dissemination to meninges

Answer 648

B) Reason High doses of conventional sedative-hypnotics, especially alcohols and barbiturates, can causedepression of medullary neurons in deblitated or hypovolumic patients , leading to respiratory arrest, hypotension, and cardiovascularcollapse. These effects are the cause of death in suicidal overdose

Answer 649

A) Reason Associated with Charcot joints, shooting pain, atonic bladder, Argyll Robertson pupils (small bilateral pupils that further constrict to accommodation and convergence, not to light)

Answer 650

C) Reason Ruffini corpuscle are the Encapsulated receptors that carry Pressure sensations and are Slowly adapting receptors.

Answer 651

C) Reason The action of full doses of crurae NM blockers leads directly to respiratory paralysis. Ifmechanical ventilation is not provided, the patient will asphyxiate.

Answer 652

E) Reason PPD positive: if current infection, past exposure, or BCG vaccinated.PPD negative: if no infection or anergic (steroids, malnutrition, immunocompromise) and in sarcoidosis.

Answer 653

B) Reason Small intestine is attached to the mesentery of the small intestine and is placed at its place exept the right hypochondriac region where it is free.

Answer 654

A) Reason Acute inflammation is rapid onset (seconds to minutes), lasts minutes to days by the chemotaxis of the acute inflammatory cells to the site. Outcomes include complete resolution, abscess formation, andprogression to chronic inflammation

Answer 655

D) Reason Best way to measure GFR =inulin ClearanceBest way to measured GFR clinically by =creatinineBest way to estimate GFR = creatinine clearance

Answer 656

E) Reason Sertoli cells (non–germ cells):Secrete inhibin that inhibit FSHSecrete androgen-binding protein that maintain local levels of testosterone.

Answer 657

B) Reason Herniation usually occurs in the lower lumbar (L4/LS or LS/Sl) when pain radiates to posterior of thigh. or lower cervical (CS/C6 or C6/C7) when pain radiates to arm parts of the vertebral column.

Answer 658

E) Reason The major anions of ICF are protein and organic phosphates. While anions of the ECF are the inorganic such as Cl and HCO3.

Answer 659

A) Reason In a patient with heart failure, Mannitol should be given with caution because of risk of precipitating pulmonary edema

Answer 660

A) Reason Blood transfusion risks include infection transmission (low), transfusion reactions, iron overload, hypocalcemia (citrate is a calcium chelator), and hyperkalemia (RBCs may lyse in old blood units leading to hemoglobinurea and hypokalemia)

Answer 661

E) Reason Prolactin is regulated by Dopamine and TRH. Prolactin in turn inhibits its own secretion by increased dopamine synthesis and secretion from hypothalamus.

Answer 662

C) Reason AIDS diagnosis ≤ 200 CD4+ cells/mm3(normal: 500–1500 cells/mm3). HIV-positive with AIDS-defining condition (e.g., Pneumocystis pneumonia) or CD4 percentage < 14%.

Answer 663

A) Reason Ionizing radiation is a classic cause of chronic inflammation and cancer as these damage geneetic material and cellular proteins, as exemplified by the increased incidence of cancers in those exposed to radiation.

Answer 664

A) Reason Dysplasia and carcinoma in situ:Disordered epithelial growth; begins at basal layer of squamocolumnar junction (transition zone) and extends outward. Classified as CIN 1, CIN 2, or CIN 3 (severe dysplasia or carcinoma in situ), depending on extent of dysplasia.

Answer 665

B) Reason Atonic bladder results from lesions to the sacral spinal cord segments or the sacral spinal nerve roots. Loss of pelvic splanchnic motor innervation with loss of contraction of the detrusor muscle results in a full bladder with a continuous d ribble of urine from the bladder.

Answer 666

B) Reason In typhoid and other enteric fevers, infection begins in the small intestine, but few gastrointestinal symptoms occur. Then after few days organisms enter, multiply in themononuclear phagocytes of Peyer’s patches, and then spread to the phagocytes of theliver, gallbladder, and spleen

Answer 667

B) Reason FUNCTION: It is an important stress hormone and functions to increase Blood pressure (upregulates α1-receptors on arterioles and increases sensitivity to norepinephrine and epinephrineIncreases nsulin resistance (diabetogenic)Increases luconeogenesis, lipolysis, and proteolysisDecreases Fibroblast activity (causes striae)Decreases Inflammatory and Immune responses

Answer 668

C) Reason The sinus venosus at the venous end of the heart tube will develop into the coronary sinus and the smooth part of the right atrium.

Answer 669

D) Reason Virulence is a quantitative measure of pathogenicity and is measured by thenumber of organisms required to cause disease. As many people are affected, means more virulent is the organism or its poison.

Answer 670

C) Reason The substantia nigra is the largest nucleus of the midbrain. It appears black to dark brown in the freshly cut brain because nigral cells contain melanin pigments. It is closely related to crus cerebri.

Answer 671

C) Reason Tuberculosis is an example of type 4 delayed HSR and is associated with chronic infection. Its antibodies are attached to the cells.

Answer 672

A) Reason Submucosal plexus (Meissner plexus):■ primarily controls secretion and blood flow by virtue of which it can compensates its blood supply in case of hemmorhage or hypovolumia.

Answer 673

E) Reason Blood Supplyof the Esophagus:• Upper third: Inferior thyroid artery.• Middle third: Branches from the descending thoracicaorta (internal thoracic artery).• Lower third: Left gastric artery.

Answer 674

E) Reason Standard deviation = how much variability exists from the mean in a set of values.Standard error of the mean = an estimation of how much variability exists between the sample mean and the true population mean.

Answer 675

C) Reason Norepinephrine released from a sympathetic nerve ending is modulated by norepinephrine itself, acting on presynaptic α2-autoreceptors, angiotensin II, and other substances.

Answer 676

E) Reason B. Formation of CSF by the choroid plexus epithelium:■ Ultrafiltration of Na ions followed by the Lipid-soluble substances (CO2 and O2) and H2O freely cross the blood–brain barrier and equilibrate between blood and CSF.■ Other substances are transported by carriers in the choroid plexus epithelium. They may be secreted from blood into the CSF or absorbed from the CSF into blood.

Answer 677

C) Reason In lipoproteins, as the percentage of lipids increases the percentage of protein decreases and vice versa. So, protein conc. being highest in HDL and lowest in VLDL.

Answer 678

C) Reason Induced to kill when exposed to a nonspecific activation signal on target cell and/or to an absence of class I MHC on target cell surface (carbohydrates on cell wall).

Answer 679

D) Reason Sometimes, spontaneous discharge occurs without relaxation in someperipheral nerves, often causing muscle “tetany.”

Answer 680

E) Reason Recurrent laryngeal nerves, inferior thyroid veins, carotid arteries & internal jugular veins could be damaged this is a real risk in obese or paediatric patients.

Answer 681

B) Reason Degree of localization/spread based on site and size of 1° lesion, spread to regional lymph nodes, presence of metastases. Based on clinical (c) or pathology (p) findings. Example: cT3N1M0

Answer 682

B) Reason Cataract:Painless, often bilateral, opacification of lens , decreased in vision. Risk factors: increasing age, smoking, EtOH, excessive sunlight, UV light, prolonged corticosteroid use, classic galactosemia, galactokinase deficiency, diabetes (sorbitol), trauma, infection.

Answer 683

A) Reason Diagnosis: Screen patients > 50 years old with colonoscopy or stool occult blood test.“Apple core” lesion seen on barium enema x-ray.CEA tumor marker: good for monitoring recurrence, not useful for screening

Answer 684

A) Reason This is a major parasympathetic nucleus of the brain stem, and it supplies preganglionic fibers innervating terminal ganglia in the thorax and the foregut and midgut parts of the gastrointestinal tract. It damage mainly affects the gastrointestinal tract muscles.

Answer 685

A) Reason During pharyngeal swallowing larynx and the laryngeal part of the pharynx are pulled upward by the contraction of the stylopharyngeus,the salpingopharyngeus, the thyrohyoid, and the palatopharyngeus muscles.

Answer 686

E) Reason Later in development, secondary (or late) centers of ossification form separately through a process of cartilage hypertrophy, ingrowth of vessels from outside the cartilage template, and replacement of cartilage by new trabecular bone and marrow. This takes place at the ends (epiphyses) of long bones.

Answer 687

A) Reason Sarcoidosis Characterized by immune-mediated, widespread noncaseating granulomas containing T-cells and elevated serum ACE levels. Common in black females. Often asymptomatic except for enlarged lymph nodes.

Answer 688

A) Reason Rapidly adapting, or phasic, receptors (pacinian corpuscle; light touch)■ show a decline in action potential frequency with time in response to a constant stimulus.■ primarily detect onset and offset of a stimulus.

Answer 689

E) Reason chorda tympani nerve: it supplies the mucous membrane of the anterior two thirds of the tongue and the floor of the mouth. It also gives off preganglionic parasympatheticsecretomotor fibers to the submandibular ganglion

Answer 690

E) Reason P. vivaxand P. ovale produce a latent form (hypnozoite) in the liver; this form is the causeof relapses seen with vivax and ovale malaria.

Answer 691

A) Reason The compensatory responses to acute blood loss are as follows: First of all vasoconstriction followed by A decrease in blood volume produces a decrease in venous return. As a result, there is a decrease in both cardiac output and arterial pressure

Answer 692

E) Reason Progressive lengthening of the PR interval until a beat is “dropped” so that ventricular rate is less than that of atria (a P wave not followed by a QRS complex).

Answer 693

A) Reason ■ In chronic respiratory alkalosis, renal compensation (decreased HCO3− reabsorption) has occurred. Thus, arterial pH is decreased toward normal (i.e., a compensation). Symptoms of hypocalcemia (e.g., tingling, numbness, muscle spasms) may occur because H+ and Ca2+ compete for binding sites on plasma proteins. So, plasma H concentration remains almost unchanged.

Answer 694

B) Reason P. malariae infects onlymature red cells; therefore, they produce much lower levels of parasites in theblood and these have the longest incubation period of than other Plasmodium species.

Answer 695

D) Reason Function of Dorsal column-medial lemniscal system is to carryDiscriminative touch, conscious proprioception, vibration, pressure

Answer 696

A) Reason Decreased pressure on carotid sinus decreased stretch leads to decreased afferent baroreceptor firing that leads to decreased AV node refractory period and ultimately increases HR.

Answer 697

C) Reason β-thalassemia major (homozygote):β chain is absent causing severe anemia requiring blood transfusion (2° hemochromatosis).Marrow expansion (“crew cut” on skull x-ray) skeletal deformities. “Chipmunk” facies. Extramedullary hematopoiesis (leads to hepatosplenomegaly).

Answer 698

E) Reason Renin–angiotensin–aldosterone system■ is a slow, hormonal mechanism.■ is used in long-term blood pressure regulation by adjustment of blood volume by increasing Aldosterone and hence plasma volume.■ Renin is an enzyme.■ Angiotensin I is inactive.■ Angiotensin II is physiologically active.

Answer 699

A) Reason When the results of a test are same repeatedly, the confidence of the professional and reliability of the test increases.

Answer 700

D) Reason Landmark dermatomes C2—posterior half of a skull “cap.”C3—high turtleneck shirt.C4—low-collar shirt. C5--Deltoid, C6-- lateral side of wrist

Answer 701

E) Reason Hippocampus: Bilateral lesions lead to inability to consolidate short-term to long-term memory.

Answer 702

B) Reason Root of the clitoris is attached to the undersurface of the urogenital diaphragm and is covered by the bulbospongiosus muscles. It the same muscle that is cut in mediolateral episiotomy.

Answer 703

E) Reason In order to have better results and least complications, it is an important aspect to fulfill the best level of professional competence.

Answer 704

A) Reason The epithelial lining of the airway is composed of ciliated cells (goblet and basal cells are absent in the terminal bronchioles) and an additional type called the Clara cell.

Answer 705

A) Reason Findings: jaundice (Hyperbilirubinemia), tender hepatomegaly, ascites (portal hypertension) , and anorexia. Spreads hematogenously.Diagnosis: inc. α-fetoprotein; ultrasound or contrast CT.

Answer 706

C) Reason Lung stretch receptors:■ are located in the smooth muscle of the airways.■ When these receptors are stimulated by differential concentration of alveolar O2 and K and distention of the lungs, they produce a reflex decrease in breathing frequency (Hering–Breuer reflex).

Answer 707

E) Reason Tumor markers should not be used as the 1° tool for cancer diagnosis in blood. They may be used to monitor tumor recurrence and response to therapy, but definitive diagnosis can be made only via biopsy.

Answer 708

B) Reason Mucor and Rhizopus spp:Mucormycosis. Disease mostly in ketoacidotic diabetic and leukemic patients. Fungi proliferate in blood vessel walls when there is excess ketone and glucose, penetrate cribriform plate, and enter brain. Rhinocerebral,assocaited with frontal lobe abscesses. Headache, facial pain, black necrotic eschar on face; may have cranial nerve involvement.Treatment: amphotericin B.

Answer 709

C) Reason AcetazolamideMECHANISM Carbonic anhydrase inhibitor. Causes self limited NaHCO3 diuresis and dec. total-body HCO3- stores.

Answer 710

B) Reason Coarctation of the aorta:Associated with bicuspid aortic valve.Infantile type: Aorta narrowing is proximal to insertion of ductus arteriosus (preductal). Associated with Turner syndrome. Can present with closure of the ductus arteriosus (reverse with PGE2).

Answer 711

B) Reason Clinical features CAH include:I. Salt wasting with hyponatremia, hyperkalemia, and hypovolemia due to lack of aldosterone. 2. Life-threatening hypotension due to lack of cortisol. 3. Clitoral enlargement (females) or precocious puberty (males) due to excess androgens

Answer 712

C) Reason The white matter of the cerebral hemisphere are of three types:1.commissural fibers(The commissural fibers interconnect the corresponding regions of the two cerebral hemispheres eg Corpus callosum).2.association fibers(These fibers connect the various cortical regions of a cerebral hemisphere eg short and long association fibers).3.projection fibers(These fibers connect the cerebral cortex with lower part of the brain or brainstem and the spinal cord, in both directions eg Internal capsule).

Answer 713

C) Reason PDGF Secreted by activated platelets and macrophages Induces vascular remodeling and smooth muscle cell migration Stimulates fibroblast growth for collagen synthesis

Answer 714

C) Reason The muscle is covered superficially by skin, fascia, the platysma muscle, and the external jugular vein. It is the common site of compression of external jugular vein.

Answer 715

D) Reason FUNCTION: Stimulates linear growth (activating osteoblasts)and muscle mass through IGF-1/somatomedin secretion. inc. insulin resistance (diabetogenic)

Answer 716

A) Reason STERNOCLEIDOMASTOID MUSCLEWhen the sternocleidomastoid muscle contracts,it appears as an oblique band crossing the side of the neckfrom the sternoclavicular joint to the mastoid process of theskull. Its main function is to move the head to opposite side.

Answer 717

A) Reason Here in this scenario when dorsalis pedis artery absent, the perforating branch of the peroneal artery (acessary peroneal artery) will supply the foot.

Answer 718

A) Reason LYMPH DRAINAGEThe upper half of the anal canal drains into the pararectalnodes and then into the inferior mesenteric nodes. Thelower half including the labia majora drain into the medial group of superficial inguinal nodes.

Answer 719

A) Reason UretersThe two ureters are muscular tubes that extend from the kidneys to the posterior surface of the urinary bladd. Each ureter measures approximately 10 inch (25 cm) inlength and has an upper expanded end called the renalpelvis.

Answer 720

C) Reason • Subarachnoid space lies between the arachnoid and pia mater containing CSF: contains blood vessels; site of subarachnoid hemorrhage.

Answer 721

B) Reason In damage of superficial branch of radial nerve there is sensory loss as well, but in case of deep nerve damaged, there is motor loss only.

Answer 722

A) Reason Ankle jerk has the root value of S1. Moreover Lumbosacral pain is associated with spine injury mostly. Ankle jerk lost mean lesion at S1.

Answer 723

B) Reason Peroxisome Membrane-enclosed organelle involved in catabolism of very-long-chain fatty acids, branched-chain fatty acids, and amino acids.

Answer 724

E) Reason Eversion: (opposite movement of the foot so that the solefaces laterally): caused by peroneus longus, peroneus brevis, peroneus tertius, and lateral tendons of extensor digitorumlongus muscles. It is lost in lesions of common peroneal nerve.

Answer 725

B) Reason Uterine Artery thenpasses above the lateral fornix of vagina just close to the ureter to reach theuterus, where it ascends between the layers of the broadligament along the lateral margin of the uterus. It ends byfollowing the uterine tube laterally, where it anastomoseswith the ovarian artery.

Answer 726

B) Reason Hemoglobin Hemoglobin (Hb) is composed of 4 polypeptide subunits (2 α and 2 β) and exists in 2 forms:T (taut) form has low affinity for O2.R (relaxed) form has high affinity for O2

Answer 727

E) Reason Aortic aneurysms: Localized pathologic dilation of the aorta. Presents with pulsating mass most commonly over T10 level. May cause pain, which is a sign of leaking, dissection, or imminent rupture.

Answer 728

B) Reason Retinoblastoma is a malignant retinal tumor of childhood. 1. The tumor is sporadic in approximately 60% of cases; sporadic cases are unilateral and mono centric in origin. 2. It is familial in approximately 40% of cases; familial cases are frequently bilateral and multicentric in origin. It involves the Optic nerve and spread through it to the extraocular tissues.

Answer 729

D) Reason MENINGIOMA A. Benign tumor of arachnoid cells, most of the time associated with radiation exposure.B. Most common benign CNS tumor in adults More commonly seen in women; rare in children C. May present as seizures; tumor compresses, but does not invade, the cortex. D. Imaging reveals a round mass attached to the dura.

Answer 730

C) Reason Wilms tumor (nephroblastoma) is the most common renal malignancy of early childhood (ages 2–4). Contains embryonic glomerular structures. Presents with huge, palpable flank mass and/or hematuria.

Answer 731

D) Reason 1b fibers inervate golgi tendon organ (GTO), While 1a fibers inervate the muscle spindles.

Answer 732

D) Reason Non Hemolytic febrile reaction is just a febrile manifestation and is most of the time self remitting condition, can be managed by antipyretics.

Answer 733

D) Reason Ergotamine causes severe vasoconstriction of the periphral vasculature leading to adverse complications.

Answer 734

D) Reason Hemolytic uremic syndrome, causes bloody diarrhea and hemolytic manifestations of petechiai, which typically is associated with enterohemorrhagic Escherichia coli (EHEC), also may occur after infection with shigellae that secrete Shiga toxin.

Answer 735

A) Reason Entamoeba histolytica:Amebiasis: bloody diarrhea (dysentery), usually involves cecum, liver abscess (“anchovy paste” exudate), RUQ pain (histology shows flask-shaped ulcer if submucosal abscess of colon ruptures)

Answer 736

C) Reason • The indifferent gonad begins development in a column of intermediate mesoderm called the urogenital ridge during week 4, and develops into the genitourinary system.

Answer 737

E) Reason The ischiorectal fossa is a wedge-shaped space on each sideof the anal canal. The base of the wedge is superficial and is formed by the skin. The edge of the wedge is formed by the junction of the medial and the lateral walls.The medial wall is formed by the sloping levator ani muscle, external anal sphincter and the anal canal.

Answer 738

D) Reason The lesser sac lies behind the stomach and the lesseromentum. It extends upward as far as the diaphragm and downward between the layers of the greater omentum

Answer 739

D) Reason Not a single features given in scenario is suggestive of Myelodysplastic disorders (pancytopenia with blast cells and ring sideroblasts), so most probable diagnosis js the Aplastic anemic.

Answer 740

C) Reason Submandibular gland is mixed, and Parotid is pure serous while Sublingual is pure mucous.

Answer 741

E) Reason Large intestinal motility:■ Fecal material moves from the cecum to the colon (i.e., through the ascending, transverse, descending, and sigmoid colons), to the rectum, and then to the anal canal. Water and electrolytes are absorbed from colon.

Answer 742

D) Reason Pigment-producing bacteria:Actinomyces israelii—yellow “sulfur” granules, which are composed of filaments of bacteria.Israel has yellow sand.S. aureus—yellow pigment. aureus (Latin) = gold.Pseudomonas aeruginosa—blue-green pigment. Aerugula is green.Serratia marcescens—red pigment. Serratia marcescens—think red maraschinocherries.

Answer 743

B) Reason β-thalassemia minor (heterozygote):β chain is underproduced.Usually asymptomatic.Diagnosis confirmed by inc. HbA2 (> 3.5%) on electrophoresis. Prenatal diagnosis by Chorionic Villous sampling (CVS).

Answer 744

A) Reason Lymphatic Drainage:The lateral quadrants of the breast drain into the anterior axillary or the pectoral node. The medial quadrantsdrain into the internal thoracic nodes. A few lymph vesselsalso drain posteriorly into the posterior intercostal nodes,and some communicate with the lymphatic vessels of theopposite breast and with those of the anterior abdominalwall.

Answer 745

A) Reason Lymphatic Drainage:The lateral quadrants of the breast drain into the anterior axillary or the pectoral node. The medial quadrantsdrain into the internal thoracic nodes. A few lymph vesselsalso drain posteriorly into the posterior intercostal nodes,and some communicate with the lymphatic vessels of theopposite breast and with those of the anterior abdominalwall.

Answer 746

D) Reason Adrenal cortex (derived from mesoderm) and medulla (derived from neural crest)

Answer 747

E) Reason Shock occasionally results without any loss of bloodvolume. Instead, the vascular capacity increases somuch that even the normal amount of blood becomesincapable of filling the circulatory system adequately.One of the major causes of this is sudden loss of vasomotor tone throughout the body, resulting especially inmassive dilation of the veins. The resulting conditionis known as neurogenic shock.

Answer 748

D) Reason Blood group A is one which contains antigen A on Red blood cells and antibodies B in serum.

Answer 749

D) Reason Acute marginal artery—A branch of RCA: supplies right ventricle and hence the base of the heart. Its occlusion can lead to infarction of the base of the heart.

Answer 750

B) Reason Nerve Supply Pudendal nerve, Function: Supports the pelvic viscera;sphincter to the anorectal junction and vagina

Answer 751

E) Reason The lymph drains into the internal iliac nodes.Nerve SupplyInferior hypogastric plexuses supply the prostate.

Answer 752

B) Reason Layers of the anterior abdominal wall from outer to inside are:1. Skin 2. Superficial fascia a. Camper (fatty) b. Scarpa (fibrous) 3. External oblique 4. I nternal oblique 5. Transversus abdominis 6. Transversalis fascia 7. Extra peritoneal 8. Parietal peritoneum

Answer 753

E) Reason Corynebacterium diphtheriae:Produces exotoxinInactivate elongation factor (EF-2)Manifestations: Pharyngitis with pseudomembranes in throat and severe lymphadenopathy (bull neck).

Answer 754

A) Reason Hemophilia A or B — Intrinsic pathway coagulation defect but bleeding time is normal A: deficiency of factor VIII, inc. PTT.B: deficiency of factor IX, inc. PTT.Macrohemorrhage in hemophilia—hemarthroses (bleeding into joints), easy bruising, inc. PTT. Treatment: recombinant factor VIII (in hemophilia A).

Answer 755

E) Reason tRNA Structure: 75–90 nucleotides, 2º structure, cloverleaf form, anticodon end is opposite 3′ aminoacyl end. All tRNAs, both eukaryotic and prokaryotic, have CCA at 3′ end along with a high percentage of chemically modified bases.

Answer 756

D) Reason Deepest non-REM sleep (slow-wave sleep); when sleepwalking, night terrors, and bedwetting occur.Delta (lowest frequency, highest amplitude) is the charecteristic wave of deep sleep.

Answer 757

E) Reason Popliteal Lymph NodesSituated in the popliteal fossa, the popliteal lymph nodes receive the superficial lymph vessels that accompany thesmall saphenous vein from the lateral side of the foot andfrom the back and the lateral side of the calf. They also receive lymph from the deep structures from lateral side of foot.

Answer 758

D) Reason Saphnous nerve is the continuation of the femoral nerve, and supplies the medial side of foot and ball of big toe.

Answer 759

E) Reason Infraclavicular (deltopectoral) nodes are not strictlyaxillary nodes, because they are located outside the axilla.They lie in the interval between the deltoid and the pectoralis major muscles. They receive lymph from the superficial vessels of the lateral side (thumb) of the hand, the forearm, and the arm; the lymph vessels accompany thecephalic vein.

Answer 760

A) Reason Lymph Drainageof The Ovaries:The lymph drains into the para-aortic nodes at the level ofthe first lumbar vertebra.

Answer 761

C) Reason Referral system is established to provide the better management to the patient from a center with less facilitates to the one with better facilitates.

Answer 762

C) Reason Large vessel complications of DM: atherosclerosis, CAD, peripheral vascular occlusive disease, and gangrene causing limb loss, cerebrovascular disease. MI most common cause of death.

Answer 763

E) Reason Parasympathetic effects on heart rate and conduction velocity■ The SA node, atria, and AV node have parasympathetic vagal innervation, but the ventricles do not. The neurotransmitter is acetylcholine (ACh), which acts at muscarinic receptors.

Answer 764

E) Reason According to the standard ATLS protocol for the accident and emergency management, ABCDE is followed, while in an hypotensive bleeding pt. IV fluids are the 1st management in ATLS protocol.

Answer 765

A) Reason FUNCTION: inc. Blood pressure (upregulates α1-receptors on arterioles dec. sensitivity to norepinephrine and epinephrineInc. Insulin resistance (diabetogenic)Inc. Gluconeogenesis, lipolysis, and proteolysisDec. Fibroblast activity (causes striae) Dec. Inflammatory and Immune responses, infalmatory and wound contraction.

Answer 766

B) Reason Right-dominant circulation = 85% = PDA arises from RCA.Left-dominant circulation = 8% = PDA arises from LCX.Codominant circulation = 7% = PDA arises from both LCX and RCA

Answer 767

E) Reason Neurons are one of the example of the permanent tissues that don"t regenerate usually. Neurons are the cells that bears least anoxia.

Answer 768

B) Reason Epidural anesthesia can often cause injury to the lower spinal nerves that often cause its manifestations most common of which is the atonic bladder or the urinary retention.

Answer 769

A) Reason As glucose transport is an example of the facilitated transport, that is why its transport increases by increasing the carrier proteins (GLUT).

Answer 770

A) Reason Lobar Pneumonia: Causative organisms are S. pneumoniae most frequently, also Legionella, KlebsiellaFindings: Intra-alveolar exudate leading to consolidation; may involve entire lung.

Answer 771

C) Reason URETERIC CONSTRICTIONS AND STONESUreteric stones may be arrested at the following sites:• Where the renal pelvis joins the ureter.• Where the ureter is kinked as it crosses the pelvicbrim along the bifurcation of common iliac artry to enter the pelvis.• Where the ureter pierces the bladder wall.

Answer 772

B) Reason Prostaglandins■ Prostacyclin is a vasodilator in several vascular beds and it inhibits the formation of thrombus.■ E-series prostaglandins are vasodilators.

Answer 773

D) Reason In our country, being a Muslim state, there is less cases with alcoholic cirrhosis. But due to the overuse of contaminated objects, cases of hep. C are more common.

Answer 774

E) Reason Myelination increases conduction velocity of signals transmitted down axons. Results in saltatory conduction of action potential between nodes of Ranvier, where there are high concentrations of Na+channels. CNS—oligodendrocytes; PNS—Schwann cells

Answer 775

A) Reason Acute kidney injury(acute renal failure)In normal nephron, BUN is reabsorbed (for countercurrent multiplication), but creatinine is not. Presentation can be azotemia or commatose state.

Answer 776

C) Reason The deep inguinal ring is an oval opening in the fascia transversalis and lies approximately 0.5 in. (1.3 cm)

Answer 777

B) Reason Completeoxidation of glucose through glycolysis pluscitric acid cycle will yield a net 38 ATPs .

Answer 778

D) Reason Barrett esophagus Glandular metaplasia—replacement of nonkeratinized (stratified) squamous epithelium with intestinal epithelium (nonciliated columnar with goblets cells) in the distal esophagus. Due to chronic acid reflux (GERD)

Answer 779

B) Reason Intervertebral disc forms secondary cartilaginous joint between the bodies of the vertebrae. If the nucleus pulposus part of the disc gets protruded backwards, it may press on the spinal nerve leaving out from the intervertebral foramina. The condition is known as herniation of the disc

Answer 780

E) Reason The part covering the conceptus is the decidua capsularis; that betweenthe conceptus and the uterine muscular wall is the decidua basalis (where the placenta subsequentlydevelops); and that which lines the remainder of the body of the uterus is the decidua parietalis. Uterus is obiliterated by these 2 decidua.

Answer 781

C) Reason Horner syndrome Sympathectomy of face:Ptosis (slight drooping of eyelid: superior tarsal muscle)Anhydrosis (absence of sweating) and flushing (rubor) of affected side of faceMiosis (pupil constriction)Associated with lesion of spinal cord above T1

Answer 782

B) Reason Anterolateral (spinothalamic tract) system:The anterolateral system carries pain, temperature, and crude touch sensations from the extremities and trunk.

Answer 783

D) Reason Cataract:Painless, often bilateral, opacification of lens dec. in vision. Risk factors: incresing age, smoking, EtOH, excessive sunlight, drugs (prolonged corticosteroid use, chloroquin) classic galactosemia, galactokinase deficiency, diabetes (sorbitol), trauma, infection.

Answer 784

E) Reason Mood disorder is characterized by an abnormal range of moods or internal emotional states and loss of control over them. Caused by imbalance of Dopamine, neurotransmitter for mood.Severity of moods causes distress and impairment in social and occupational functioning.

Answer 785

C) Reason Contralateral hemiparesis—upper and lower limbs.sec. contralateral proprioception. Ipsilateral hypoglossal dysfunction (tongue deviates ipsilaterally).Stroke commonly bilateral.Medial medullary syndrome— caused by infarct of paramedian branches of ASA and vertebral arteries

Answer 786

E) Reason Stress hormones are those that are secreted in in stressful conditions. These include ACTH, GH, Cortisol, epinephrine, Norepinephrine and glucagon.

Answer 787

D) Reason Small cell (oat cell) carcinoma:Central location, Undifferentiated and very aggressive.May produce ACTH (Cushing syndromeg) , ADH, or Antibodies against presynaptic Ca2+ channels (Lambert-Eaton myasthenic syndrome).

Answer 788

B) Reason Whenever there is an injury that would stimulate the endothelium, then vasoconstriction is the 1st response for the Hemostasis.

Answer 789

B) Reason Whenever there is a fluid in the the pleural cavity, the percussion note will be dull,normal note is tympanic in presence of normal pleural cavity.

Answer 790

E) Reason There will be increase in ICF.

Answer 791

E) Reason increase oncotic pressure is most correct option here.

Answer 792

C) Reason The cephalic vein can be seen in the proximal roof of the snuffbox, and the pulsation of the radial arterycan be felt in its depth. The snuffbox is bounded on the radial side by the tendons of abductor pollicislongus laterally and extensor pollicis brevis medially; these tendons lie close to each other

Answer 793

B) Reason Dysplasia and carcinoma in situDisordered epithelial growth; begins at basal layer of squamocolumnar junction (transition zone) and extends outward. Classified as CIN 1, CIN 2, or CIN 3 (severe dysplasia or carcinoma in situ), depending on extent of dysplasia. Associated with HPV 16 and HPV 18, which produce both the E6 gene product (inhibits p53 suppressor gene) and E7 gene product (inhibits RB suppressor gene).

Answer 794

A) Reason Tumor suppressors: p53 and hypophosphorylated Rb normally inhibit G1-to-S progression; mutations in these genes result in unrestrained cell division and increased cell survival(e.g., Li-Fraumani syndrome).

Answer 795

A) Reason Three terminal arteries: two common iliac arteries and themedian sacral artery. Two are the continuation and third originates from posterior of the bifurcation of aorta

Answer 796

D) Reason Renin Secreted by JG cells in response to inc. renal arterial pressure and inc. renal sympathetic discharge (β1 effect).

Answer 797

D) Reason Measurement of renal plasma flow (RPF)—by clearance of para-aminohippuric acid (PAH)■ PAH is filtered and secreted by the renal tubules.■ Clearance of PAH is used to measure RPF.■ Clearance of PAH measures effective RPF and underestimates true RPF by 10%.

Answer 798

E) Reason Intracellular fluid (ICF)■ is two-thirds of TBW.■ The major cations of ICF are K+ and Mg2+.■ The major anions of ICF are protein and organic phosphates

Answer 799

B) Reason Kwashiorkor:Protein malnutrition resulting in skin lesions, edema, liver malfunction (fatty change due to decreased apolipoprotein synthesis). Clinical picture is small child with swollen belly

Answer 800

A) Reason The preganglionic cell bodies of the parasympathetic nervous system are found in the CNS in one of 2 places: • Gray matter of brain stem associated with cranial nerves III, VII, IX, and X, or • Spinal cord gray in sacral segments S2 3, and 4 (pelvic splanchnics)

Answer 801

C) Reason Anabolic effects of insulin:inc. glucose transport in skeletal muscle and adipose tissueinc. glycogen synthesis and storageinc. triglyceride synthesisinc. Na+ retention (kidneys)

Answer 802

D) Reason Within each lobule are 1 -4 tubes, seminiferous tubules (developed under the action of FSH and androgen), where spermatozoa are produced. Each tubule is a coiled, non-branching closed loop that is 1 50-200 µm in diameter and 30-70 cm in length.

Answer 803

A) Reason Enzymes are the specific type of the functional proteins that speed up the reaction by decreasing the acitivation energy.

Answer 804

B) Reason REGULATION Prolactin secretion from anterior pituitary is tonically inhibited by dopamine from hypothalamus. Prolactin in turn inhibits its own secretion by dec. dopamine synthesis and secretion from hypothalamus. TRH inc.prolactin secretion.

Answer 805

E) Reason The “blip” in the aortic pressure tracing occurs during aortic cystole after closure of the aortic valve and is called the dicrotic notch, or incisura.

Answer 806

A) Reason Surfactant deficiency inc. surface tension decreases lung compliance and increased chances of alveolar collapse. A lecithin:sphingomyelin ratio < 1.5 in amniotic fluid is predictive of neonatal respiratory distress syndrome.

Answer 807

C) Reason Granuloma: nodular collections of epithelioidmacrophages (derived from monocytes) and giant cells. Outcomes include scarring and amyloidosis.

Answer 808

D) Reason Small vessel disease (diffuse thickening of basement membrane) retinopathy (hemorrhage, exudates, microaneurysms, vessel proliferation) , glaucoma, nephropathy (nodular sclerosis, progressive proteinuria, chronic renal failure, arteriolosclerosis leading to hypertension, Kimmelstiel-Wilson nodules)

Answer 809

A) Reason Natural killer cells Use perforin and granzymes to induce apoptosis of virally infected cells and tumor cells.Activity enhanced by IL-2, IL-12, IFN-β, and IFN-α.

Answer 810

D) Reason Measurement of GFR—clearance of inulin■ Inulin is filtered, but not reabsorbed or secreted by the renal tubules.■ The clearance of inulin is used to measure GFR

Answer 811

E) Reason liquids don"t have any physical hinderence to the swallowing, if there is Neuromuscular disorders that cause dysphagia to liquids as well.

Answer 812

B) Reason The urethra extends from the urinary bladder to the tip of the penis. The prostatic urethra is composed of transitional epithelium or Urothelium and the distal urethra of stratified epithelium. It has no basement membrane.

Answer 813

B) Reason Medullary carcinoma From parafollicular “C cells”; produces calcitonin, sheets of cells in an amyloid stroma B. Associated with MEN 2A (especially phaeochromocytoma) and 2B (RET mutations).

Answer 814

D) Reason Candida albicans: alba = white.Systemic or superficial fungal infection. Oral and esophageal thrush in immunocompromised (neonates, steroids, pregnancy especially 3rd trimester, diabetes, AIDS), vulvovaginitis (diabetes, use of antibiotics), diaper rash, endocarditis in IV drug users, disseminated candidiasis (to any organ), chronic mucocutaneous candidiasis.

Answer 815

C) Reason Face is supplied by the Trigeminal nerve. Upper 3rd of face is supplied by the Ophthalmic nerve, middle by Maxillary nerve, and lower 3rd by the mandibular division of Trigeminal nerve.

Answer 816

E) Reason CLINICAL USE: Minor surgical procedures especially procain, spinal anesthesia. If allergic to esters, give amides.TOXICITY:CNS excitation, severe cardiovascular toxicity (bupivacaine), hypertension, hypotension, and arrhythmias (cocaine).

Answer 817

B) Reason When APC gene is detected. the colon will be at risk of tumor formation. Further when K-RAS is mutated, there is risk of adenoma (as in this scenario) and finally p53 mutation causes cancer (molecular progression)

Answer 818

C) Reason Forced ExpirationForced expiration is an active process accomplished bycontraction of the muscles of the anterior abdominal wall i.e. the transversus abdominis(forcing the relaxed diaphragm upward by raising intraabdominal pressure) and contraction of the quadratuslumborum (pulling the twelfth rib downward).

Answer 819

C) Reason Stylomandibular Ligament:The stylomandibular ligament is the main support of the TM joint, it is attached to the styloid process above and to the angle of the mandible below.

Answer 820

E) Reason Malignant Melanoma: Common tumor with significant risk of metastasis. S-100 tumor marker and NK cells on histology. Associated with sunlight exposure; fair-skinned persons are at risk. Depth of tumor correlates with risk of metastasis.

Answer 821

C) Reason Basophils: Mediates allergic reaction. Densely (dark)basophilic granules A containing heparin (anticoagulant), histamine (vasodilator), and leukotrienes.

Answer 822

A) Reason MOVEMENTThe hip joint has a wide range of movement.• Flexion: Iliopsoas, rectus femoris (strongest of flexors), sartorius, and adductormuscles.• Extension (posterior movement of the flexed thigh):Gluteus maximus and hamstring muscles

Answer 823

A) Reason Plantar flexion: (toes pointing downward): affected by tibial nerve lesion. Muscle causing movements are Gastrocnemius, soleus, plantaris, peroneus longus, peroneus brevis,tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles.

Answer 824

E) Reason The trigeminal nerve is the largest cranial nerve .It leaves the anterior aspect of the pons as a small motor rootand a large sensory root, and it passes forward, out of theposterior cranial fossa, to reach the middle cranial fossa, where it gives meningeal branches to its dura.

Answer 825

D) Reason Factor X Stuart factor; Stuart-Prower factorFactor XI Plasma thromboplastin antecedent (PTA); antihemophilic factor CFactor XII Hageman factorFactor XIII Fibrin-stabilizing factorPrekallikrein Fletcher factor

Answer 826

E) Reason P. falciparum—severe; irregular and high gradefever patterns; parasitized RBCs occlude capillaries in brain (cerebral malaria), kidneys, lungs.

Answer 827

C) Reason Chaperone protein: Intracellular protein involved in facilitating and/or maintaining protein folding. In yeast, some are heat shock proteins (e.g., Hsp60) that are expressed at high temperatures to prevent protein denaturing/misfolding

Answer 828

D) Reason ■ Thick ascending limb of loop of Henle is impermeable to water. Thus, NaCl is reabsorbed without water. As a result, tubular fluid [Na+] and tubular fluid osmolarity decrease to less than their concentrations in plasma (i.e., TF/PNa+ and TF/Posm < 1.0). This segment, therefore, is called the diluting segment.

Answer 829

D) Reason The TCA cycle produces 3 NADH, 1 FADH2, 2 CO2, 1 GTP per acetyl-CoA = 10 ATP/acetyl-CoA (2× everything per glucose). TCA cycle reactions occur in the mitochondria.α-ketoglutarate dehydrogenase complex requires the same cofactors as the pyruvate dehydrogenase complex (B1, B2, B3, B5, lipoic acid).

Answer 830

C) Reason Treatment: topical azole for vaginal; fluconazole or caspofungin for oral/esophageal; fluconazole, amphotericin B, or caspofungin for systemic.

Answer 831

D) Reason It has a completeperitoneal covering, which is attached to the mesentery ofthe small intestine by a short mesentery of its own called the mesoappendix. The mesoappendix contains the appendicular vessels and nerves.

Answer 832

E) Reason The afferent impulses enter the second, third, and fourthsacral segments of the spinal cord, these control the bladder tone.Efferent impulses leavethe cord from the same segments and pass via the parasympathetic preganglionic nerve fibers in the hypogastricplexuses to the bladder wall, where they synapse with postganglionic neurons.

Answer 833

C) Reason Crocodile tears (gustatory lacrimation). There is unil ateral lacrimation with mastication. This is due to faulty regeneration of parasympathetic fibres of facial nerve which now supply lacrimal gland instead of the salivary glands.

Answer 834

D) Reason It spares during injury of little finger.

Answer 835

A) Reason Any substance that deionizes the blood calcium willprevent coagulation.The negatively charged citrate ionis especially valuable for this purpose, mixed withblood usually in the form of sodium, ammonium, orpotassium citrate (CPDA). The citrate ion combines withcalcium in the blood to cause an un-ionized calciumcompound, and the lack of ionic calcium preventscoagulation

Answer 836

C) Reason Giemsa:stains Chlamydia, Borrelia, Rickettsiae, Trypanosomes, Plasmodium.

Answer 837

B) Reason Saphenous nerve, which descends through thefemoral triangle and the adductor canal and crosses thefemoral artery. The nerve emerges on the medial side ofthe knee joint between the tendons of the sartorius and thegracilis muscles, and it accompanies the great saphenousvein down the medial side of the leg and in front of the medial malleolus. It passes along the medial border of thefoot as far as the ball of the big toe. It is the commonally injured nerve in venopunture of children.

Answer 838

A) Reason The ischiorectal fossa and the ischial spines can bepalpated laterally in the pelvis, Ischial spine palpated here is the station for fetus descent in labour

Answer 839

A) Reason FINDINGS of Cushing syndrome: Hypertension due to hyperosmolar over hydration leading to inv. volume), weight gain, moon facies, truncal obesity B, buffalo hump, hyperglycemia (insulin resistance), skin changes (thinning, striae), osteoporosis, amenorrhea, and immune suppression.

Answer 840

E) Reason AcetazolamideMECHANISM Carbonic anhydrase inhibitor. Causes self limited NaHCO3 diuresis and dec. total-body HCO3- stores.

Answer 841

C) Reason TRANSVERSE COLONThe transverse colon is approximately 15 in. (38 cm) inlength and passes across the abdomen, occupying the umbilical and the hypogastric region. It begins atthe right colic flexure below the right lobe of the liver andhangs downward, suspended by the transverse mesocolonfrom the pancreas. It then ascends from anterior to the dudenum to the left colic flexurebelow the spleen.

Answer 842

D) Reason In pregnancy, anterior pituitary hormones including MSH are increased. In 3rd trimester, these excessive melanocytes come under the eidermis and are reason for the increased pigmentation during pregnancy.

Answer 843

E) Reason The macula densa is formed by tall cuboidal cells with deep basal lamina in the wall of the DCT which detect sodium levels in the tubular fluid.

Answer 844

A) Reason The inner cell mass of the first week differentiates into the epiblast and hypoblast cells and forms a bilaminar embryonic disk. An amniotic cavity develops from the epiblast and the primary yolk sac replaces the blastocyst cavity. Hypoblast then forms the embrionic coelom.

Answer 845

A) Reason Giant cell tumor:20–40 years old.Epiphyseal end of long bones.Locally aggressive benign tumor often around knee.“Soap bubble” appearance on x-ray.Has multinucleated giant cells.

Answer 846

E) Reason Carcinomas have keratin in their structure. First step in the invasion of malignant cells through an epithelium results from a loss of expression of cadherins that weakens the epithelium.

Answer 847

D) Reason BRONCHOPULMONARY SEGMENTSBronchopulmonary segments are the anatomic, functional,and surgical units of the lungs. Each lobar (secondary)bronchus, which passes to a lobe of the lung, gives offbranches called segmental (tertiary) bronchi .

Answer 848

D) Reason Candida albicans: alba = white.Systemic or superficial fungal infection. Oral and esophageal thrush in immunocompromised (neonates, Burns , steroids, diabetes, AIDS), vulvovaginitis (diabetes, use of antibiotics), diaper rash, endocarditis in IV drug users, disseminated candidiasis (to any organ), chronic mucocutaneous candidiasis.

Answer 849

B) Reason Oblique Popliteal LigamentThe oblique popliteal ligament is a tendinous expansion ofthe semimembranosus muscle. It strengthens the backof the capsule.

Answer 850

A) Reason • Flexion: Lumbricals and interossei muscles, assisted byflexor digitorum superficialis and profundus muscles.• Extension: Extensor digitorum, extensor indicis, and extensor digiti minimi muscles.

Answer 851

E) Reason Early proximal convoluted tubule (PCT)—contains brush border. Reabsorbs all of the glucose and amino acids and most of the HCO3–, Na+, Cl–, PO43–, K+, and H2O. Isotonic absorption. Generates and secretes NH3, which acts as a buffer for secreted H+.

Answer 852

E) Reason meduloblastoma are most radiosensitive tumors and glioblastoma are least radiosensitive.

Answer 853

D) Reason Prostatic adenocarcinoma:Common in men > 50 years old. Arises most often from the posterior lobe (peripheral zone) of the prostate gland and is most frequently diagnosed by inc. PSA and subsequent needle core biopsies. Prostatic acid phosphatase (PAP) and PSA are useful tumor markers (inc. total PSA, with inc. fraction of free PSA).

Answer 854

C) Reason SEMINAL VESICLESThe seminal vesicles are paired organs that lie on the posterior surface of the bladder and lateral to the terminal part of the vas deferens.

Answer 855

E) Reason Secondary Hyperparathyroidism: 2° hyperplasia due to decreased gut Ca2+ absorption and increased PO43-, most often in chronic renal disease (causes hypovitaminosis D decreased Ca2+ absorption).

Answer 856

B) Reason Cyclosporine: MoA, Calcineurin inhibitor; binds cyclophilin. Blocks T cell activation by preventing IL-2 transcription.Uses: Transplant rejection prophylaxis, psoriasis, rheumatoid arthritis.

Answer 857

D) Reason Scar formation 70–80% of tensile strength returns at 3 months following wound; little additional tensile strength will be regained. Abnormally thick and tough struture formed by excessive scarring is the Hypertrophic scar.

Answer 858

E) Reason From medial to lateral, the cubital fossa contains the median nerve, the bifurcation of the brachial artery into the ulnar and the radial arteries, the tendon of the biceps muscle,and the radial nerve and its deep branch. Median nerve is the most commonly damaged during venopunture in cubital fossa.

Answer 859

E) Reason Bcl-2 prevents cytochrome c release by binding to and inhibiting Apaf-1. Apaf-1 normally induces the activation of caspases. If Bcl-2 is overexpressed (e.g., follicular lymphoma), then Apaf-1 is overly inhibited, leading to inc. caspase activation and tumorigenesis.

Answer 860

D) Reason Specific gravity of urine is the measurement of the concentration of solutes in urine. As the concentrating ability of the kidney is impaired, the specific gravity changes.

Answer 861

D) Reason Vitamin D D2 = ergocalciferol—ingested from plants.D3 = cholecalciferol—consumed in milk, formed in sun-exposed skin (stratum basale).25-OH D3 = storage form. 1,25-(OH)2 D3 (calcitriol) = active form

Answer 862

D) Reason The pudendal nerve (S2, 3, and 4) leaves the pelvisthrough the greater sciatic foramen and enters the perineum through the lesser sciatic foramen.• Nerves to the piriformis muscle.

Answer 863

B) Reason TOXICITY Iatrogenic Cushing syndrome—buffalo hump, moon facies, truncal obesity, muscle wasting, thin skin, easy bruisability, osteoporosis (treat with bisphosphonates), poor sugrar control in diabetics, adrenocortical atrophy, peptic ulcers, diabetes (if chronic).Adrenal insufficiency when drug stopped abruptly after chronic use.

Answer 864

E) Reason Type II: Autoimmune hemolytic anemiaPernicious anemiaIdiopathic thrombocytopenic purpuraErythroblastosis fetalisAcute hemolytic transfusion reactionsRheumatic feverGoodpasture syndromeBullous pemphigoidPemphigus vulgaris

Answer 865

E) Reason Muscles of the perineum, including the external analsphincter, mucous membrane of the lower half of theanal canal, perianal skin, skin of the penis, scrotum,clitoris, and labia majora and minora (vulva).

Answer 866

D) Reason Ca channel blockers are the Vasodilators that are used along with the volatile anesthetics. Their Vasodilation property is the cause of hypotension.

Answer 867

B) Reason It is clear that wheneither Factor VIII or platelets are in short supply,this step is deficient. Factor VIII is the factor thatis missing in a person who has classic hemophilia (darranged PTT and normal PT),for which reason it is called antihemophilic factor.Platelets are the clotting factor that is lacking inthe bleeding disease called thrombocytopenia

Answer 868

D) Reason Autograft From self.Syngeneic graft From identical twin or clone.Allograft From nonidentical individual of same species.Xenograft From different species.

Answer 869

C) Reason Labs: schistocytes, increased fibrin split products (d-dimers), decreased fibrinogen, decreased factors V and VIII

Answer 870

C) Reason Falciform Ligament Connects Liver to anterior abdominal wallIt contains Ligamentum teres hepatis/ Round ligament(derivative of fetal umbilical vein)

Answer 871

C) Reason Celiac Disease: Autoimmune-mediated intolerance of gliadin (wheat) leading to malabsorption and steatorrhea. Associated with HLA-DQ2, HLA-DQ8, and northern European descent. Findings include anti-endomysial, anti-tissue transglutaminase, and anti-gliadin antibodies; blunting of villi; and lymphocytes in the lamina propria. decreased mucosal absorption that primarily affects distal duodenum and/or proximal jejunum. Jejunal biopsy is the diagnostic evaluation.

Answer 872

B) Reason Ischiorectal FossaThe ischiorectal fossa is a wedge-shaped space on each sideof the anal canal . The base of the wedge is superficial and is formed by the skin. The edge of the wedge isformed by the junction of the medial and the lateral walls.The medial wall and roof is formed by the sloping levator ani muscleand the anal canal; the lateral wall is formed by the lower part of Obturator internus muscle.

Answer 873

B) Reason The citrate ion combines withcalcium in the blood to cause an un-ionized calciumcompound, and the lack of ionic calcium preventscoagulation. Citrate anticoagulants have an importantadvantage over the oxalate anticoagulants becauseoxalate is toxic to the body

Answer 874

A) Reason Lymph DrainageFrom the fundus, the lymph vessels follow the ovarian arteryto the para-aortic nodes at the level of the first lumbar vertebra. From the body and the cervix, the lymph vessels draininto the internal and the external iliac nodes.

Answer 875

B) Reason The right kidney (L3) is slightly lower than the left kidney (L2) because of the large sizeof the right lobe of the liver.

Answer 876

D) Reason CONTENTS OF THE DEEP PERINEAL POUCHIn males, the deep perineal pouch contains the following:• The membranous part of the urethra.• The sphincter urethrae.• The bulbourethral glands.• The deep transverse perineal muscles.• The internal pudendal vessels.• The dorsal nerves of the penis

Answer 877

C) Reason Inversion (movement of the foot so that the sole facesmedially): Tibialis anterior, extensor hallucis longus, medial tendons of extensor digitorum longus, and tibialis posterior muscles.• Eversion (opposite movement of the foot so that the solefaces laterally): Peroneus longus, peroneus brevis, peroneus tertius, and lateral tendons of extensor digitorumlongus muscles.

Answer 878

E) Reason The inner membrane is impermeable to most small ions (Na+, K+, H+) and small molecules (ATP, adenosine diphosphate, pyruvate). The impermeability is likely related to the high content of the lipid cardiolipin

Answer 879

B) Reason Normal anion gap (8−12 mEq/L):HARD-ASS:HyperalimentationAddison diseaseRenal tubular acidosisDiarrheaAcetazolamideSpironolactoneSaline infusion

Answer 880

D) Reason Acute appendicitis is an example of the acute inflammatory process, and cells that mediate an acute inflammation are neutrophils, while lymphocytes mediate the chronic inflamation.

Answer 881

A) Reason BOUNDARIES OF THE EPIPLOIC FORAMEN• Anteriorly: Free border of the lesser omentum, the bileduct, the hepatic artery, and the portal vein.• Posteriorly: Inferior vena cava.• Superiorly: Caudate process of the caudate lobe of theliver.• Inferiorly: First part of the duodenum.

Answer 882

C) Reason Acute pericarditis Commonly presents with sharp pain, aggravated by inspiration, and relieved by sitting up and leaning forward. Presents with friction rub. ECG changes include widespread ST-segment elevation and/or PR depression.

Answer 883

B) Reason TOXICITY Hyperkalemia (can lead to arrhythmias), endocrine effects with spironolactone (e.g., gynecomastia, antiandrogen effects.

Answer 884

D) Reason They are related to an articular or nonarticular bony surface, and the surfaces of contact are covered with hyaline cartilage and lubricated by a bursa or synovial membrane. Examples: patella, pisiform, fabella.

Answer 885

E) Reason It is supplied by muscular branches of ulnar nerve.

Answer 886

B) Reason Associated with Aschoff bodies (granuloma with giant cells [blue arrows in A]), Anitschkow cells (enlarged macrophages with ovoid, wavy, rod-like nucleus, inc. ASO titers.Immune mediated (type II hypersensitivity); not a direct effect of bacteria. Antibodies to M protein cross-react with self antigens.

Answer 887

D) Reason Parasympathetic system is characterized by the rest and digest, at GIT it causes opening of sphincters, increase gut motility and increases gut secretions

Answer 888

C) Reason Heparin: Heparin is a natural powerful anticoagulant,but its concentration in the blood is normally low, sothat only under special physiologic conditions does it have significant anticoagulant effects

Answer 889

B) Reason Vitamin C is found in fruits and vegetables. DEFICIENCY Scurvy—swollen gums, bruising, hemarthrosis, anemia, poor wound healing, perifollicular and subperiosteal hemorrhages, “corkscrew” hair. Weakened immune response.

Answer 890

B) Reason The jugular foramen lies between the petrous part ofthe temporal bone and the condylar part of the occipitalbone. It transmits the glossopharyngeal, the vagus, and theaccessory nerves

Answer 891

E) Reason The lesser omentum suspends the lesser curvature ofthe stomach to the fissure for the ligamentum venosum andthe porta hepatis and caudate lobe of the liver. The gastrosplenic omentum (ligament) connects the stomach tothe hilus of the spleen.

Answer 892

B) Reason Visual cortex is located in the occipital lobe that is located in posterior cranial fossa supplied by the posterior cerebral artery.

Answer 893

E) Reason Estimates of GFR with blood urea nitrogen (BUN) and serum [creatinine]:■ Both BUN and serum [creatinine] increase when GFR decreases.Serum Creatinine clearance is used to measure GFR in chronic renal disease.■ In prerenal azotemia (hypovolemia), BUN increases more than serum creatinine and there is an increased BUN/creatinine ratio (>20:1).■ GFR decreases with age, although serum [creatinine] remains constant because of decreased muscle mass.

Answer 894

E) Reason Levator scapulae is supplied by the spinal roots of the 3rd and 4th cervical nerves, Its function is to Raises the medial borderof the scapula.

Answer 895

A) Reason Cardiac looping Primary heart tube loops to establish left-right polarity; begins in week 4 of gestation

Answer 896

A) Reason Lesch-Nyhan syndromeDefective purine salvage due to absent HGPRT, which converts hypoxanthine to IMP and guanine to GMP. Results in excess uric acid (end product of purine metabolism)production and de novo purine synthesis. X-linked recessive

Answer 897

C) Reason Undifferentiated and very aggressive.Has keratin pearls on histology.May produce ACTH, ADH, or Antibodies against presynaptic Ca2+ channels (Lambert-Eaton myasthenic syndrome). Amplification of myconcogenes common. Inoperable; treat with chemotherap

Answer 898

E) Reason Derivatives of 2nd pharyngeal Arch: Muscles of facial expression: Stapes Plus: Styloid process Digastric (posterior belly) Lesser horn and UJ:Stylohyoid body of hyoid bone Stapedius.

Answer 899

C) Reason It supplies the lateralrectus muscle. The abducent nerve is therefore responsiblefor turning the eye laterally.

Answer 900

E) Reason A defect in the rotation and fusion of the ventral and dorsal buds results in an annular pancreas which can constrict or obstruct the duodenum and result in polyhydramnios.

Answer 901

E) Reason Barrett esophagus Glandular metaplasia—replacement of nonkeratinized (stratified) squamous epithelium with intestinal epithelium (nonciliated columnar with goblets cells) in the distal esophagus. Due to chronic acid reflux (GERD).

Answer 902

C) Reason V/Q =0 = airway obstruction (shunt). In shunt, 100% O2 does not improve Po2.V/Q =∞ = blood flow obstruction (physiologic dead space). Assuming < 100% dead space, 100% O2 improves Po2

Answer 903

B) Reason Stratified squamous epithelium is found in the oral cavity, Vulva pharynx, and esophagus (non-keratinized) and in the skin (keratinizing).

Answer 904

D) Reason Musculocutaneous Nerve: Coracobrachialis, biceps brachii, and brachialis muscles; supplies the skin along the lateral border of forearm when it becomes the lateral cutaneous nerve of the forearm

Answer 905

D) Reason Key finding: granular (“muddy brown”) casts A.3 stages:1. Inciting event2. Maintenance phase—oliguric; lasts 1–3 weeks; risk of hyperkalemia, metabolic acidosis3. Recovery phase—polyuric; BUN and serum creatinine fall; risk of hypokalemiaCan be caused by ischemic or nephrotoxic injury.

Answer 906

E) Reason Submucosa—includes Submucosal nerve plexus (Meissner)- secretionsMuscularis externa—includes Myenteric nerve plexus (Auerbach)- gut motility.

Answer 907

D) Reason Sartoriua is long and strong muscle and it takes origin from the anterior superior Iliac spine (ASIS). Its avulsion can cause fracture of ASIS.

Answer 908

B) Reason The middle meningeal artery ascends between theroots of the auriculotemporal nerve to enter the skull throughthe foramen spinosum. It runs laterally within the skull anddivides into anterior and posterior branches. The anteriorbranch is particularly important, because it lies close to themotor area of the cerebral cortex. It injury can cause loss of vision.

Answer 909

D) Reason Abduction: Middle fibers of the deltoid muscle, assistedby the supraspinatus muscle (overhead abduction).

Answer 910

D) Reason It descends in front of theopening into the lesser sac and passes behind the first partof the duodenum and then the head of the pancreas. Thebile duct ends below by piercing the medial wall of the duodenum approximately halfway down its length. Itis usually joined by the main pancreatic duct, and, together,they open into a small ampulla in the duodenal wall calledthe ampulla of Vater

Answer 911

D) Reason Clinically, theenlarged subcutaneous anastomosis between the lateral thoracic vein, a tributary of the axillary vein, andthe superficial epigastric vein, a tributary of thefemoral vein, may be seen on the thoracoabdominalwall.

Answer 912

C) Reason Choroid plexus secretes CSF into all ventricles. Arachnoid granulations (Arachnoid villi) are sites of CSF resorption

Answer 913

A) Reason MEDIAN NERVE AND RESTRICTED SPACEIn the carpal tunnel the median nerve lies in a restricted space between the flexor digitorum superficialis and the flexor carpi radialis muscles. It may become compressed at this site. Manifests as loss of sensation of thenar eminence and loss of opposition of thumb.

Answer 914

E) Reason Anterior interosseousbranch of themedian nerve supplies the flexor pollisus longus, its damage can cause addiction and lateral rotation of thumb.

Answer 915

E) Reason Nerves originating from Pons are: V. The trigeminal (mixed).VI. The abducent (motor).VII. The facial (mixed).VIII. The vestibulocochlear (sensory).

Answer 916

D) Reason CLL: Age: > 60 years. CD20+, CD5+ B-cell neoplasm. Often asymptomatic, progresses slowly; smudge cells in peripheral blood smear; autoimmune hemolytic anemia.

Answer 917

B) Reason When there is decreased Blood volume or ECF and in case of increased ECF Osmolarity, thirst center is actived in order to take ECF Osmolarity and ECF volume towards normal.

Answer 918

E) Reason The anterior cruciate ligament is attached below tothe anterior intercondylar area of the tibia, and itpasses upward, backward, and laterally to be attached to thelateral femoral condyle.

Answer 919

B) Reason Genitofemoral: Cremaster muscle in scrotum in male;nerve (L1, 2) skin over anterior surface of thigh;nervous pathway forcremasteric reflex

Answer 920

A) Reason SENSORY INNERVATION• Anterior two thirds: The lingual nerve (general sensation) and chorda tympani (taste).• Posterior third: The glossopharyngeal nerve, tractus solitarius nucleus(general sensation and taste).

Answer 921

D) Reason The submandibular ganglion is a parasympathetic ganglionthat lies deep to the submandibular salivary gland and is attached to the lingual nerve by small nerves.

Answer 922

A) Reason Most common enzymatic disorder of RBCs.X-linked recessive.Defect in G6PD: dec. glutathione inc. RBC susceptibility to oxidant stress. Hemolytic anemia following oxidant stress (classic causes: sulfa drugs, antimalarials, infections, fava beans)

Answer 923

A) Reason Ectocervix Stratified squamous epithelium, nonkeratinizedEndocervix Simple columnar epithelium-less smooth muscles.Transformation zone Squamocolumnar junction (most common area for cervical cancer)

Answer 924

D) Reason During 1st stage, cervical dilatation and effacement is important. During 2nd stage, utrine contraction is important. While during 3rd stage utrine contraction and involution is important.

Answer 925

A) Reason Third week: Gastrulation and early development of nervous and cardiovascular systems; corresponds to first missed period.

Answer 926

E) Reason Diffusion: Vgas = A/T × Dk(P1 – P2) where A = area, T = thickness, and Dk(P1 – P2) ≈difference in partial pressures: A dec. in emphysema. T inc. in pulmonary fibrosis.

Answer 927

E) Reason Theartery descends through the femoral triangle andthe adductor canal (can be damaged by compression over the canal), and it leaves the front of the thigh by passing through the opening in the adductor magnus and then entering the popliteal space as the popliteal artery.

Answer 928

E) Reason Renal clearance Cx = UxV/Px = volume of plasma from which the substance is completely cleared per unit time. = 100 x 2 / 10= 20.

Answer 929

E) Reason Rough endoplasmic reticulum:Site of synthesis of secretory (exported) proteins and of N-linked oligosaccharide addition to many proteins.

Answer 930

C) Reason Speed of conduction—Purkinje > atria > ventricles > AV node.Pacemakers—SA > AV > bundle of His/Purkinje/ventricles

Answer 931

D) Reason Fever1. Pyrogens increase the production of interleukin-1 (IL-1) in phagocytic cells. ■ IL-1 acts on the anterior hypothalamus to increase the production of prostaglandins. Prostaglandins increase the set-point temperature, setting in motion the heat-generating mechanisms that increase body temperature and produce fever.

Answer 932

B) Reason Brachioradialis is supplied by Radial nerve. It Flexes the forearm at theelbow joint, rotates theforearm to the midproneposition

Answer 933

C) Reason T4 is major thyroid product; converted to T3 in peripheral tissue by 5"-deiodinase.Free form of T3 (active form) binds receptors with greater affinity than T4.Peroxidase is enzyme responsible for oxidation and organification of iodide as well as coupling of monoiodotyrosine (MIT) and diiodotyrosine (DIT).

Answer 934

D) Reason Left anterior descending artery (LAD) Branch of LCA—supplies anterior 2/3 of interventricular septum, anterior papillarymuscle, and anterior surface of left ventricle

Answer 935

B) Reason BLOOD SUPPLY OF THE LUNGSThe bronchi, connective tissue, and visceral pleura are supplied by the bronchial arteries

Answer 936

A) Reason LTC4, D4, and E4 function in bronchoconstriction, vasoconstriction, contraction of smooth muscle, and inc. vascular permeability.PGI2 inhibits platelet aggregation and promotes vasodilation

Answer 937

E) Reason The bones are connected by the interossesous ligament . Example includes radioulnar joint and inferior tibiofibular joint.

Answer 938

E) Reason Severe combined immunodeficiency (SCID): Failure to thrive, chronic diarrhea, thrush. Recurrent viral, bacterial, fungal, and protozoal infections.Treatment: bone marrow transplant (no concern for rejection).

Answer 939

C) Reason The internal jugular vein is a large vein that drains bloodfrom the brain, face, scalp, and neck. It starts as acontinuation of the sigmoid venous sinus and leaves theskull through the jugular foramen. It then descends throughthe neck in the carotid sheath lateral to the vagus nerve andanterior to the acessary nerve and the internal and the common carotid arteries.

Answer 940

A) Reason ■ stimulates H+ secretion by activating H2 receptors on the parietal cell membrane.■ The H2 receptor is coupled to adenylyl cyclase via a Gs protein.■ The second messenger for histamine is cAMP.■ H2 receptor–blocking drugs, such as cimetidine, inhibit H+ secretion by blocking the stimulatory effect of histamine

Answer 941

A) Reason In order to ensure the best communication between the Dr. and Patients, it is necessary to explain the procedure.

Answer 942

E) Reason Glutaraldehyde, which has two reactive aldehyde groups, is 10times more effective than formaldehyde and is less toxic. In hospitals, it is used tosterilize respiratory therapy equipment, HIV and HBV used instruments, endoscopes, and hemodialysis equipment.

Answer 943

E) Reason Spinal nerves: There are mixed nerves, 31 nerves in total: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal.Nerves C1–C7 exit above the corresponding vertebra. All other nerves exit below (e.g., C3 exits above the 3rd cervical vertebra; L2 exits below the 2nd lumbar vertebra).

Answer 944

A) Reason External Carotid ArteryThe external carotid artery begins at the level of the upperborder of the thyroid cartilage as one of the terminalbranches of the common carotid artery. It ascendsto terminate in the parotid salivary gland behind the neck ofthe mandible, where it divides into the superficial temporaland the maxillary arteries.

Answer 945

C) Reason Visual field defects: 1. Ipsilatral anopia (optic nerve).2. Bitemporal hemianopia (pituitary lesion, chiasm)3. contralatral omonymous hemianopia ( optic tract lesiong

Answer 946

B) Reason The hyoid bone may be felt a few centimetres below and behind the chin, especially if the neck isextended. It may be palpated between finger and thumb and moved from side to side. The hyoid bone liesapproximately at the level of the third cervical vertebra.

Answer 947

C) Reason Type I cells 97% of alveolar surfaces. Line the alveoli. Squamous; thin for optimal gas diffusion

Answer 948

D) Reason Hemoglobin development:Fetal hemoglobin (HbF) = α2γ2.Adult hemoglobin (HbA) = α2β2.HbF has higher affinity for oxygen due to less avid binding of 2,3-BPG. This allows HbF to extract oxygen from (HbA) maternal hemoglobin across the placenta.

Answer 949

B) Reason Each gland consists of 15 to 20 lectiferous ducts that radiate outward from the nipple. There is no capsule. Each lobe is separated from its neighbor by connective tissue septa that extend from the skin to the deep fascia and that serve assuspensory ligaments. Th

Answer 950

C) Reason Associated with cystic medial degeneration due to hypertension (older patients) or Marfan syndrome (younger patients). Presents with intercostal pulsation with notching on X-ray chest. Also historically associated with 3° syphilis (obliterative endarteritis of the vasa vasorum).

Answer 951

B) Reason Compliance—change in lung volume for a given change in pressure; dec. in pulmonary fibrosis, pneumonia, and pulmonary edema; inc. in emphysema and normal aging

Answer 952

D) Reason Covering layers of the spermatic cord are from anterior abdominal wall:• External spermatic fascia derived from the externaloblique muscle and attached to the margins of the superficial inguinal ring.• Cremasteric fascia derived from the internal obliquemuscle.• Internal spermatic fascia derived from the fasciatransversalis and attached to the margins of the deep inguinal ring.

Answer 953

A) Reason Uterine artery: This artery runs medially on the floor ofthe pelvis and crosses the ureter superiorly. Itpasses above the lateral fornix of the vagina to reach theuterus, where it ascends between the layers of the broadligament along the lateral margin of the uterus.

Answer 954

B) Reason Disordered epithelial growth; begins at basal layer of squamocolumnar junction (transition zone) and extends outward. Classified as CIN 1, CIN 2, or CIN 3 (severe dysplasia or carcinoma in situ), depending on extent of dysplasia. Associated with HPV 16 and HPV 18, which produce both the E6 gene product (inhibits p53 suppressor gene) and E7 gene product (inhibits RB suppressor gene)

Answer 955

A) Reason Amphiarthroses are joints at which slight movement is possible. A pad of cartilage lies between the bone surfaces, and there are fibrous ligaments to hold the bones and cartilage in place. The cartilages of such joints also act as shock absorbers, e.g. the intervertebral discs

Answer 956

E) Reason Carrier state of S. typhi resides in gall bladder, and is asymptomatic state of the typhoid fever.

Answer 957

C) Reason C2—posterior half of a skull “cap.”C3—high turtleneck shirt.C4—low-collar shirt. C5--deltoid, C6--lateral one and half digits.

Answer 958

E) Reason Abduction: Flexor carpi radialis, extensor carpi radialislongus and brevis, abductor pollicis longus, and extensorpollicis longus and brevis muscles.• Adduction: Flexor and extensor carpi ulnaris muscles.

Answer 959

E) Reason The atheromas can develop from the fatty streak, a lesion that is characterized by focal accumulations in the intima of lipid-laden foam cells that may appear as early as the first year of life and that is present in the aorta of most older children.

Answer 960

D) Reason Adhesion (a) Vessel injury exposes subendothelial collagen, leading to platelet adhesion (adherence to the subendothelial surface) . (b) Interaction of specific platelet-surface glycoprotein receptors and subendothelial collagen is mediated by von Willebrand factor.

Answer 961

D) Reason The basilar artery ascends in a groove on theanterior surface of the pons. It gives off branches to thepons, the cerebellum, and the internal ear. It finally dividesinto the two posterior cerebral arteries.

Answer 962

C) Reason Anatomically, there are only four dorsal interossi from 1st digit to the 4th one. Hence dorsal interossous will not be affected in little finger (5th digit) injury.

Answer 963

B) Reason The costocervical trunk runs backward over the dome ofthe pleura and divides into the superior intercostalartery, which supplies the first and the second intercostalspaces, and the deep cervical artery, which supplies thedeep muscles of the neck.

Answer 964

B) Reason The atheromas can develop from the fatty streak, a lesion that is characterized by focal accumulations in the intima of lipid-laden foam cells that may appear as early as the first year of life and that is present in the aorta of most older children

Answer 965

C) Reason The vertebral artery ascends in the neck through theforamina in the transverse processes of the upper six cervical vertebrae . It supplies the occipital lobe.

Answer 966

C) Reason Iliofemoral LigamentThe iliofemoral ligament is the strongest and most importantligament of the hip joint . It is shaped like an inverted Y. Its base is attached to the anteroinferior iliac spineabove, and the two limbs of the Y are attached to the upperand the lower parts of the intertrochanteric line of the femur

Answer 967

E) Reason Rheumatic fever:A consequence of pharyngeal infection with group A β-hemolytic streptococci. Early deaths due to myocarditis. Late sequelae include rheumatic heart disease, which affects heart valves—mitral > aortic >> tricuspid (high-pressure valves affected most).

Answer 968

B) Reason Type IV: Multiple sclerosisGuillain-Barré syndromeGraft-versus-host diseasePPD (test for M. tuberculosis)Contact dermatitis (e.g., poison ivy, nickel allergy)

Answer 969

D) Reason Each ovary is attached to the back of the broad ligament bythe mesovarium . The ovarian vessels and nerves(through the broad ligament)enter the ovary at the hilum

Answer 970

E) Reason Facial nerve nucleus arises from the Pons, in lesions of the Pons the will be hemiplegia and the facial nerve palsy of the other side.

Answer 971

C) Reason In an any Inflammatory or the obstruction of the billiary tract, there is raised level of the ALP, like in choledocholithiasis, cholangitis and obstruction.

Answer 972

E) Reason Extensor pollicis longus Extends the distal phalanxof the thumbExtensor indicis Extends the metacarpophalangeal joint of theindex finger, Both are supplied by deep branch of radial nerve.

Answer 973

A) Reason The external laryngeal nerve is motor; it is located closeto the superior thyroid artery and supplies the cricothyroidmuscle. It is mostly injured in lower lobe thyroid surgery.

Answer 974

D) Reason Otic GanglionThe otic ganglion is a parasympathetic ganglion that is located medial to the mandibular nerve just below the skull,and it is inferior to the foramen ovale and adherent to the medial pterygoid muscle.

Answer 975

E) Reason Leishmania donovani: Transmitted by Sandfly, causes Visceral leishmaniasis (kala-azar): spiking fevers, lymphadenopathy,hepatosplenomegaly, pancytopenia.

Answer 976

C) Reason Mitochondria are the cellular organelle that have their own DNA as their genetic material and hence can replicate their own.

Answer 977

B) Reason Vein:The renal vein, right one is slightly higher and just anterior to aorta, drains into the inferior vena cava.

Answer 978

C) Reason Branches of Sacral plexus: The sciatic nerve (L4 and 5; S1, 2, and 3) is the largestnerve in the body and the largest branch of the sacralplexus.• The superior gluteal nerve supplies the gluteus medius,the gluteus minimus, and the tensor fasciae latae muscles.• The inferior gluteal nerve supplies the gluteus maximusmuscle.• The nerve to the quadratus femoris muscle also supplies the inferior gemellus muscle.• The nerve to the obturator internus muscle also supplies the superior gemellus muscle.• The posterior cutaneous nerve of the thigh suppliesthe skin of the buttock and the back of the thigh.

Answer 979

E) Reason COX-2 inhibitors (celecoxib)MECHANISM: Reversibly inhibit specifically the cyclooxygenase (COX) isoform 2, which is found in inflammatory cells and vascular endothelium and mediates inflammation and pain; spares COX-1, which helps maintain the gastric mucosa.

Answer 980

E) Reason MECHANISM: Sulfonamide loop diuretic. Inhibits cotransport system (Na+/K+/2 Cl-) of thick ascending limb of loop of Henle. Abolishes hypertonicity of medulla, preventing concentration of urine. Stimulates PGE release (vasodilatory effect on afferent arteriole); inhibited by NSAIDs.

Answer 981

A) Reason Proteins are nuitrional constituents that are present in different parts of the body and are the essential part of the balanced diet. Nuitrional assessment is checked by body proteins contents (kwashirkow etc)

Answer 982

D) Reason Nucleolus: The nucleolus is responsible for ribosomal RNA (rRNA) synthesis and ribosome assembly. It contains high concentration of the RNA.

Answer 983

E) Reason Autophagy of cellular components involves generation of autophagic vacuoles. These vacuoles fuse with lysosomes whose hydrolytic enzymes breakdown cellular components. It is an irreversible cell injury.

Answer 984

C) Reason REGULATION Released in pulses in response to growth hormone–releasing hormone (GHRH). Secretion inc. during exercise and sleep. Secretion inhibited by glucose and somatostatin.

Answer 985

C) Reason Blood Circulation The renal artery enters the kidney at the hilum, near the ureter. The artery branches into interlobar arteries, which travel to the medulla-cortex border remaining outside the medullary pyramids.

Answer 986

D) Reason The head is disc shaped and lies withinthe concavity of the C-shaped duodenum just posterior to the IVC.

Answer 987

D) Reason Invasive carcinoma• Cells have invaded basement membrane using collagenases and hydrolases (metalloproteinases)• Can metastasize if they reach a blood or lymphatic vessel

Answer 988

B) Reason Iliohypogastric Nerve (L1) External oblique, internal oblique,transversus abdominis musclesof anterior abdominal wall;skin over lower anteriorabdominal wall over the ileac fossa and buttock.

Answer 989

D) Reason BOUNDARIES OF THE EPIPLOIC FORAMEN• Anteriorly: Free border of the lesser omentum, the bileduct, the hepatic artery, and the portal vein.• Posteriorly: Inferior vena cava.• Superiorly: Caudate process of the caudate lobe of theliver.• Inferiorly: First part of the duodenum.

Answer 990

D) Reason Lymph DrainageFrom the fundus, the lymph vessels follow the ovarian arteryto the para-aortic nodes at the level of the first lumbar vertebra. From the body and the cervix, the lymph vessels draininto the internal and the external iliac nodes. In addition, afew lymph vessels pass through the inguinal canal to the superficial and deep (especially in late stage of malignancy) inguinal nodes.

Answer 991

C) Reason hypocalcemia--Tetany:Chvostek sign—tapping of facial nerve (tap the Cheek) inc. contraction of facial muscles.Trousseau sign—occlusion of brachial artery with BP cuff (cuff the Triceps) lead yo carpal spasm

Answer 992

D) Reason Hematocrit Mean: is the percentage of blood volume that is consisted of the blood cellular corpuscles, largely contributed by RBCs.

Answer 993

E) Reason interosseous nerve which is continuation of deep branch of radial nerve is the correct answer.

Answer 994

B) Reason Tubuloglomerular feedback, in which increased renal arterial pressure leads to increased delivery of fluid to the macula densa. The macula densa senses the increased load and causes constriction of the nearby afferent arteriole, increasing resistance to maintain constant blood flow

Answer 995

A) Reason physiologic dead space = anatomic dead space of conducting airways plus functional dead space in alveoli; apex of healthy lung is largest contributor of functional dead space. Volume of inspired air that does not take part in gas exchange.

Answer 996

A) Reason Morphologic manifestations include disorderly maturation and spatial arrangement of cells; marked variability in nuclear size and shape (pleomorphism) ; and increased, often abnormal, mitosis.

Answer 997

E) Reason Anti-aggregation factors:PGI2 and NO (released by endothelial cells) ↑ blood flow ↓ platelet aggregation

Answer 998

A) Reason Renal fascia: This is a condensation of areolar tissue outside the perirenal fat. It encloses the kidneys and thesuprarenal glands

Answer 999

D) Reason Portal hypertension is characterized by the development of venous collaterals with varices in the submucosal veins of the esophagus, the hemorrhoidal plexus, and other sites. This condition is often classified by the site of portal venous obstruction

Answer 1000

B) Reason Acute marginal artery—is on the right side and is the branch of the RCA, itsupplies right ventricleand the inferior surface of the heart.

Answer 1001

C) Reason Autosomal dominant: Often due to defects in structural genes. One of the parents is affected to transfer the trait. Many generations, both male and female, affected.

Answer 1002

D) Reason Grade: Determined by degree of cellular differentiation and mitotic activity on histology. Usually graded 1–4; 1 = low grade, well differentiated; 4 = high grade, poorly differentiated, anaplastic.

Answer 1003

A) Reason When the atmosphere temperature is greater than the body temperature, sympathetic system activation causes periphral Vasodilation and sweating to loose extra heat.

Answer 1004

E) Reason Vitamin D. As 70%Stones are calcium stones so factor that will inc calcium will be responsible for it so vit D is correct answer.

Answer 1005

E) Reason Early proximal convoluted tubule (PCT)—contains brush border. Reabsorbs all of the glucose and amino acids and most of the HCO3–, Na+, Cl–, PO43–, K+, and H2O. Isotonic absorption.

Answer 1006

E) Reason It passes forward through the cavernoussinus (mostly affected by sinus infection) with the internal carotid artery, enters the orbitthrough the superior orbital fissure, and supplies the lateralrectus muscle. The abducent nerve is therefore responsiblefor turning the eye laterally.

Answer 1007

E) Reason Type III SLEPolyarteritis nodosaPoststreptococcal glomerulonephritisSerum sicknessArthus reaction (e.g., swelling and inflammation following tetanus vaccine).

Answer 1008

B) Reason SCC: Hilar mass arising from bronchus; Cavitation; Cigarettes; hyperCalcemia (produces PTHrP).Keratin pearls and intercellular bridges

Answer 1009

E) Reason REGULATION Glucose is major regulator of insulin release. GH (causes insulin resistance inc. insulin release) and β2-agonists inc. insulin. One potent inhibitor of insulin is Somatostatin.

Answer 1010

C) Reason Layers of the Heart Wall:The heart wall is composed of 3 distinct layers: an outer epicardium, a middle myocardium and an inner endocardium. The epicardium, or visceral layer of serous pericardium, consists of a simple squamous epithelium (mesothelium) and its underlying connective tissue

Answer 1011

D) Reason In most people, the inferior cervical ganglion is fused to thefirst thoracic ganglion to form the stellate ganglion. It is located between the transverse process of the seventh cervical vertebra and the neck of the first rib.

Answer 1012

A) Reason Hippocampus (bilateral):Anterograde amnesia—inability to make new and short termmemories

Answer 1013

C) Reason p53 and hypophosphorylated Rb normally inhibit G1-to-S progression; mutations in these genes result in unrestrained cell division (e.g., Li-Fraumeni syndrome). p53 also prevents the overcrowding if the cells.

Answer 1014

C) Reason Myelodysplastic syndromesStem cell disorders involving ineffective hematopoiesis defects in cell maturation of all non-lymphoid lineages. Caused by de novo mutations or environmental exposure (e.g., radiation, benzene, chemotherapy). Risk of transformation to AML.

Answer 1015

D) Reason CBD has four parts

Answer 1016

E) Reason The face develops from 5 primordia of mesoderm (neural crest) of the first pharyngeal arch: a single frontonasal prominence, the pair of maxillary prominences, and the pair of mandibular prominences.

Answer 1017

B) Reason Fixed splitting: Seen in ASD. ASD leads toleft-to-right shunt inc. RA and RV volumes inc. flow through pulmonic valve such that, regardless of breath, pulmonic closure is greatly delayed.

Answer 1018

A) Reason Musculocutaneous Nerve Supplies: Coracobrachialis, biceps brachii, and brachialis muscles; supplies the skin along the lateral border of forearm when it becomes the lateral cutaneous nerve of the forearm.

Answer 1019

E) Reason baroreceptors respond to the decrease in arterial pressure by decreasing the firing rate of the carotid sinus nerves. A coordinated response from the vasomotor center then increases sympathetic outflow to the heart and blood vessels and decreases parasympathetic outflow to the heart. As a result, heart rate, contractility, decreased venous complience, TPR, and venous return increase, and blood pressure increases toward normal.

Answer 1020

D) Reason Inversion (movement of the foot so that the sole facesmedially): Tibialis anterior, extensor hallucis longus, medial tendons of extensor digitorum longus, and tibialis posterior muscles.

Answer 1021

B) Reason PT—tests function of common and extrinsic pathway (factors I, II, V, VII, and X). Defect increases PT. PTT—tests function of common and intrinsic pathway (all factors except VII and XIII). Defect increases PTT.

Answer 1022

E) Reason Pterygomandibular Ligament: Connects the hamularprocess of the medial pterygoid plate to the posterior end ofthe mylohyoid line of the mandible. It also gives attachmentto the superior constrictor and the buccinator muscles.

Answer 1023

A) Reason Eversion (opposite movement of the foot so that the solefaces laterally): Peroneus longus, peroneus brevis, peroneus tertius, and lateral tendons of extensor digitorumlongus muscles.

Answer 1024

A) Reason ARTERIESLateral thoracic and thoracoacromial arteries, branches ofthe axillary artery, and perforating branches of the internalthoracic and intercostal arteries supply the breast.

Answer 1025

C) Reason Chromaffin cells are neural crest cells, which migrate into the adrenal medulla to form postganglionic sympathetic neurons. That reaches the gland through renal plexus.

Answer 1026

C) Reason Sympathetic system is characterized by fight and flight, here the student"s sympathetic system was activated due to stress laeding to sec. TPR and cuase hypotension and syncope.

Answer 1027

B) Reason V/Q is 0 = airway obstruction (shunt). In shunt, 100% O2 does not improve Po2.V/Q is ∞ = blood flow obstruction (physiologic dead space). Assuming < 100% dead space, 100% O2 improves Po2.

Answer 1028

E) Reason The foramen ovale lies posterolateral to the foramen rotundum. It perforates the greater wing of the sphenoid, and it transmits the acessary meningeal artery, the sensory and the motor roots of themandibular division of the trigeminal nerve. It also transmitsthe lesser petrosal nerve (p. 232).

Answer 1029

E) Reason Primary cartilaginous joints (synchondrosis, or hyaline cartilage joints): The bones are united by a plate of hyaline cartilage so that the joint is immovable and strong.

Answer 1030

C) Reason Muscular dystrophy (most commonly Duchenne): X-linked recessive deletion of dystrophin gene.

Answer 1031

A) Reason FRACTURES OF THE FACIAL BONESNasal fractures, because of the prominence of thenose are the most common facial fractures. Fracturesof the maxilla are common and usually result from adirect anteroposterior blow to the face

Answer 1032

A) Reason FUNCTION Catabolic effects of glucagon:Glycogenolysis, gluconeogenesisLipolysis and ketone production

Answer 1033

D) Reason CK-MB is predominantly found in myocardium but can also be released from skeletal muscle. Useful in diagnosing reinfarction following acute MI because levels return to normal after 48 hours.

Answer 1034

E) Reason Sympathetic system is characterized by fight and flight, It causes puplillary dilatation while parasympathetic stimulation causes pupillary construction.

Answer 1035

D) Reason Stimuli for secretion of gastrin■ Gastrin is secreted from the G cells of the gastric antrum in response to a meal.■ Gastrin is secreted in response to the following:(1) Small peptides and amino acids in the lumen of the stomach ■ The most potent stimuli for gastrin secretion are phenylalanine and tryptophan.

Answer 1036

E) Reason The anterior and posterior longitudinal ligaments runas continuous bands down the anterior and the posteriorsurfaces of the vertebral column from the skull to thesacrum and provide stability to vertebral bodies.

Answer 1037

B) Reason Optic tract lesion causes contralatral Homonemous hemianopia, hence in rigjt optic tract lesion, left homonymous hemianopia will be the manifestation.

Answer 1038

A) Reason Broca: Nonfluent motor aphasia with intact comprehension.Broca area—inferior frontal gyrus of frontal lobe

Answer 1039

E) Reason The functionalis is the part that is sloughed off at menstruation and parturation then replaced during each menstrual cycle, and the basalis is the portion retained after menstruation that subsequently proliferates and provides a new epithelium and lamina propria.

Answer 1040

E) Reason Parietal PleuraThe parietal pleura is sensitive to pain, temperature, touch,and pressure. The costal pleura is supplied by the intercostal nerves, the mediastinal pleura by the phrenic nerve,and the diaphragmatic pleura over the domes by thephrenic nerve and around the periphery by the lower intercostal nerves.Visceral PleuraThe visceral pleura receives an autonomic nerve (sympathetic ) supplyfrom the pulmonary plexus. It is sensitive only to stretching.

Answer 1041

E) Reason V4 is one of the anteriorolateral chest lead, Left anterior descending artery (LAD)—supplies anterior 2/3 of interventricular septum, anterior papillarymuscle, and anterior surface of left ventricle.

Answer 1042

D) Reason pain in myocarditis is not affected by respiration.

Answer 1043

B) Reason SENSORY INNERVATION• Anterior two thirds: The lingual nerve (general sensation) and chorda tympani (taste).• Posterior third: The glossopharyngeal nerve (nucleus of tractus solitarius, general sensation and taste).

Answer 1044

A) Reason IgE: Binds mast cells and basophils; cross-links when exposed to allergen, mediating immediate (type I) hypersensitivity through release of inflammatory mediators such as histamine. Mediates immunity to worms by activating eosinophils. Lowest concentration in serum

Answer 1045

E) Reason In severe form of the Rh incompatiblility as in subsequent pregnancies, the excessive level of bilurubin also deposits in brain (basal ganglia) causing CNS symptoms known as Kernecterus.

Answer 1046

D) Reason Relaxation occurs when Ca2+ is reaccumulated by the SR Ca2+-ATPase (SERCA). Intracellular Ca2+ concentration decreases, Ca2+ is released from troponin C, and tropomyosin again blocks the myosin-binding site on actin. As long as intracellular Ca2+ concentration is low, cross-bridge cycling cannot occur

Answer 1047

D) Reason Brachioradialis is Supplied by Radial nerve, it Flexes the forearm at theelbow joint, rotates theforearm to the midproneposition

Answer 1048

C) Reason Creatinine is raised in patients with chronic renal failure, its level in serum indicate the effectiveness of the therapy. So less effective control indicate the renal transplantation option.

Answer 1049

C) Reason Parasympathetic system is the CranioSacral outflow while Sympathetic System is the ThoracoLumber outflow.

Answer 1050

B) Reason ■ During exercise, when demand is high, these local metabolic mechanisms are dominant.■ The local vasodilator substances are lactate, adenosine, and K+ that dec. TPR and increase blood flow.

Answer 1051

D) Reason Branches of the Median Nerve in the Forearm• Muscular branches: Pronator teres, flexor carpi radialis,palmaris longus, and flexor digitorum superficialis muscles.• Articular branches: Elbow joint

Answer 1052

D) Reason Posterior division of Sacral plexus: The nerve to the quadratus femoris muscle also supplies the inferior gemellus muscle.• The nerve to the obturator internus muscle also supplies the superior gemellus muscle.

Answer 1053

B) Reason FurosemideMECHANISM Sulfonamide loop diuretic. Inhibits cotransport system (Na+/K+/2 Cl-) of thick ascending limb of loop of Henle. Abolishes hypertonicity of medulla, preventing concentration of urine. Stimulates PGE release (vasodilatory effect on smooth muscles on afferent arteriole); inhibited by NSAIDs.

Answer 1054

C) Reason External Carotid ArteryThe external carotid artery begins at the level of the upperborder of the thyroid cartilage as one of the terminalbranches of the common carotid artery.

Answer 1055

D) Reason Most important step in coagulation pathway is the formation of the fibrin from Fibrinogen. then Fibrin mesh acts tostabilize platelet plug

Answer 1056

C) Reason ■ is the difference between the systolic and diastolic pressures.■ The most important determinant of pulse pressure is stroke volume. As blood is ejected from the left ventricle into the arterial system, arterial pressure increases because of the relatively low capacitance of the arteries. Because diastolic pressure remains unchanged during ventricular systole, the pulse pressure increases to the same extent as the systolic pressure

Answer 1057

A) Reason Gap junctions■ are present at the intercalated disks.■ are low-resistance paths between cells that allow for rapid electrical spread of action potentials.■ account for the observation that the heart behaves as an electrical syncytium.

Answer 1058

A) Reason ■ Fast pain is carried by group III fibers. It has a rapid onset and offset, and is localized.■ Slow pain is carried by C fibers. It is characterized as aching, burning, or throbbing that is poorly localized

Answer 1059

C) Reason ■ Total body water (TBW) is approximately 60% of body weight.■ The percentage of TBW is highest in newborns and adult males and lowest in adult femalesand in adults with a large amount of adipose tissue.

Answer 1060

C) Reason Condylomata acuminata: Caused by HPV 6 and 11.Genital warts, koilocytes.

Answer 1061

B) Reason Constriction of arterioles causes intense peripheral vasoconstriction and increased TPR. Blood flow to other organs (e.g., kidneys) is significantly reduced in an attempt to preserve blood flow to the brain.

Answer 1062

E) Reason Osmotic damage (sorbitol accumulation in organs with aldose reductase and decrease or absent sorbitol dehydrogenase):Neuropathy (motor, sensory, and autonomic degeneration)Cataracts by accumulation of sorbitol.

Answer 1063

B) Reason ALP is raised in any obstructive cases of the billiary tract, moreover the direct bilurubin raised indicate the extra hepatic stasis of the billiary tract.

Answer 1064

C) Reason Osteogenesis imperfecta:Genetic bone disorder (brittle bone disease ) caused by a variety of gene defects.Most common form is autosomal dominant with dec. production of otherwise normal type I collagen. OI manifestations can include:Multiple fractures with minimal trauma; may occur during the birth processBlue sclerae due to the translucency of the connective tissue over the choroidal veins.

Answer 1065

E) Reason Intra-articular fibrocartilages, articular discs or menisci, complete or incomplete, help in spreading the synovial fluid throughout the joint cavity, but particularly between the articular surfaces, e.g. temporomandibular joint.

Answer 1066

D) Reason Nystagmus, diplopia, ataxia, sedation, gingival hyperplasia, hirsutism, peripheral neuropathy, megaloblastic anemia, teratogenesis (fetal hydantoin syndrome) SLE-like syndrome, induction of cytochrome P-450, lymphadenopathy, Stevens Johnson syndrome, osteopenia.

Answer 1067

B) Reason Polycythemia often presents as intense itching after hot shower. Rare but classic symptom is erythromelalgia (severe, burning pain and reddish or bluish coloration) due to episodic blood clots due to hyperviscosity in vessels of the extremities. Hyperviscosity and clots in vessels is the cause of stagnant Hypoxia.

Answer 1068

C) Reason Medial (Deltoid) LigamentThe medial ligament is very strong and is attached by itsapex to the tip of the medial malleolus. Its injury results in loss of eversion.

Answer 1069

C) Reason Primary billiary cirrhosis, PRESENTATION: Pruritus, jaundice, dark urine, light stools, hepatosplenomegaly. Confirmed by CT and MRCP.

Answer 1070

D) Reason The isthmuscrosses the midline in front of the second, the third, andthe fourth rings of the trachea. Tracheostomy is done at C2-3 and save the isthmus injury.

Answer 1071

A) Reason In the young, the epiphysis of the head is supplied bya small branch of the obturator artery, which passes tothe head along the ligament to the femoral head

Answer 1072

A) Reason In the young, the epiphysis of the head is supplied bya small branch of the obturator artery, which passes tothe head along the ligament to the femoral head

Answer 1073

C) Reason The pylorus lies on the transpyloric plane at thelevel of the first lumbar vertebra

Answer 1074

A) Reason Protamine can lessen the risk of serious bleeding that canresult from excessive unfractionated heparin by occupying its receptor site. Protamine only partially reverses the effects of LMWheparins

Answer 1075

B) Reason Natural killer cells Use perforin and granzymes to induce apoptosis of virally infected cells and tumor cells.Only lymphocyte member of innate immune system

Answer 1076

D) Reason MOVEMENTSRotation of the atlas with the head on the axis is possible.

Answer 1077

A) Reason LOWER TRUNK LESIONS OF THE BRACHIALPLEXUS (KLUMPKE PALSY)Lower trunk lesions of the brachial plexus result fromtraction injury, as in excessive abduction of the arm.The first thoracic nerve is usually torn, all the smallmuscles of the hand are paralyzed, and the patient develops a claw hand

Answer 1078

D) Reason Autonomic center of Hypothalamus■ Temperature regulation centerthrough central and periphral mechanisms.■ Thirst and food intake regulatory centers as gut distention is associated with increased serum Osmolarity and causes thirst stimulation.

Answer 1079

A) Reason SA and AV nodes are usually supplied by RCA before the origin of the marginal branch. Infarct may cause nodal dysfunction (bradycardia or heart block).

Answer 1080

E) Reason aldosterone-secreting adrenal adenoma (Conn syndrome), resulting in hypertension, hypokalemia, metabolic alkalosis, and lowplasma renin. Normal Na+ due to aldosterone escape = no edema due to aldosterone escape mechanism. May be bilateral or unilateral.

Answer 1081

E) Reason External oblique Originate from Lower right ribs where it interdigitate with serratus anterior. It is inserted into the Xiphoid process, linea alba, pubic crest, pubic tubercle, iliac crest.

Answer 1082

D) Reason Pathedine is a synthetic analgesic with anti-spamodic action as well. That is the reason, it can be used in severe pain of the pancreatitis.

Answer 1083

C) Reason QRS complex—ventricular depolarization (normally < 120 msec). It the time taken by conductive system to conduct electric potential from sub-endocardium (the conductive system) to the ventricle (including its pericardium).

Answer 1084

C) Reason Bulb of the vagina is attached to the undersurface of the urogenital diaphragm and is covered by thebulbospongiosus muscles. It is the most commonly damaged muscle during mediolateral episiotomy.

Answer 1085

D) Reason Receptors are the specific type of molecules usually proteins that are present at cell surface (usually) inside cell. Receptors mediate the function of a ligand molecule or stimulus.

Answer 1086

C) Reason Mature long bones are covered on all surfaces by dense cortical bone with an outer periosteum, with the exception of articular surfaces, which are covered by hyaline articular cartilage. Transplanted bones are replaced by this periostium.

Answer 1087

B) Reason Chemotactic products released in response to bacteria: C5a, IL-8, LTB4, kallikrein, platelet-activating factor

Answer 1088

E) Reason Measurement of renal plasma flow (RPF)—clearance of para-aminohippuric acid (PAH)■ PAH is filtered and secreted by the renal tubules.■ Clearance of PAH is used to measure RPF.

Answer 1089

B) Reason Hypersegmented neutrophils, pancytopenia, glossitis, dec. B12, inc. homocysteine, inc. methylmalonic acid.Neurologic symptoms: subacute combined degeneration (due to involvement of B12 in fatty acid pathways and myelin synthesis):

Answer 1090

A) Reason Normal saline is with NaCl concentration of 0.9 percent, That means 0.9g in 100ml and 9g in 1000ml.

Answer 1091

D) Reason Positive skew Typically, mean > median > mode. Asymmetry with longer tail on right. Negative skew: Typically, mean < median < mode.

Answer 1092

D) Reason Cross-sectional study:Collects data from a group of people to assess frequency of disease (and related risk factors) at a particular point in time.Asks, “What is happening?”

Answer 1093

E) Reason superficial plexus lies beneath the visceral pleura anddrains over the surface of the lung toward the hilum, wherethe lymph vessels enter the bronchopulmonary nodes.

Answer 1094

C) Reason P. malarie is a specie of the Plasmodium that is known as quatran malaria (fever spikes on fourth day) due to its long duration of about 48-72 hours of erythrocytic shizgony phase. While other species cuase tertiary malaria (fever spikes on 3rd day) due to relatively short erythrocytic shizgony phase.

Answer 1095

E) Reason In the lung, metastases (usually multiple lesions) are more common than 1° neoplasms. Most often from breast, colon, prostate, and bladder cancer. Lung cancer metastases through lymphatics to—adrenals, brain, bone (pathologic fracture), liver (jaundice, hepatomegaly).

Answer 1096

E) Reason Erythrocytes: Carries O2 to tissues and CO2 to lungs. Anucleate and biconcave, with large surface area-to-volume ratio for rapid gas exchange. Life span of 120 days.

Answer 1097

E) Reason Lymph DrainageThe lymph drains into the internal iliac nodes.Nerve SupplyInferior hypogastric plexuses supply the prostate.

Answer 1098

A) Reason NERVE SUPPLYSensory Nerves• Above the vocal folds: The internal laryngeal nerve.• Below the vocal folds: The recurrent laryngeal nerve.

Answer 1099

B) Reason Truncal vagotomy also causes disturbed motility of the antrum and pylorus of stomach besides the sec. acid secretion. That is why, truncal vagotomy causes delayed gastric emptying, and now selective vagotomy is in practice to avoid this side effect.

Answer 1100

D) Reason Macrophage rank binds to osteoblast RAN KL and macrophage becomes an osteoclast. While osteoblasts and osteocytes are the bone forming cells.

Answer 1101

B) Reason DM is a multifactorial trait that presents with Polydipsia, polyuria, polyphagia, weight loss, DKA (type 1), hyperosmolar coma (type 2).Rarely, can be caused by unopposed secretion of GH and epinephrine.

Answer 1102

A) Reason Esophageal varices Painless bleeding of dilated submucosal veins in lower 1 ⁄3 of esophagus 2° to portal hypertension

Answer 1103

C) Reason Platysma Muscle is supplied by the spinal part of the facial nerve, It Depresses themandible and angleof the mouth

Answer 1104

E) Reason Blood reaction that doesn"t involve the severe manifestations of the anaphylactic shock, is a simple febrile reaction and is easily managed by antioyretics and close monitoring.

Answer 1105

A) Reason benzathine penicillin once each month for several years) in persons who have hadrheumatic fever is important to prevent recurrence of the disease. There is noevidence that patients who have had AGN require similar penicillin prophylaxis

Answer 1106

A) Reason Zona glomerulosa is the part of the adrenal cortex that secrets Aldosterone in an influence of renin-Angiotensin-aldosterone system of blood pressure control.

Answer 1107

E) Reason Type IV Delayed (T-cell-mediated) type—sensitized T lymphocytes encounter antigen and then release lymphokines (leads to macrophage activation; no antibody involved).

Answer 1108

C) Reason Preganglionic neurons of the sympathetic nervous system originate in spinal cord from lateral horns of the segments T1–L3 or the thoracolumbar region. So, there is no lateral horn bellow L3.

Answer 1109

A) Reason Hypertonic solution causes the shrinkage of the cells and outflow of fluids outside the cell leading to increased ECF volume.

Answer 1110

B) Reason TOXICITY: Hyperchloremic metabolic acidosis, paresthesias, NH3 toxicity, sulfa allergy

Answer 1111

E) Reason Internal iliac artery is damaged.

Answer 1112

B) Reason Pretracheal LayerThe pretracheal layer is a thin layer that is attached above tothe laryngeal cartilages. It surrounds the thyroid gland.

Answer 1113

E) Reason The inferior thyroid artery ascends to reach the posterior surface of the thyroid gland, where it is closely relatedto the recurrent laryngeal nerve. The inferior thyroidartery supplies the thyroid, thymus and the inferior parathyroidglands.

Answer 1114

D) Reason Toxoplasma gondii, a protozoa:Brain abscess in HIV (seen as ring-enhancing brain lesions on CT/MRI); congenital toxoplasmosis = “classic triad” of chorioretinitis, hydrocephalus, and intracranial calcifications

Answer 1115

E) Reason In myelinated neurons, the area in between the myelinated parts is called the node of ranvier where there is no myelin. It is responsible for rapid conduction, the saltatory conduction.

Answer 1116

D) Reason Insulin-dependent glucose transporters:GLUT-4: adipose tissue, skeletal muscleInsulin-independent transporters:GLUT-1: RBCs, brain, corneaGLUT-5 (fructose): spermatocytes, GI tractGLUT-2 (bidirectional): β islet cells, liver, kidney, small intestine

Answer 1117

D) Reason Aspirin is commonly used drug for pain killers and other purposes. TOXICITY of Aspirin: Gastric ulceration, tinnitus (CN VIII). Chronic use can lead to acute renal failure, interstitial nephritis, increased bleeding time, and upper GI bleeding.

Answer 1118

E) Reason Lymphatic DrainageThe lateral quadrants of the breast drain into the anterior axillary or the pectoral nodes. The medial quadrantsdrain into the internal thoracic nodes. A few lymph vesselsalso drain posteriorly into the posterior intercostal nodes,and some communicate with the lymphatic vessels of theopposite breast and with those of the anterior abdominalwall.

Answer 1119

D) Reason NERVE SUPPLYAnterior interosseous nerve (flexor and adductor of wrist) from the median and the deepbranches of the radial (extensor of wrist) and the ulnar nerves supply the wristjoint

Answer 1120

A) Reason The postganglionic secretomotorfibers reach the parotid salivary gland via the auriculotemporal nerve. Its compression is the main cause of parotid gland pain.

Answer 1121

D) Reason Staining for different tissue tumors, Vimentin: Connective tissueDesMin: MuscleCytokeratin: Epithelial cellsGFAP: NeuroGliaNeurofilaments: Neurons

Answer 1122

E) Reason 4th cranial nerve supplies the superior oblique muscle which is involved in looking downwards and medially.

Answer 1123

A) Reason The neck of the femoral hernial sac lies at the femoral ringand is related anteriorly to the inguinal ligament,posteriorly to the pectineal ligament, laterally to thefemoral vein, and medially to the sharp, free edge ofthe lacunar ligamen

Answer 1124

C) Reason Obstructive lung diseases:Obstruction of air flow resulting in air trapping in the lungs. Airways close prematurely at high lung volumes inc. RV and dec. FVC. PFTs: decreased FEV1/FVC ratio (hallmark),

Answer 1125

E) Reason Pulmonary emboli:V/Q mismatch leads to hypoxemia and respiratory alkalosis. Sudden-onset dyspnea, chest pain, tachypnea. May present as sudden death.Types: Fat, Air, Thrombus, Bacteria, Amniotic.

Answer 1126

C) Reason Collateral circulation around the shoulder joint wouldinvolve the following:A. The subscapular arteryB. The superficial cervical arteryC. The suprascapular arteryD. The anterior circumflex humeral artery, most commonly injured in anterior dislocation.

Answer 1127

E) Reason Strawberry hemangioma:Benign capillary hemangioma of infancy. Appears in first few weeks of life (1/200 births); grows rapidly and regresses spontaneously at 5–8 years old.Cherry hemangioma: Benign capillary hemangioma of the elderly. Does not regress. Frequency inc. with age.

Answer 1128

A) Reason Veins:The veins drain into the portal circulation. The right and leftgastric veins drain into the portal vein. Left gastric vein drain directly into the portal vein. The short gastric and the left gastroepiploic veins drain into the splenic vein,and the right gastroepiploic vein drains into the superiormesenteric vein.

Answer 1129

A) Reason The Cushing reaction is an example of the response to cerebral ischemia. Increases in intracranial pressure cause compression of the cerebral blood vessels, leading to cerebral ischemia and increased cerebral Pco2. The vasomotor center directs an increase in sympathetic outflow to the heart and blood vessels, which causes a profound increase in arterial pressure.

Answer 1130

D) Reason Characteristic perivascular rosettes seen in Ependymoma. Rodshaped blepharoplasts (basal ciliary bodies) found near nucleus.

Answer 1131

A) Reason False ribs: The eighth, ninth, and tenth pairs are attachedanteriorly to each other and to the seventh rib by theircostal cartilages and small synovial joints.

Answer 1132

D) Reason The saphenous opening is a gap in the deep fascia in thefront of the thigh and just below the inguinal ligament. It allows passage of the great saphenous vein, some smallbranches of the femoral artery, and lymph vessels.

Answer 1133

A) Reason The saphenous opening is a gap in the deep fascia in thefront of the thigh and just below the inguinal ligament. It allows passage of the great saphenous vein, some smallbranches of the femoral artery, and lymph vessels.

Answer 1134

C) Reason Adrenergic stimulation of α1: Hypotension (vasoconstrictor), ocular procedures (mydriatic), rhinitis (decongestant)

Answer 1135

E) Reason Cutaneous anthrax: most common presentation, Boil-like lesion and ulcer with black eschar (painless, necrotic) causes uncommonly progresses to bacteremia and death.Pulmonary anthrax: Inhalation of spores causes flu-like symptoms that rapidly progress to fever, pulmonary hemorrhage, mediastinitis, and shock.

Answer 1136

E) Reason DEFICIENCY Night blindness (nyctalopia); dry, scaly skin (xerosis cutis); alopecia; corneal degeneration (keratomalacia); immune suppression.

Answer 1137

D) Reason Granulosa cell tumor Most common sex cord stromal tumor. Predominantly women in their 50s. These are the inhibin positive tumors. Often produce estrogen and/or progesterone and present with abnormal uterine bleeding, sexual precocity (in preadolescents), breast tenderness

Answer 1138

E) Reason Hemophilia A: deficiency of factor VIII.Hemophilia B: deficiency of factor IX. These are the factors of intrinsic pathway and can be assessed by PTT.

Answer 1139

D) Reason Vitamins are abundant in vegetables and fruits. Moreover it ia an easy and cheap source of vitamins.

Answer 1140

E) Reason Carbohydrates are the main sources of energyin the body. Brain cells and RBCs are almostwholly dependent on carbohydrates as theenergy source.

Answer 1141

D) Reason A lumbar puncture is used to inject anesthetic material in the epidural space or to withdraw CSF from the subarachnoid space. • A spinal tap is typically performed at the L4 and L5 interspace.

Answer 1142

A) Reason Myosin has 3 different biological activities:a. Myosin molecules assemble into filaments.b. Myosin acts as the enzyme ATPase.c. Myosin binds to actin polymer which is the majorcomponent of the thin filaments

Answer 1143

C) Reason Increases pancreatic secretionIncreases gallbladder contractionDecreases gastric emptyingIncreases phincter of Oddi relaxation

Answer 1144

E) Reason Due to excessive and inappropriate exposure to androgenic steroids during early gestation (e.g., congenital adrenal hyperplasia or exogenous administration of androgens during pregnancy.

Answer 1145

C) Reason Forced expiration is an active process accomplished bycontraction of the muscles of the anterior abdominal wall, rectus abdominus(forcing the relaxed diaphragm upward by raising intraabdominal pressure)

Answer 1146

E) Reason Flexion: Biceps femoris, semitendinosus, and semimembranosus muscles. Bicep femoris is supplied by sciatic nerve that is why in tibial nerve lesion, bicep femoris cause some Flexion of knee.

Answer 1147

E) Reason 12- 24 hr:Occluded artery InfarctDark mottling; pale with tetrazolium stainEarly coagulative necrosis, neutrophils and release of necrotic cell contents into blood; edema, hemorrhage, wavy fibers.

Answer 1148

A) Reason FUNCTION Stimulates milk production in breast; inhibits ovulation in females and spermatogenesis in males by inhibiting GnRH synthesis and release.

Answer 1149

B) Reason Metabolic acidosis with Normal anion gap (8−12 mEq/L):HyperalimentationAddison diseaseRenal tubular acidosisDiarrheaAcetazolamideSpironolactoneSaline infusion

Answer 1150

E) Reason Folate deficiency Causes: malnutrition (e.g., alcoholics), malabsorption, antifolates (e.g., methotrexate, trimethoprim, phenytoin), increased requirement (e.g., hemolytic anemia, only iron intake, pregnancy).

Answer 1151

B) Reason Tracheostomy is an artificial mean of opening the airway through the trachea. As it is an artificial opening and it is always open, and causes heat and vapors loss continually.

Answer 1152

C) Reason Membrano-cartilaginous bones ossify partly in membrane and partly in cartilage. Examples: clavicle, mandible, occipital, temporal, sphenoid.

Answer 1153

C) Reason HLA (Human Leukocytic Antigen) are the specific type of antigens present on Leukocytes that have specific antigenicity and that is why used for tissue matching.

Answer 1154

D) Reason ■ Osmosis is the flow of water across a semipermeable membrane from a solution with low solute concentration to a solution with high solute concentration.

Answer 1155

A) Reason Midbrain—nuclei of CN III, IVPons—nuclei of CN V, VI, VII, VIIIMedulla—nuclei of CN IX, X, XIISpinal cord—nucleus of CN XI

Answer 1156

B) Reason In plasma, protein bound drugs are inactive form of the drugs while free form of the drugs that are not bound to plasma proteins are the active form of the drugs.

Answer 1157

D) Reason Lateral corticospinal tract(voluntary motor). Rubrospinal tract■ originates in the red nucleus and projects to interneurons in the lateral spinal cord.■ Stimulation of the red nucleus produces stimulation of flexors and inhibition of extensors

Answer 1158

E) Reason If a person is breathing in a paper bag, there will be increased level of CO2 accumulation that will be washed out by hyperventilation.

Answer 1159

C) Reason Type I Collagen: Most common (90%)—Bone (made by osteoblasts), Skin, Tendon, dentin, fascia, cornea, late wound repair (deficiency causes delayed and less strong wound healing).

Answer 1160

A) Reason Parkinson disease Degenerative disorder of CNS associated with Lewy bodies (composed of α-synuclein—intracellular eosinophilic inclusion) and loss of dopaminergic neurons (i.e., depigmentation) of the substantia nigra pars compacta. While GABA related CNS disorder is the Huntington disease.

Answer 1161

B) Reason DEFICIENCY Cheilosis (inflammation of lips, scaling and fissures at the corners of the mouth), Corneal vascularization.

Answer 1162

A) Reason All major organ systems begin to develop during the embryonic period (weeks 3-8). By the end of this period, the embryo begins to look human.

Answer 1163

B) Reason In the process of erythropoisis, red blood cells have their nuclei but as they mature their nuclei disappear in late stages of development and ultimately mature rbcs have no nuclei.

Answer 1164

C) Reason All the organs except descecding colon given in scenario"s option are derivatives of foregut supplied by Superior mesenteric artery, and descending colon is supplied by inferior mesenteric artery.

Answer 1165

A) Reason Damage supporting structures during childbirthor chronic Metaplasiaor as a result of general poor body muscular tone mayresult in downward displacement of the uterus, calleduterine prolapse

Answer 1166

A) Reason HaptoglobinIt is synthesized in the liver. It transports free hemoglobin inthe plasma to reticulo endothelial system.

Answer 1167

B) Reason The superior thyroid artery curves downward to the upperpole of the thyroid gland. It is accompanied by the external laryngeal nerve, which supplies thecricothyroid muscle.

Answer 1168

B) Reason Bilateral damage of the vagus nerve will lead to totally lost inervation of the heart leading to cardiac arrest and death.

Answer 1169

C) Reason TSH increases both the synthesis and the secretion of thyroid hormones by the follicular cells via an adenylate cyclase–cAMP mechanism.■ Chronic elevation of TSH causes hypertrophy of the thyroid gland

Answer 1170

B) Reason Leprosy (Hansen disease):Caused by Mycobacterium leprae, an acid-fast bacillus that likes cool temperatures (infects skin and superficial nerves—“glove and stocking” loss of sensation) and cannot be grown in vitro. Causes lymphadenopathy and typical lepromatous nose lesion.

Answer 1171

C) Reason Early proximal convoluted tubule (PCT)—contains brush border. Reabsorbs all of the glucose and amino acids and most of the HCO3–, Na+, Cl–, PO43–, K+, and H2O. About 65-80 percent of these substances are reabsorbed from PCT.