Quiz Flashcards
The distal bony attachment (insertion) of the flexor carpi ulnaris tendon includes the
A.base of the index (2nd) metacarpal. B.base of the thumb (1st) metacarpal. C.capitate. D.radius. E.pisiform.
E
Musculoskeletal ultrasound is useful for which of the following applications? (check all that apply)
A. differentiation of abscess versus cellulitis
B. identification of long-bone fractures
C. identification of (and guidance for removal of) soft tissue foreign bodies
D. identification of tendon injury
E. procedural guidance for nerve blocks
All of the above
In which of the following study types does the investigator assign the exposure or treatment? A.Ecologic study B.Randomized clinical trial C.Case report study D.Cohort study E.Case-control study F.Cross sectional study
Answer Key: B
Feedback: In clinical studies, both random and non-random, the investigators determine who gets the exposure or treatment.
The spiral groove of the humerus is a landmark to both surgeons and radiologists. The artery that accompanies the radial nerve in this groove is the
A.posterior humeral circumflex. B.radial. C.middle collateral. D.profunda brachii. E.superior ulnar collateral.
Answer Key: D
The muscle that is the prime flexor of the proximal inter-phalangeal (PIPJ) joint of the middle finger is the
A.interosseus. B.lumbrical. C.flexor digitorum superficialis. D.flexor digitorum profundus. E.flexor carpi ulnaris.
Answer Key: C
As you sit at your desk, your hand and forearm lie flat on the desk, palm up. You move so that your thumb points perpendicular to the plane of the palm. The movement that occurred is called A.flexion. B.adduction. C.pronation. D.supination E.abduction.
Answer Key: E
Entry of acetyl-CoA into the citric acid cycle decreases as
A.the ratio of [ATP]/[ADP] increases.
B.[AMP] increases.
C.the ratio of [NAD+]/[NADH] increases.
D.the rate of electron transport increases.
A
The axillary nerve, which can be visualized on an MRI scan,
A.passes through the triangular space.
B.innervates the teres major muscle.
C.has a cutaneous branch, the superior (upper) lateral brachial cutaneous nerve.
D.passes through the foramen formed by the superior transverse scapular ligament and the suprascapular notch.
E.is derived from the lateral cord of the brachial plexus.
Answer Key: C
What is the advantage of having glucose-6-phosphatase present in the hepatocyte?
A.It produces glucose from glucose-6-P which permits it to be exported for the cell.
B.It exchanges the phosphate from the 6 to the 1 position on glucose and allows it to enter the glycogen synthetic pathway
C.It exchanges the phosphate from the 1 to the 6 position on glucose and allows it to enter the glycogen synthetic pathway
D.it adds the glucose-6-P to the terminus of the growing glycogen polymer.
Answer Key: A
Feedback: Glucose - 6 -P cannot be transport out of the hepatocyte and must be phosphorylated first.
The annular ligament stabilizes the A.ulnar styloid process. B.neck of the radius. C.humerus. D.hook of the hamate to the pisiform. E.dorsal tubercle (Lister’s) of the radius.
B
Researchers conducting an investigation ito the efficacy of an anti-osteoporosis drug decided to limit participants to women over the age of 65. this is an example of reducing confounding factors by A.matching. B.stratification. C.adjustment D.inappropriate investigation bias
B
Malonyl-CoA inhibits ß-oxidation at which step?
A.Fatty acid -» Fatty acyl CoA (cytosol)
B.Fatty acyl CoA (cyt)->Fatty acyl Carnitine (mito)
C.Fatty acyl carnitine (mito)-> Fatty acyl CoA (mito)
D.Fatty acyl CoA (mito) ->Fatty enoyl CoA (mito)
B
Your ER patient has a laceration over the distal forearm (over the dorsoradial aspect). Your exam shows that there is no sensation on the dorsum of the hand overlying the 1st dorsal interosseous muscle. You suspect interruption of the
A.superficial branch of the radial nerve. B.dorsal branch of the ulnar nerve. C.median nerve. D.deep branch of the ulnar nerve. E.deep branch of median nerve.
A
Ketone bodies can be used as a fuel by all the following tissues EXCEPT A.brain. B.skeletal muscle. C.heart. D.adipose cells. E.red blood cells.
E
As you sit at your desk, your hand and forearm lie on the desk, palm up. You turn your hand and forearm so that the palm faces down. This movement is referred to as A.flexion. B.hyperextension. C.circumduction. D.circumduction. E.pronation.
E
During fasting, an individual lacking carnitine palmitoyltransferase II would present with all of the following EXCEPT
A.increased levels of fatty acids in the plasma.
B.increased levels of dicarboxylic acids excreted into the urine.
C.increased levels of ketone bodies in the plasma.
D.increased levels of oxidized acylcarnitines excreted into the urine.
E.decreased rate of beta-oxidation in the mitochondria.
C
- A 20- year old male complains that he cannot do strenuous exercise without suffering from muscle cramps and fatigue. He says his urine is often burgundy colored. Otherwise, he appears to be in good health. A defect in carbohydrate metabolism is suspected, but the patient shows no signs of abnormal blood glucose levels, either after a meal or during a fast. Biopsies of liver and muscle showed the glycogen in both tissues to be of normal structure and amount. His exercising forearm was studied by P31 nmr, which is able to measure the levels of ATP, ADP, AMP, and Pi. The intracellular pH can be calculated from the ratio of various ionic forms of phosphate. All the following results are expected EXCEPT which one after intense exercise?
A.Abnormally high ADP B.Abnormally high AMP C.Abnormally high ATP D.Abnormally high Pi E.Abnormally high pH
C
Diabetics and children with inborn errors of fructose and galactose metabolism all suffer from cataracts. The common cause is that the lenses of their eyes have an over-accumulation of
A.the sugar that is not metabolized properly (glucose, fructose, or galactose)
B.the reduced forms of these sugars
C.the oxidized forms of these sugars
D.the phosphorylated forms of these sugars.
B
The first intermediate in glycolysis that has an anhydride bond capable of driving ATP synthesis is A.Glyceraldehyde 3-phosphate B.1,3 bisphosphoglycerate C.Glycerate 3-phosphate D.Glycerate 2-phosphate E.Phosphoenolpyruvate
Answer Key: B
Feedback: All the phosphorylated intermediates up to 1,3 bisphosphoglycerate are phosphoesters, not phosphoanhydrides or mixed anhydrides. A mixed anhydride is one formed from phosphate and a carboxylic acid.
A 37-year-old women died of necrotizing fasciitis, a severe, insidiously advancing, soft-tissue infection, after routine outpatient surgery at a hospital (patient A) A man who was at the same hospital on the same day also developed necrotizing fasciitis but survived (patient B) . On examination of the hospital records, 12 other people over the preceding 16 months who had been treated in the surgical unit were also diagnosed with the infection. The source of the infection was never found.
The organisms isolated from the blood cultures of patient A and Patient B above were Gram positive, beta hemolytic cocci that were catalase negative and bacitracin sensitive. Which ONE of the following best describes the key property of the major virulence determinant of this organism? It
A.binds the Fc region of antibodies directed against it.
B.causes endotoxic shock.
C.causes lysis of red blood cells in vivo.
D.inhibits uptake of the organism by neutrophils
E.promotes coagulation of plasma in vitro.
Answer Key: D
Feedback:
Explanation-case is group A streptococci (by microbiological description and clinical problem of necrotizing fasciitis)
A. is wrong because that describes protein A of Staphylococcus aureus
B. is wrong because endotoxin= LPS; group A streptococci are Gram positive
C. is wrong because hemolysin is not a major virulence determinant of the organism; M protein is the major determinant and is anti-phagocytic (see D)
D. is right because it describes the primary mechanism of virulence of group A streptococci-evasion of uptake by PMNs evoked by M proteins
E. is wrong because coagulase is made by Staphyloccocus aureus, not group A streptococci
Sebaceous glands secrete in what manner?
A.merocrine. B.halocrine. C.paracrine. D.apocrine. E.endocrine.
Answer Key: B
Feedback: Sebaceous glands secrete by halocrine secretion.
A high incidence of skin infections occurred among members of a high school wrestling team. Several of the teenagers were treated with methicillin, but the infections did not resolve. Gram-positive bacteria were isolated from the inflamed skin lesions and bacteria of similar morphology were isolated from the wrestling mats and a tube of taping gel. All of the isolates had the same pattern on pulsed field gel electrophoresis (PFGE) and all were resistant to methicillin. Which of the following events is most likely responsible for methicillin resistance in this organism?
A.Acquistion of a plasmid that encodes ß-lactamase
B.An rRNA gene that underwent spontaneous mutation
C.Integration of a gene that encodes penicillin-binding protein PBP2’ into the chromosome
D.Mutation in a gene that increases the expression of an efflux pump system
E.Spontaneous mutation in the DNA gyrase gene
Answer Key: C
Feedback: Explanation: Based on the description of the organism and its resistance to methicillin the most likely agent is Staphylococcus aureus.
A. is incorrect because methicillin is a semi-synthetic penicillin that is resistant to most bacterial ß-lactamases.
B. is incorrect because the methicillin inhibits cell wall synthesis and does not target ribosomes to inhibit protein synthesis.
C. is the correct response because it is well documented that MRSA have arisen via integration of a sophisticated cassette into the bacterial chromosome that encodes an altered PBP.
D. is incorrect because resistance to methicillin in S. aureus does not occur via increased efflux from the cell via derepression of an active efflux pump system.
E. is in correct because methicillin does not target topoisomerases such as DNA gyrase A to affect transcription and, or replication.
A 4-year-old child presents with multiple vesicular lesions on the mucous membranes of the mouth. These lesions resolve spontaneously with 3 weeks. During the subsequent 12 months, the child suffers several recurrences of blisters around the peri-oral region. In all cases, there is complete recovery followed by symptom-free intervals. The virus responsible for these symptoms A.causes hand-foot-and-mouth disease. B. causes keratitis and encephalitis. C.has a negative-sense RNA genome. D.is transmitted by fecal-oral route. E.replicates in the cytoplasm.
B
Mesissner’s corpuscle is responsive to what type of stimulation?
light touch
Feedback: Encapsulated nerve endings increase the sensitivity and specificity of the nerves for different stimuli. Meissner’s corpuscles are responsive ;low frequency stimuli and are found in the fingertips and toes.
Glucose that is radiolabelled with C14 at the C-1 position was incubated with red blood cells, and the lactic acid excreted by them was collected for analysis. In which carbon atom (s)of lactic acid was the label be found?
A.C-1 only B.C-2 only C.C-3 only D.C-1 and C-3 E.C-1, C-2, and C-3
Answer Key: C
Feedback: correct answer C-3 only
Look at a chart of the pathway that shows the open chain forms of the sugars. The tricky part of this follow-the-label question is to determine which carbon is labeled after the aldolase step. Although it may appear to be the C-1 of dihydroxyacetone phosphate, it is C-3. From there it is easy to follow the label through to lactate.
In muscle, creatine kinase catalyzes the synthesis of creatine phosphate according to the reaction shown below. Given the standard free energy change for hydrolysis of ATP is –7.3 kcal/mol, and for hydrolysis of creatine phosphate is – 10.3 kcal/mol, what is the free energy change of the above reaction starting with 1M reactants and 1M products?
ATP + creatine creatine phosphate + ADP
A.
17.6 kcal/mol
B.
– 10.3 kcal/mol
C.
– 7.3 kcal/mol
D.– 3.0 kcal/mol E.0 kcal/mol F.+ 3.0 kcal/mol G.+ 7.3 kcal/mol H.+ 10.3 kcal/mol I.+ 17.6 kcal/mol
Answer Key: F
The mechanism for the contact dermatitis initiated by contact with nickel is A.type I acute. B.type II cytotoxic antibody mediated. C.type III immune complex mediated. D.type IV delayed cell mediated.
Answer Key: D
Feedback: Antigens activate lymphocytes which activate macrophage to secrete inflammatory molecules.
A single skin lesion that is raised, red, and 1.2cm long by 2.0cm wide is most properly referred to as a A.papule B.bulla C.plaque D.herpetiform eruption
Answer Key: C
Feedback: Correct Answer: C - A plaque is a raised skin lesion larger than 1.0 cm, the color of the lesion does not change the lesion type.
A) is incorrect because a papule is a raised lesion less than 1.0 cm. B) is incorrect because a bulla is filled with clear fluid. D) is incorrect because eruption does not describe a solitary lesion and herpetiform describes the distribution of multiple lesions, not a single lesion.
A 2 year old boy presents with erythema over most of his body. Fluid-filled cutaneous blisters are also present and the skin on his face, shoulders, and arms has undergone desquamation. His mother reports that the boy was fine until a few days earlier, when redness began to develop around his mouth. A diagnosis of scalded skin syndrome is made. The toxin responsible for the observed manifestations of this disease
A.forms immune complexes, which deposit in the skin.
B.induces nonspecific proliferation of helper T cells.
C.promotes unregulated actin polymerization in dermal cells.
D.selectively kills endothelial cells via inhibiting protein synthesis.
E.splits desmosomes in the stratum granulosum epidermis
Answer Key: E
Feedback: Explanation: The toxin that is responsible for scalded skin syndrome is exfoliatin. Answer E is correct because it describes the mechanism of action of exfoliatin. Answers B, C, and D describe the mechanism of action of other bacterial toxins including superantigens in the case of B. Answer A is incorrect because the skin manifestations of scalded skin syndrome are not due to specific antibody forming particulate complexes with exfoliatin or any other bacterial molecule.
A strain of bacteria, E. Gads, ferments glucose to lactate, showing that the enzymes of glycolysis are produced by the organism. It can also ferment glycerol to lactate, but the pathway is not known for sure. Experiments showed that the first step is phosphorylation of glycerol to 3-glycerol phosphate. Researchers then proposed a few possibilities for the second step. Their working assumption was that the organism converts glycerol 3-phosphate to an intermediate in glycolysis, and does so in the fewest possible steps. On this basis, all agreed that the enzyme involved in step 2 is most likely a(n): A.dehydrogenase B.isomerase C.mutase D.aldolase E.enolase
Answer Key: A
Feedback: Glycerol 3-phosphate can be converted to either glyceraldehyde 3-phosphate or dihydroxyacetone phosphate via a dehydrogenase, using NAD+ as the cofactor. The reaction converts hydroxyl groups to carbonyl groups.
Which cell type of the integument is most likely to contain mature pigment granules?
A.Macrophages
B.Fibroblasts of the dermis.
C.Melanocytes
D.Langerhans cells
E.Keratinocytes of the basal and lower spinosus layers.
Answer Key: E
Feedback: The melanocyte produces the melanosomes, the pigment granules. However, as it matures, it is pushed into or phagocytosed by the surrounding keratinocytes of the stratum basale. As these cells move into the stratum spinosus, the melanosomes are retained for a period of time. The melanosomes are lost in the later stages on keratinocyte differentiation.
A patient wants to be treated for their onychomycosis.
Which of the following should be recommended.
A.Topical clotrimazole cream
B.Oral terbinafine
C.Oral penicillin
D.Intravenous amphotericin
E.Surgical excision and amphotericin
Answer Key: B
Feedback: Explanation: Onychomycosis is a fungal infection of the nail which is most often caused by one of the dermatophytes. B is the correct answer because fungal infection of the nail typically requires systemic administration of an antifungal (terbinafine, griseofulvin, or an azole). A is wrong because topical antifungal therapy of onychomycosis is frequently ineffective. C is wrong because penicillin is not an antifungal. While D and E would likely be effective, these choices are not correct because the risk of amphotericin therapy is not typically warranted nor necessary for the treatment of onychomycosis.
Spaghetti and meatballs and the below scenario is associated with what Dx:
A 33 year old woman is seen in clinic with a chief complaint of pink patches on her chest and back. These skin lesions do not itch or hurt. A KOH prep of skin scrapings reveals the following:
The description of pink patches on the skin that do not itch or hurt is consistent with pityriasis versicolor, which is most often caused by Malassezia furfur. The KOH prep reveals the classic “spaghetti and meatballs” appearance of M. furfur, which is due to the circular yeasts and the elongated pseudohyphae.
A 67 year old man visits your clinic complaining of numbness in his toes. Upon examination you discover that the numbness is actually confined to the big toe on his left foot. Based on your knowledge of anatomy, you predict that he may have a compression lesion
A.on the left side of the spine at the level of L5
B.on the right side of the spine at the level of L5
C.on the right side of the spine at the level of C8
D.that is impinging on the coccygeal nerve which causes the numbness
E.on the left side of the spine at the level of C8
Answer Key: A
Feedback:
A compression lesion at L5 could damage the posterior nerve rootlets and impair sensation. Although L5 is also involved in sensation of the lower leg, S1 contributes to that area of the leg as well, so all sensation would not be lost.
C8 is involved in sensation of the forearm and hand.
Coccygeal nerve gives sensation to the skin over the coccyx.
Your preceptor at the simulation center told you about the triangle of auscultation as a good spot to try hear respiratory sounds. In your anatomy dissection of the back, you see that this area is formed by the borders of the
A.The angle created with the neck when the left arm is raised above the head with the elbow flexed at approximately 30 degrees.
B. The transverse processes and the spinous process of the T3 vertebra.
C. Longissimus, illiocostalis, and spinalis muscles.
D. Latissimus dorsi, trapezius and the rhomboid major (medial edge of the scapula).
E.Trapezius, erector spinae, and the splenius capitus
Answer Key: D
Your 12 year old son is studying biology in school and was told that dark-skinned people have “natural sunscreen” that helps prevent sunburn when they are outside in the summer sun. He asks you to explain this and you tell him that it is because people who live in the southern regions of the world have developed
A.Larger and more stable melanosomes.
B.More melanocytes, the cells that produce the dark pigment seen in the skin.
C.A thicker stratum corneum than found in Caucasian skin
D.A different variation of melanin called pheomelanin which is more effective at absorbing ultraviolet rays.
E.Increased turnover in sun-damaged melanin pigment.
Answer Key: A
Feedback: The melanosomes of dark skinned people are larger and more stable than those found light skinned people. Consequently the concentration of melanosomes builds up in cells and melansomes persist through several cell divisions in the stratum spinosum.
The other answers are incorrect statements. Pheomelanin is the yellow-red pigment and is not believed to be particularly effective in protecting against UV rays
