MOSBY Flashcards
Nonsteroidal anti-inflammatory agents are pain relieving and anti-inflammatory. They are effective since they act to inhibit prostaglandin synthesis by:
A. Inhibiting fatty acid lipo oxygenase activity.
B. Inhibiting fatty acid-specific cyclo-oxygenase activity.
C. Inhibiting fatty acid-specific hydroperoxidase activity.
D. Inhibiting phospholipase A2
.
B. Inhibiting fatty acid-specific cyclo-oxygenase activity.
The synthesis of all steroid hormones involves which of the following compounds?
A. Pregnenolone.
B. Progesterone.
C. Aldosterone.
D. Cortisone.
E. Testosterone
A. Pregnenolone.
Lipid micelles are stabilized by which of the following?
A. Hydrophobic interactions.
B. Hydrophilic interactions.
C. Interactions of lipid and water.
D. Interaction of hydrophobic lipid tails with hydrophobic domains of proteins.
A. Hydrophobic interactions.
Which one of the following carbohydrates is a ketose sugar?
A. Galactose.
B. Fructose.
C. Glucose.
D. Mannose.
E. Glyceraldehydes.
B. Fructose.
ALDOSES
Galactose
Glucose
Mannose
Glyceraldehydes
Mucopolysaccharidoses are hereditary disorders that are characterized by the accumulation of glycosaminoglycans in various tissues due to which of the following?
A. Overproduction (synthesis) of proteoglycans.
B. Deficiency of one of the lysosomal, hydrolytic enzymes normally involved in the degradation of one or more of the glycosaminoglycans.
C. The synthesis of abnormal proteoglycans.
D. The synthesis of highly branched glycosaminoglycan chains
B. Deficiency of one of the lysosomal, hydrolytic enzymes normally involved in the degradation of one or more of the glycosaminoglycans.
Hydrolysis of which of the following compounds yields urea?
A. Ornithine.
B. Argininosuccinate.
C. Aspartate.
D. Citrulline.
E. Arginine.
E. Arginine.
The binding of epinephrine or glucagon to the corresponding membrane receptor has which of the following effects on glycogen metabolism?
A. The net synthesis of glycogen is increased.
B. Glycogen phosphorylase is activated while glycogen synthase is inactivated.
C. Glycogen phosphorylase is inactivated while glycogen synthase is activated.
D. Both glycogen synthase and phosphorylase are activated.
E. Both glycogen synthase and phosphorylase are inactivated.
B. Glycogen phosphorylase is activated while glycogen synthase is inactivated.
When an enzyme is competitively inhibited, which of the following changes occur?
A. The apparent Km is unchanged.
B. The apparent Km is decreased.
C. Vmax is decreased.
D. Vmax is unchanged.
D. Vmax is unchanged.
Which compound is produced in the hexose monophosphate (pentose phosphate) pathway?
A. ATP.
B. NADH.
C. NADPH.
D. Fructose 1,6-bisphosphate.
E. Phosphoenolpyruvate.
C. NADPH.
During exercise, which of the following is decreased?
A. Oxidation of fatty acids.
B. Glucagon release.
C. Glycogenolysis.
D. Lipogenesis.
D. Lipogenesis.
Increased formation of ketone bodies during fasting is a result of which of the following?
A. Increased oxidation of fatty acids as a source of fuel.
B. Decreased formation of acetyl CoA in the liver.
C. Decreased levels of glucagon.
D. Increased glycogenesis in muscle.
A. Increased oxidation of fatty acids as a source of fuel.
Which of the following enzymes found in the liver is involved in gluconeogenesis during the postabsorptive state?
A. Glucose 6-phosphate dehydrogenase.
B. 6-phosphogluconate dehydrogenase.
C. Glucose 6-phosphatase.
D. Glucokinase.
B. 6-phosphogluconate dehydrogenase.
In which one of the following tissues is glucose transport into the cell unaffected by insulin?
A. Skeletal muscle.
B. Liver.
C. Adipose tissue.
D. Smooth muscle.
B. Liver.
Which of the following genetic diseases that results from a deficiency in the liver enzyme that converts phenylalanine to tyrosine?
A. Albinism.
B. Homocystinuria.
C. Porphyria.
D. Phenylketonuria.
D. Phenylketonuria.
If the molar percentage of guanine in a human DNA is 30%, what is the molar percentage of adenine in that molecule?
A. 10%.
B. 20%.
C. 30%.
D. 40%.
E. 50%.
B. 20%
DNA
AT = 20 + 20
GC = 30 + 30
Which of the following phrases best describes restriction enzymes?
A. Site-specific endonucleases.
B. Enzymes that regulate RNA.
C. Nonspecific endonucleases.
D. Topoisomerases.
A. Site-specific endonucleases.
The coenzyme that serves as an intermediate carrier of one-carbon units in the synthesis of nucleic acids is which of the following?
A. Ascorbic acid.
B. Tetrahydrofolic acid.
C. Biotin.
D. Pyridoxine.
B. Tetrahydrofolic acid.
Following the production of Okazaki fragments, which of the following is required to close the gap between the fragments?
A. DNA ligase.
B. DNA polymerase.
C. RNA polymerase.
D. Reverse transcriptase.
A. DNA ligase.
Which of the following is not involved in the process of gene cloning?
A. DNA polymerase.
B. DNA ligase.
C. RNA polymerase.
D. Restriction endonuclease
C. RNA polymerase.
Vitamin K serves as a coenzyme for:
A. The enzymatic hydroxylation of proline to 4-hydroxyproline.
B. The carboxylation of inactive prothrombin to form active prothrombin.
C. The synthesis of nucleic acids.
D. Protein synthesis.
B. The carboxylation of inactive prothrombin to form active prothrombin.
Chondroitin sulfate is a major component of which of the following?
A. Bacterial cell walls.
B. Mucin.
C. IgA.
D. Cartilage.
E. Hair.
D. Cartilage.
Which of the following amino acids is positioned at every third residue in the primary structure of the helical portion of the collagen-a chains?
A. Glycine.
B. Glutamate.
C. Proline.
D. Lysine.
E. Hydroxyproline.
A. Glycine.
Which of the following is not involved in the process of mineralization?
A. Matrix vesicles.
B. Amelogenins.
C. Fluoride.
D. Phosphoryns.
C. Fluoride.
ATP is utilized directly for each of the following processes except:
A. Accumulation of Ca2+ by the sarcoplasmic reticulum.
B. Transport of Na+ from intracellular to extracellular fluid.
C. Transport of K+ from extracellular to intracellular fluid.
D. Transport of H+ from parietal cells into the lumen of the stomach.
E. Transport of glucose into muscle cells.
E. Transport of glucose into muscle cells.
Both active transport and facilitated diffusion are characterized by which of the following?
A. Transport in one direction only.
B. Hydrolysis of ATP.
C. Transport against a concentration gradient.
D. Competitive inhibition.
D. Competitive inhibition.
Which of the following statements regarding the autonomic nervous system (ANS) is true?
A. The third cranial nerve (the oculomotor nerve) carries sympathetic fibers to the smooth muscles of the eye.
B. The facial and the glossopharyngeal cranial nerves carry the parasympathetic preganglionic fibers for the autonomic innervation to the salivary glands.
C. The parasympathetic nervous system innervates primarily striated muscle in the body.
D. The parasympathetic nervous system is organized for diffuse activation and responses.
B. The facial and the glossopharyngeal cranial nerves carry the parasympathetic preganglionic fibers for the autonomic innervation to the salivary glands.
Which of the following responses is due to the stimulation of α-adrenergic receptors?
A. Slowing of heart rate.
B. Constriction of blood vessels in skin.
C. Increased gastrointestinal motility.
D. Increased renal blood flow.
B. Constriction of blood vessels in skin.
Which of the following is a property of C fibers?
A. Have the slowest conduction velocity of any nerve fiber type.
B. Have the largest diameter of any nerve fiber type.
C. Are afferent nerves from muscle spindles.
D. Are afferent nerves from Golgi tendon organs.
E. Are preganglionic autonomic fibers.
A. Have the slowest conduction velocity of any nerve fiber type.
The participation of calcium in the contraction of skeletal muscle is facilitated or associated with which of the following?
A. Calcium release from sarcoplasmic reticulum.
B. Calcium binding to the myosin heads.
C. Active transport of calcium out of longitudinal tubules.
D. Uptake of calcium by T-tubules.
A. Calcium release from sarcoplasmic reticulum.
Calcium that enters the cell during smooth muscle excitation binds with which of the following?
A. Calmodulin.
B. Inactive myosin kinase.
C. Troponin.
D. Myosin.
E. Actin
A. Calmodulin.
Which of the following does not affect the muscle tension produced during contraction?
A. The extent of motor-unit recruitment.
B. The proportion of each single motor unit that is stimulated to contract.
C. The number of muscle fibers contracting.
D. The frequency of stimulation.
B. The proportion of each single motor unit that is stimulated to contract.
The pressure in a capillary in skeletal muscle is 37 mmHg at the arteriolar end and 16 mmHg at the venular end. The interstitial pressure is 0 mmHg. The colloid osmotic pressure is 26 mmHg in the capillary and 1 mmHg in the interstitial fluid. The net force producing fluid movement across the capillary wall is which of the following ?
A. 1 mmHg out of the capillary.
B. 3 mmHg out of the capillary.
C. 12 mmHg out of the capillary.
D. 3 mmHg into the capillary.
B. 3 mmHg out of the capillary.
A patient has a heart rate of 70 bpm. Her EDV (end-diastolic volume) is 140 mL. Her ESV (end systolic volume) is 30 mL. Calculate the CO (cardiac output) of this individual.
A. 9800 mL.
B. 2100 mL.
C. 7700 mL.
D. 15,400 mL
C. 7700 mL.
CO= (EDV-ESV) X heart rate
= (140-30) X 70
= 110 X 70
= 7700 mL
The velocity of blood flow _____.
A. Is higher in the capillaries than the arterioles
B. Is higher in the veins than in the venules
C. Is higher in the veins than in the arteries
D. Falls to zero in the descending aorta during diastole
B. Is higher in the veins than in the venules
Which of the following does not occur to compensate for a fall in blood pressure below normal values?
A. Increased cardiac output.
B. Increased stroke volume.
C. Increased heart rate.
D. Decreased total peripheral resistance.
D. Decreased total peripheral resistance.
CO2 generated in the tissues is carried in venous blood primarily in which form?
A. CO2 in the plasma.
B. H2 CO3 in the plasma.
C. HCO3 in the plasma.
D. CO2 in the red blood cells.
E. Carboxyhemoglobin in the red blood cells.
D. CO2 in the red blood cells.
Which of the following is the most significant stimulant of the respiratory center?
A. Decreased blood oxygen tension.
B. Increased blood hydrogen ion concentration.
C. Decreased blood hydrogen ion concentration.
D. Increased blood carbon dioxide tension.
D. Increased blood carbon dioxide tension.
The primary factor determining the percent of hemoglobin saturation is:
A. Blood PO2
B. Blood PCO2
C. Diphosphoglycerate concentration.
D. The temperature of the blood.
E. The acidity of the blood.
A. Blood PO2
For which of the following substances would you expect the renal clearance to be the lowest, under normal conditions?
A. Urea.
B. Creatinine.
C. Sodium.
D. Water.
E. Glucose.
E. Glucose.
The process of active sodium transport in the ascending limb of the loop of Henle is absolutely essential for which of the following processes?
A. Regulation of chloride excretion.
B. Regulation of pH in extracellular fluid.
C. Regulation of aldosterone excretion.
D. Regulation of water excretion.
D. Regulation of water excretion.
Hypertension (long-term) will be compensated by which of the following renal mechanisms?
A. Increased circulating ADH (vasopressin).
B. Increased sympathetic activity.
C. Decreased circulating aldosterone.
D. Increased circulating angiotensin II.
C. Decreased circulating aldosterone.
Which of the following statements regarding tubular secretion in the kidney is true?
A. The secretion of K+ increases when a person is in acidosis.
B. The secretion of H+ increases when a person is in alkalosis.
C. It is a process that transports substances from the filtrate to the capillary blood.
D. It accounts for most of the K+ in the urine.
D. It accounts for most of the K+ in the urine.
Which of the following statements regarding salivary secretion is true?
A. In general, saliva is more hypertonic than plasma.
B. As salivary flow increases, bicarbonate concentration decreases.
C. As salivary flow increases, ionic concentration increases.
D. Salivary secretion is regulated primarily by hormonal stimulation.
C. As salivary flow increases, ionic concentration increases.
Which of the following is the predominant immunoglobulin in whole saliva?
A. Secretory IgA.
B. Secretory IgG.
C. Secretory IgM.
D. Secretory IgB.
A. Secretory IgA.
The pancreas produces enzymes that are responsible for the digestion of dietary compounds. Which of the following foods would not be digested by enzymes synthesized and secreted by the pancreas?
A. Carbohydrates.
B. Lipids.
C. Vitamins.
D. Protein.
C. Vitamins.
Which of the following statements regarding the hormone secretin is true?
A. It is responsible for activating chymotrypsinogen.
B. It stimulates the release of pancreatic secretion rich in bicarbonate.
C. It stimulates the release of pancreatic enzymes.
D. It stimulates the contraction of the gallbladder to release bile.
B. It stimulates the release of pancreatic secretion rich in bicarbonate.
Phospholipase C is an enzyme that plays an important role in the production of second messengers, which produce intracellular responses. Which two second messengers are produced through the action of this enzyme?
A. cAMP and tyrosine kinase.
B. Acetylcholine and histidine.
C. Adenylate cyclase and protein kinase.
D. 1,2-diacylglycerol and inositol 1,4, 5 trisphosphate.
D. 1,2-diacylglycerol and inositol 1,4, 5 trisphosphate.
Hormones secreted by the posterior pituitary gland include which of the following?
A. Prolactin.
B. Follicle-stimulating hormone.
C. Luteinizing hormone.
D. Vasopressin.
D. Vasopressin.