Systemic Health Flashcards
Elastic ligaments which serve to attach bones together are formed from which type of connective tissue?
Dense, irregular connective tissue
Dense, regular connective tissue
Adipose connective tissue
Loose connective tissue
Dense, regular connective tissue
Explanation
Dense, regular connective tissue is composed of parallel bundles of fibers with rows of fibroblasts located between them. Because the fibers are oriented in this manner, they are quite resistant to pulling forces along their axis of orientation and therefore are ideal for supporting other organs and supplying elasticity. This type of connective tissue is generally found in tendons and skin.
Dense, irregular connective tissue is also comprised of fibroblasts and fibers which are pre-dominantly collagen; they do not display structured orientation like dense, regular connective tissue does. This type of tissue protects organs that do not display a lot of stretching.
Loose connective tissue contains many types of cells but lacks an abundance of fibers. The fibers that are present are very loosely arranged. This type of tissue is generally located around blood vessels and nerves as well as organs.
Adipose connective tissue is specialized for storage of fat.
Progressive narrowing of the arterial lumen is BEST known as which of the following terms?
Arteriosclerosis
Arrhythmia
Atherosclerosis
Angina pectoris
Atherosclerosis
Explanation
When excess cholesterol or other lipids build up on the inside of the arterial wall, the lumen of that blood vessel narrows. This narrowing can become aggravated if a platelet becomes stuck on the rough edges of the plaque stimulating a blood clot. The artery may become so clogged that blood flow is impeded and the tissue or organs normally supplied by the vessel may become ischemic. If a coronary artery is affected, chest pains (angina pectoris) or a heart attack may ensue. Atherosclerosis is a type of arteriosclerosis.
Arteriosclerosis results from thickened and hardened arterial walls. Arteriosclerotic blood vessels have lost much of their elasticity.
Arrhythmias are irregular heartbeats. Remember, not all arrhythmias are evil. Endurance athletes can exhibit bradycardia (low cardiac rate).
Which of the following structures serves as a maturation and storage site for sperm?
The vas deferens The testicles The prostate gland The seminiferous tubules The epididymis
The epididymis
Explanation
Sperm are produced by the testicles in the seminiferous tubules and are then transported to the epididymides, where secreted fluids allow them to mature and become fully functional. The sperm are stored here until ejaculation during which the sperm are propelled down the vas deferens, through the ejaculatory ducts and the urethra. The prostate is an accessory gland, along with the seminal vesicles and bulbourethral gland, which help to provide semen and the media necessary for sperm survival.
Rigor mortis occurs due to the inability of myosin cross bridges to detach. What component is DIRECTLY necessary for cross bridge deactivation?
Calcium
Carbon monoxide
Adenosine triphosphate
Troponin
Adenosine triphosphate
Explanation
Upon contraction of a muscle, calcium is released from the sarcoplasmic reticulum (SR). This is a type of modified endoplasmic reticulum that surrounds myofibrils and is responsible for calcium storage and release. Once the calcium is released, it binds to troponin, causing the binding site on the actin filament to become exposed. Actin is then free to bind to myosin, causing muscle contraction. Adenosine triphosphate (ATP) initiates calcium uptake by the SR. In the absence of calcium, the binding site on the actin filament becomes blocked, allowing for muscle relaxation.
When a person dies, ATP ceases to be formed. With the lack of ATP, the myosin cross-bridges cannot detach; this causes constant muscle contraction, or rigor mortis.
Graves’ disease is MOST successfully treated by which of the following means?
Radioactive iodine Levothyroxin Surgical thyroidectomy Propylthiouracil Methimazole Oral corticosteroids
Surgical thyroidectomy
Explanation
The most successful treatment of Graves’ disease has been shown to be a surgical thyroidectomy. There are oral medications that can be used to attempt to treat Graves’ disease, which include propylthiouracil and Thiamazole (methimazole). Another possible treatment option is radioactive iodine therapy; however, it is contraindicated in patients with moderate to severe Graves’ orbitopathy.
Haversian canals are found in which type of tissue?
Brain Muscle Adipose Nervous Bone
Bone
Explanation
Haversian canals are located within compact bone tissue. This type of tissue is organized into small circular layers that form around canals. The canals are connected to one another and house blood vessels and nerves used to maintain osteocytes.
Which 3 of the following blood tests are used in the analysis of liver function? (Select 3)
Glomerular filtration rate (GFR) Bilirubin levels Alkaline phosphatase (ALP) Alanine and aspartate transaminase (ALT & AST) Blood urea nitrogen (BUN) Serum creatinine
Bilirubin levels
Alkaline phosphatase (ALP)
Alanine and aspartate transaminase (ALT & AST)
Explanation
Analysis of certain blood tests can aid in determining whether or not the liver is functioning properly. The most commonly performed blood tests in liver disease include serum bilirubin levels, alkaline phosphatase test, and a measure of alanine and aspartate transaminase levels.
Serum bilirubin levels
- Bilirubin is produced by the liver and excreted in the bile
- Elevated levels of bilirubin in the blood can indicate an obstruction of bile flow or a problem in the production of bile by the liver
Serum alkaline phosphatase levels
- Alkaline phosphatase is an enzyme found in many tissues of the body but in highest concentration in the liver, biliary tract, and bone
- Test used to assess liver function; can be used in the detection of liver lesions that may cause biliary obstruction, such as tumors or abscesses
Alanine and aspartate transaminase levels
- Alanine is an enzyme found predominantly in the liver and is released into the bloodstream after acute damage to liver cells
- Alanine transaminase levels can assess liver function and are used to evaluate treatment effectiveness in acute liver disease (such as hepatitis)
- Aspartate is an enzyme found in the liver, kidneys, pancreas, heart, skeletal muscle and red blood cells
- Aspartate is released into the bloodstream following liver or heart problems
A patient with which of the following laboratory results would be considered diabetic?
Fasting blood glucose of 122 mg/dL
2-hour postprandial glucose of 210 mg/dL
Glycosylated hemoglobin of 6.2%
2-hour postprandial glucose of 210 mg/dL
Explanation
Two-hour postprandial glucose measures the serum level of glucose two hours after a meal. This is commonly measured in pregnant women to assist in the diagnosis of gestational diabetes. In healthy patients, blood glucose levels should normalize within two hours of eating (measured in mg/dL).
Normal 70-141, Pre-diabetes 14-200, diabetes >200
Fasting blood glucose is the amount of glucose in the blood at the time of collection after the patient has refrained from eating or drinking anything but water for at least eight hours (measured in mg/dL).
Normal <100, Pre-diabetes 100-125, diabetes >126
Glycosylated hemoglobin (HbA1c) reflects the percentage of free glucose bound to hemoglobin in red blood cells. Because the average lifespan of a red blood cell is approximately 3 months, this test is a good estimate of the average blood sugar of a patient over that period of time.
Normal 5.7%, pre-diabetes 5.7-6.4%, diabetes >6.5%
Which of the following structures of the ear plays a role in hearing?
Organ of Corti Utricle Saccule Semicircular canals Answer
Organ of Corti
Explanation
The inner ear contains the cochlea. The floor of the cochlear duct houses the basilar membrane, which serves as a bed for the organ of Corti. Hair cells of the organ of Corti protrude upwards onto a membrane called the tectorial membrane. Sound waves cause the fluid in the cochlea to move, which vibrates the basilar membrane. This vibration in turn pushes the hair cells against the tectorial membrane and causes the hair cells to bend. The bent hair cells release a neurotransmitter, resulting in action potentials of the auditory nerve.
The semicircular canals are a part of the vestibular apparatus along with the utricle and saccule. The semicircular canals are positioned at right angles to each other and help to code for acceleration, deceleration, and rotational head movements (angular acceleration). The semicircular canals are filled with fluid (endolymph). At the base of the canals are the ampullae that rest atop specialized hair cells that bend in response to the movement of fluid, allowing for processing by the brain.
The utricle and the saccule are sac-like, filled with fluid, and help to detect linear acceleration. These structures contain small calcium carbonate stones called otoliths. Each sac contains hair cells embedded in a jelly-like mass along with the otoliths. Movements of the mass and the otoliths signal a change in position of the head or body. Movement at constant speed will not be detected by these structures because the otoliths eventually come to equilibrium.
In general, most of the water that we ingest largely ends up in which of the following states?
Reabsorbed in the blood
Waste excreted by the kidneys
Secreted out of our pores as sweat
Excreted during respiration
Reabsorbed in the blood
Explanation
In a healthy individual with normal kidney function, the majority of ingested water is reabsorbed and returned to the blood. Roughly 1% of water that is taken in becomes excreted by the body. The composition and concentration of the water that is not retained is altered accordingly based upon the body’s needs.
You are reviewing a lipid panel that was ordered for a 32-year-old patient with significant corneal arcus. Which of the following values would be considered “high?”
LDL lipoproteins: 120 mg/dL
Total cholesterol: 250 mg/dL
HDL lipoproteins: 50 mg/dL
Triglycerides: 200 mg/dL
Total cholesterol: 250 mg/dL
Explanation
Total cholesterol, when used alone, is an insufficient indicator for the diagnosis and treatment of dyslipidemia; however, it can be helpful when used with other data to asses a patient’s risk for heart disease.
Desirable: <200 mg/dL, borderline high: 200-239 mg/dL, high: >240 mg/dL
Low-density lipoproteins (LDLs) are known as “bad” cholesterol as they bind to arteries and increase a person’s risk for diseases such as hypertension and atherosclerosis.
Optimal: <100 mg/dL, near optimal: 100-129 mg/dL, borderline high: 130-159 mg/dL, high: >160 mg/dL
High-density lipoproteins (HDLs) are known as the “good” cholesterol. They are considered cardioprotective as they remove cholesterol from the arteries and transport it back to the liver.
Low: <40 mg/dL, high: > or = 60mg/dL
Triglycerides can be particularly high due to physical inactivity, smoking, obesity, and high-carbohydrate diet. High triglycerides also increase the risk for cardiovascular disease.
Optimal: <150 mg/dL, near optimal: 150-199 mg/dL, borderline high: 200-499 mg/dL, high: >500 mg/dL
The head of human sperm possesses a cap-containing enzyme that helps penetrate the female gamete. What is the name of this cap?
The capsomere
The Sertoli cell
Lysozyme
The acrosome
The acrosome
Explanation
The human male sperm is comprised of a head, a mid-piece, and a tail. The head contains DNA as well as a cap-containing enzyme called an acrosome that helps the sperm to penetrate the egg for fertilization. The mid-piece is rich in mitochondria and serves to give the sperm energy in order for the tail to propel it to the egg. Sertoli cells line the seminiferous tubules and secrete chemicals as well as offer nourishment to developing sperm in the testicles. Lysozyme is found in many bodily secretions such as tears and saliva and is an immune-defensive mechanism used to destroy unwanted bacteria.
Where is the sinoatrial node of the heart located?
The upper left atrium
The upper right atrium
The lower right ventricle
The lower left ventricle
The upper right atrium
Explanation
Think in terms of function to help determine and remember the answer to this question. The first area to contract is the right atrium (only briefly, before the left atrium). Logically, it therefore would make sense for the pacemaker of the heart to be located at the site of contraction origin. The atria contract first, followed by contraction of the ventricles.
Homocysteine levels can be reduced by which of the following vitamins?
Vitamins A and D
B vitamins
Vitamin C
Vitamin E
B vitamins
Explanation
The B vitamins, B12, B6, and folic acid (also known as B9) can reduce homocysteine levels. The other vitamins have no impact on homocysteine. Homocysteine is a metabolic product of the metabolism of methionine. It is associated with premature atherosclerosis and thrombotic complications such as thrombophlebitis. There is great excitement in the medical community about the ability of B vitamins to reduce homocysteine levels; they have been found to do so in multiple studies. Unfortunately, a reduction in cardiovascular disease has not occurred as a consequence of the reduction in this risk factor. It is probably appropriate to maintain homocysteine within a healthy range by restricting foods that are high in methionine and by maintaining an adequate supply of these B Vitamins.
Which of the following types of headaches is characterized by the presence of a severe unilateral headache with periocular pain and an ipsilateral Horner syndrome?
Raeder's paratrigeminal neuralgia Cluster headache Ophthalmoplegic migraine Tension headache Ice-pick syndrome
Raeder’s paratrigeminal neuralgia
Explanation
Raeder’s paratrigeminal neuralgia is a severe unilateral headache with periocular pain that follows the first distribution of the trigeminal nerve. In addition to the headache, these patients will also present with an ipsilateral Horner’s syndrome. These symptoms may last from hours to weeks but will eventually resolve spontaneously.
Ice-pick syndrome is characterized by multifocal, sharp, quick, intense pains that occur around the areas of the skull, face, and eyes. This can be differentiated from trigeminal neuralgia in that pain in these cases does not follow the anatomical distribution of the trigeminal nerve.
Ophthalmoplegic migraines usually occur in patients under the age of 10. It is characterized by a recurrent, transient third nerve palsy, which develops after the headache.
Cluster headaches are typically unilateral and oculotemporal in location, associated with deep, sharp, excruciating pain that may last 10 minutes to 2 hours. These headaches will typically occur on a daily basis for a period of several weeks; thus the name “cluster.”
Tension headaches are the most common type of primary headache in adults. The pain in these headaches usually radiates from the lower back of the head, the neck, or the eyes. The pain is commonly bilateral and is usually mild to moderate but can be severe in some patients.
Which of the following neuromuscular disorders affecting extraocular muscle movements develops as a result of abnormalities in the DNA of mitochondria?
Myotonic dystrophy
Ocular myasthenia gravis
Grave’s ophthalmopathy
Kearns-Sayre syndrome
Kearns-Sayre syndrome
Explanation
Kearns-Sayre syndrome is considered a mitochondrial myopathy in which mitochondrial DNA deletions result in a clinical triad of signs. These signs include ocular features such as progressive external ophthalmoplegia (CPEO) and “salt and pepper” pigmented retinopathy (with predilection for the macula), as well as one or more systemic complications, which can include heart block, cerebellar ataxia, or abnormally elevated cerebrospinal fluid protein.
Grave’s ophthalmopathy occurs as a result of an autoimmune disease that results in thickening of the extraocular muscles.
Ocular myasthenia gravis is also an autoimmune disease that causes weakness of the extraocular muscles and levator palpebrae superioris.
Myotonic dystrophy is caused by mutations of the DMPK gene (type 1) and CNBP gene (type 2). Extraocular muscle symptoms of this type of disease include rebound nystagmus, saccadic dysfunctions, and optokinetic nystagmus.
