Vander’s Human Physiology 14th Edition

1. Which of the following is NOT primarily a function of blood plasma? A. transport of hormones B. being in osmotic balance with red blood cells C. having plasma proteins that exert an osmotic pressure favoring fluid absorption into the capillaries D. providing clotting factors that are ready to be activated E. transport of oxygen - correct answer e 2. Which of the following does NOT describe erythrocytes? A. contain myoglobin B. have a high surface-to-volume ratio C. carry oxygen and carbon dioxide in blood D. are red in color E. when mature, have no nucleus - correct answer a 3. What is the term that describes the production of red blood cells? A. hemaglutination B. erythrocytosis C. erythropoiesis D. erythroblastosis E. hemostasis - correct answer c 4. Which is TRUE about the condition anema? A. It can be caused by too little iron in the diet. B. It can be caused by kidney failure. C. It can be caused by abnormal hemoglobin. D. It results in reduced oxygen-carrying capacity of the blood. E. All of the above are true. - correct answer e 5. A female patient has a blood test. One ml of her blood is drawn, spun in a centrifuge, and the plasma volume is measured and found to be 0.6 ml. Two months later the same patient returns to the doctor and, after doing another blood test, the doctor tells the patient that she has become anemic compared to her previous visit. Which of the following is most likely to be the woman's hematocrit on the second visit? A. 35% B. 50% C. 70% D. 100% E. 0.6 ml - correct answer a 6. A male patient complains of physical weakness and fatigue. A blood test shows his hematocrit to be 30%. Which of the following diagnoses is the least likely to explain his symptoms? A. internal bleeding B. dietary iron deficiency C. dietary vitamin B12 deficiency D. lung disease E. kidney disease - correct answer d 7. Where is most of the iron in a person's body located? A. in the bone marrow B. in the liver C. in the cytochromes D. in erythrocytes E. in the kidneys - correct answer d 8. Deficiency of which of the following results in the condition, pernicious anemia? A. iron B. vitamin B12 C. erythropoietin D. vitamin D E. bilirubin - correct answer b 9. Consider the equation F = P/R. It describes the flow (F) of fluid in a tube in which there is a pressure difference (P) between the two ends and a resistance (R) to flow. Based on this equation, which is a correct conclustion? A. The flow of fluid in a tube depends upon the absolute pressure at the beginning of the tube. B. The rate of fluid flow in a tube will increase if the pressure at the beginning is increased while the pressure at the end of the tube stays the same. C. The greater the resistance to flow in a tube, the greater the rate of flow for any given pressure difference. D. If both the resistance and the pressure gradient in a tube increase, the flow must also increase. E. The rate of flow in a tube will decrease if the resistance to flow is decreased. - correct answer b 10. Which of the following changes would most increase the resistance to blood flow in a blood vessel? A. halving the diameter of the vessel B. doubling the diameter of the vessel C. halving the length of the vessel D. doubling the length of the vessel E. decreasing the hematocrit from 50% to 40% - correct answer a 11. Action potentials in the heart spread from cell to cell through: A. desmosomes. B. gap junctions. C. interneurons. D. valves. E. coronary vessels. - correct answer b 12. The pacemaker of the heart is normally what structure? A. sinoatrial node B. atrioventricular node C. mitral valve D. bundle of His E. left ventricle - correct answer a 13. Which is correct about the contraction sequence of the heart? A. The contraction and relaxation of of all four chambers happen at the same time. B. The right atrium and ventricle contract at the same time, and as they are relaxing the left atrium and left ventricle begin to contract. C. Contraction begins in this order: right atrium then right ventricle then left atrium then left ventricle. D. The two atria contract at the same time, and as they are relaxing, the two ventricles contract together. E. The atria and ventricles begin their contractions at the exact same time, but the atrial contraction only lasts half as long as the ventricle contraction. - correct answer d 14. Which of the following statements concerning the differences between action potentials in skeletal muscle cells and in ventricular cardiac muscle cells is TRUE? A. Like skeletal-muscle cells, ventricular cardiac-muscle cells have a resting membrane potential closer to the sodium equilibrium potential than to the potassium equilibrium potential. B. Unlike skeletal-muscle cells, the initial depolarization of ventricular cells is mainly due to calcium influx, not sodium influx. C. After sodium influx through voltage-gated channels occurs in ventricular cells, a prolonged influx of calcium occurs. No such calcium influx occurs in skeletal muscle cells. D. Action potentials in skeletal muscle cells are longer in duration than action potentials in cardiac muscle cells. E. The efflux of K+ repolarizes skeletal muscle cells after an action potential, while repolarization in cardiac muscle cells is due to the efflux of Ca2+. - correct answer c 15. Which of the following statements is true concerning the diastolic depolarization phase of a cell in the SA node? A. The cell will not depolarize until it receives sympathetic stimulation. B. The pacemaker potential is caused by Ca2+ entering the cell via L-type Ca2+ channels. C. The pacemaker potential is slower in achieving threshold when acetylcholine is applied to the SA node cells. D. During diastolic depolarization, there is a gradually increasing permeability to K+. E. The slope of the diastolic depolarization is decreased when norepinephrine is applied to the SA node cells. - correct answer c 16. Which would NOT occur as a result of the blockage of action potential propagation through the bundle of His? A. There would be a slowing of the frequency of contraction of the ventricles. B. The atria would contract more frequently than the ventricles. C. The SA node would no longer set the pace for atrial contraction. D. The atria and ventricles would no longer beat in synchrony. E. The Purkinje fibers would not receive their typical action potentials from the bundle branches. - correct answer c 17. The plateau of the action potential in cardiac ventricular cells results from the opening of voltage-gated long-lasting ___________ channels in the plasma membrane of the cell. A. Na+ B. K+ C. Ca2+ D. Cl- E. glucose - correct answer c 18. Which of the following statements about membrane potentials in different types of cardiac cells is TRUE? A. Myocardial cells have a resting membrane potential of about -90 mV; pacemaker cells do not have a true resting membrane potential. B. Once threshold depolarization is reached in both myocardial and pacemaker cells, the rapid upswing of the action potential is caused by the opening of voltage-gated Na+ channels C. Voltage-gated transient (T-type) Ca2+ channels are present in all of the different types of cells of the heart. D. There are no L-type Ca2+ channels in cardiac muscle cells. E. The upstroke of the action potential is steeper in SA node cells than it is in Purkinje cells. - correct answer a 19. What best represents the QRS complex in an electrocardiogram? A. depolarization of the atria B. repolarization of the atria C. depolarization of the ventricles D. repolarization of the ventricles E. the delay at the AV node - correct answer c 20. Which of the following would be most likely to be determined with a patient's ECG recording? A. a heart murmur B. stroke volume C. cardiac output D. blockage of conduction of electrical signals between the atria and the ventricles E. a leaky atrioventricular valve - correct answer d 21. Which is TRUE about the comparison of excitation-contraction coupling in cardiac muscle with that in skeletal muscle? A. Extracellular Ca2+ plays a major role in cardiac but not skeletal muscle. B. The mechanism for Ca2+ release from the sarcoplasmic reticulum is the same in both types of muscle. C. Troponin sites are completely saturated immediately after Ca2+ release in both types of muscle. D. There is no net change in total intracellular Ca2+ concentration in either muscle. E. Intracellular Ca2+ stores are necessary for contraction in skeletal muscle, but not in cardiac muscle. - correct answer a 22. Which of the following statements about the absolute refractory period of cardiac muscle cells is TRUE? A. It lasts for the same length of time in cardiac muscle cells as it does in skeletal muscle cells. B. It is much longer than the refractory period of skeletal muscle cells. C. It allows for tetanic contractions of the heart to occur to assure smooth, coordinated ejection of blood from the ventricles. D. Ventricular muscle cells are in the absolute refractory period from the beginning of contraction until the beginning of their next contraction. E. During the absolute refractory period, a larger-than-normal stimulus will result in a premature ventricular contraction. - correct answer b 23. Which of the following statements about the refractory period of neuronal or muscle membranes is TRUE? A. In nerve cells, the absolute refractory period coincides with the period of increased K+ permeability. B. In skeletal-muscle cells, the absolute refractory period lasts about as long as the twitch. C. In ventricular cells, the absolute refractory period coincides with the period of increased Na+ and Ca2+ permeability. D. The relative refractory period in neuronal membranes lasts about the same length of time as the absolute refractory period in cardiac muscle cell membranes. E. The refractory period in an alpha-motor neuron membrane is much briefer than the refractory period in a skeletal muscle cell membrane. - correct answer c 24. Which of the following statements about the cardiac cycle is true? A. The duration of systole is greater than that of diastole. B. During isovolumetric ventricular relaxation, blood flows from the atria into the ventricles. C. Closure of the atrioventricular valves occurs at the onset of ventricular systole. D. The QRS complex occurs at approximately the same time as the closure of the semilunar valves. E. The first valves to go from closed to open after the atrial kick are the atrioventricular valves. - correct answer c 25. Which of the following statements regarding the cardiac cycle is TRUE? A. The AV valves are open during mid-to-late diastole. B. The aortic valve is open during isovolumetric ventricular contraction. C. The first heart sound is caused by the closing of the semilunar valves. D. The dicrotic notch is a result of closure of the AV valves. E. Closure of the AV valves occurs when the ventricles reach end-systolic volume. - correct answer a 26. During the cardiac cycle: A. the volume of blood leaving the left side of the heart is greater than that leaving the right side. B. the pressure of blood leaving the right ventricle is greater than that leaving the left ventricle. C. the duration of systole is greater than that of diastole. D. the duration of diastole is greater than that of systole. E. the contraction of the atria overlaps in time with with ventricular systole. - correct answer d 27. Which is TRUE about the function of the aortic valve? A. It prevents the backflow of blood into the aorta during ventricular diastole. B. It prevents the backflow of blood into the left ventricle during ventricular diastole. C. It prevents the backflow of blood into the left ventricle during ventricular ejection. D. It prevents the backflow of blood into the aorta during ventricular ejection. E. Its closure causes the first heart sound. - correct answer b 28. Which occurs during isovolumetric ventricular contraction? A. Rapid filling of the ventricles occurs. B. No blood enters or leaves the ventricles. C. The maximum volume of blood is ejected. D. Ventricular pressure reaches its maximum value of the cardiac cycle. E. The pressure in the ventricles decreases while the pressure in the atria increases. - correct answer b 29. What causes the opening and closing of the heart valves? A. stimulation by the sympathetic and parasympathetic nerves B. a pressure difference on the two sides of the valve C. Na+ and K+ fluxes during ventricular depolarization D. turbulent flow in the atria and ventricles E. the action of the papillary muscles and chordae tendineae - correct answer b 30. What is indicated by a heart murmur detected between the first and second heart sounds? A. insufficiency of a semilunar valve or stenosis of an AV valve B. insufficiency of an AV valve or stenosis of a semilunar valve C. heart failure D. AV nodal conduction block E. a myocardial infarction - correct answer b 31. Which best defines the cardiac output? A. the end-diastolic volume minus the end-systolic volume B. the output of the aortic arch baroreceptors C. the volume of blood in the arterial tree at any moment in time D. the stroke volume divided by the heart rate E. the product of the heart rate and the volume ejected from the ventricle during a cardiac cycle - correct answer e 32. Sinoatrial node cells: A. reach threshold only when action potentials generated by the AV node arrive through gap junctions. B. exhibit spontaneous depolarization that is speeded by activation of their cholinergic receptors. C. exhibit spontaneous depolarization that is speeded by activation of their beta-adrenergic receptors. D. exhibit a steep upstroke due to the presence of the same type of Na+ channels found in neuronal membranes. E. are in-between atrial muscle cells and cells of the bundle of His. - correct answer c 33. Which is TRUE regarding the regulation of heart rate? A. Stimulation of parasympathetic nerves to the heart causes a slowing of heart rate. B. Stimulation of sympathetic nerves to the heart causes an increase in heart rate. C. A person whose heart lacks autonomic innervation has a faster heart rate at rest than a person with a normally innervated heart. D. The slope of diastolic depolarization in SA node cell action potentials determines the heart rate. E. All of the choices are true. - correct answer e 34. The frequency of action potentials generated by the SA node is: A. increased by parasympathetic stimulation. B. decreased by sympathetic stimulation. C. increased by acetylcholine. D. increased by epinephrine. E. increased by an increase in blood pressure. - correct answer d 35. What is described by the Frank-Starling mechanism of the heart? A. the relationship between end-diastolic volume and heart rate - correct answer B. the relationship between end-systolic volume and stroke volume