Sherwood Ch 7 Multi-choice, Sherwood Ch 8 Multi-choice, Ch 10 Sherwood, Sherwood Ch 9 MC

23. If the arterial blood pressure is recorded at 132/84, what is the mean arterial pressure? a. 100 mm Hg b. 93 mm Hg c. 108 mm Hg d. 48 mm Hg e. none of these

ANS: A PTS: 1 DIF: Analysis

57. Given the following forces acting at a given point across the capillary wall, _______ will occur with a net ______ pressure of ____ mm Hg. - capillary blood pressure = 32 mm Hg - blood osmotic pressure = 23 mm Hg - interstitial fluid hydrostatic pressure = 1 mm Hg - interstitial fluid osmotic pressure = 0 mm Hg a. Ultrafiltration, outward, 8 b. Ultrafiltration, outward, 10 c. Ultrafiltration, outward, 56 d. Reabsorption, inward, 24 e. Reabsorption, inward, 10

ANS: A PTS: 1 DIF: Analysis

100. Which statement is incorrect about smooth muscle? a. It develops less tension per unit cross-sectional area compared to skeletal muscle. b. It can maintain tension with comparatively less ATP consumption than skeletal muscle. c. It lacks troponin. d. The range of lengths over which it can develop near maximal tension is greater than for skeletal muscle. e. In the walls of a hollow organ it can accommodate variable volumes with little change in the pressure exerted on the organ's contents.

ANS: A PTS: 1 DIF: Comprehension

105. Considering muscles, bones, and joints as lever systems, a calculated "moment" for the load would be a. force times load arm b. force times power arm c. load arm divided by force d. either a and b e. either b and c

ANS: A PTS: 1 DIF: Comprehension

12. Which of the following factors would produce the greatest change in blood flow? a. Doubling the radius of the vessel b. Doubling the difference in the pressure gradient within the vessel c. Doubling the viscosity of the blood d. Doubling the length of the vessel e. Halving the viscosity of the blood

ANS: A PTS: 1 DIF: Comprehension

16. The arteries a. serve as rapid-transit passageways from the heart because of their large radii b. act as a blood reservoir because they have the capacity to store large volumes of blood with little change in their internal pressure c. are the major sites of blood flow resistance in the vasculature d. are the site of exchange between the blood and surrounding tissues e. always carry oxygenated blood

ANS: A PTS: 1 DIF: Comprehension

27. Which of the following events occurs after all the other steps listed when describing the stimulation of a skeletal muscle fiber? a. ACh binds with receptors on the muscle cell membrane, opening sodium channels. b. ACh diffuses across the cleft of the junction. c. ACh is released by exocytosis. d. Calcium diffuses into the terminal button. e. Voltage-gated channels for calcium in the axon terminal are opened.

ANS: A PTS: 1 DIF: Comprehension

28. Which is the normal sequence of the spread of cardiac excitation? 1. AV node 2. SA node 3. atria 4. Purkinje fibers 5. bundle of His 6. ventricular myocardium a. 231546 b. 321456 c. 231456 d. 123456 e. none of these

ANS: A PTS: 1 DIF: Comprehension

3. Which one of the following involves a response of a skeletal muscle through an efferent output? a. augmented breathing from the diaphragm b. delayed emptying of the stomach c. increased pumping of blood d. increased secretion of insulin e. initiation of sweating

ANS: A PTS: 1 DIF: Comprehension

3. Resistance increases when a. vessel radius decreases b. vessel length decreases c. blood viscosity decreases d. red blood cell count decreases e. both a and b occurs

ANS: A PTS: 1 DIF: Comprehension

30. An EPP a. occurs because of Na+ diffusing into a muscle fiber after ACh binds with a receptor on the muscle fiber b. is usually smaller in magnitude than an EPSP c. is terminated when Ca2+ inactivates acetylcholine d. has characteristics a and b e. has characteristics a and c

ANS: A PTS: 1 DIF: Comprehension

30. The SA node is the heart's normal pacemaker because a. it has the fastest rate of autorhythmicity b. it has both sympathetic and parasympathetic innervation c. it lies in the right atrium d. activation of K+ channels occurs more rapidly in this region than elsewhere in the heart e. it can directly stimulate atrial and ventricular cardiac myocardial contractile cells

ANS: A PTS: 1 DIF: Comprehension

35. The function of the ventricular conduction system of the heart is to a. spread the action potential throughout the ventricle to ensure a single, coordinated contraction of the both ventricles b. spread the action potential in the absence of sympathetic stimulation c. spread the action potential throughout the atria and ventricles d. slow down the original action potential so it has time to spread through the ventricles evenly e. perform both a and d

ANS: A PTS: 1 DIF: Comprehension

39. During a cross-bridge cycle in skeletal muscle, a. the cross bridge is energized when it splits ATP into ADP and P b. the cross bridge must bind with ATPase before a power stroke will occur c. Ca2+ causes tropomyosin to move off of the myosin's actin-binding sites d. ADP binds to the cross bridge at the end of the power stroke e. both a and b occur

ANS: A PTS: 1 DIF: Comprehension

41. The cardiac output is equal to a. (EDV - ESV) x HR b. heart rate x EDV c. the difference between the stroke volume at rest and the stroke volume during exercise d. the stroke volume minus the ESV e. heart rate x blood pressure

ANS: A PTS: 1 DIF: Comprehension

48. As the total cross-sectional area of the vascular tree ____, the velocity of blood flow ____. a. increases; decreases b. increases; increases c. decreases; decreases d. increases; remains constant e. decreases; remains constant

ANS: A PTS: 1 DIF: Comprehension

5. What system would suppress the digestive organs during times of greater physical activity? a. sympathetic b. parasympathetic c. enteric nervous system d. somatic nervous system e. none of these

ANS: A PTS: 1 DIF: Comprehension

50. To pick up something heavier than your pencil, your nervous system could a. stimulate larger motor units b. decrease the frequency of stimulation to allow a more prolonged contraction to occur c. decrease the refractory periods d. block acetylcholinesterase at the neuromuscular junction to allow acetylcholine to function longer e. do all of the above

ANS: A PTS: 1 DIF: Comprehension

50. When the heart is sympathetically stimulated, a. ESV will likely decrease b. it is responding to acetylcholine c. the fibrous skeleton of the heart is depolarizing d. its stroke volume will decrease e. all except c will occur

ANS: A PTS: 1 DIF: Comprehension

53. Fluid movement into and out of the capillary is dependent on the blood's ____ and ____ working in ____ direction(s). a. hydrostatic pressure, osmotic pressure, opposite b. hydrostatic pressure, osmotic pressure, the same c. ultrafiltration rate, bulk flow rate, the same d. ultrafiltration rate, bulk flow rate, opposite e. protein removal rate, hydrostatic pressure, the same

ANS: A PTS: 1 DIF: Comprehension

53. Muscle tension a. is created when tension generated by sarcomeres is transmitted via the connective tissue and tendons to the bones b. is the force exerted on a muscle by the weight of an object c. is greater than the load during an isometric contraction d. is all of the above e. is none of the above

ANS: A PTS: 1 DIF: Comprehension

53. The aortic valve opens a. when ventricular pressure exceeds aortic pressure b. just before ventricular systole begins c. just after the isovolumetric relaxation phase d. in response to the repolarization of contractile cells in the left ventricle e. just before atrial diastole begins

ANS: A PTS: 1 DIF: Comprehension

55. What is the primary method by which materials such as O2, CO2, and nutrients are exchanged between the blood and surrounding tissues? a. passive diffusion across the capillary wall down their concentration gradients b. active transport across the capillary wall c. osmotic pressure drawing water and solutes out of the capillary and bringing these dissolved nutrients into contact with the tissue cells d. ultrafiltration and reabsorption e. bulk flow

ANS: A PTS: 1 DIF: Comprehension

6. Actin a. does not perform a power stroke during muscle contraction b. contains a globular head that forms a cross bridge between the thick and thin filaments c. is not found within A bands d. is inhibited by Ca2+ e. does not attach to the Z lines

ANS: A PTS: 1 DIF: Comprehension

61. Edema could result from a. blockage of lymph vessels b. increased capillary blood pressure c. decreased blood osmotic pressure d. all of the above e. only a and b

ANS: A PTS: 1 DIF: Comprehension

70. Sympathetic stimulation of veins ____ venous pressure and drives ____ blood into the heart. a. increases; more b. increases; less c. decreases; more d. decreases; less e. None of choices above correctly complete the sentence.

ANS: A PTS: 1 DIF: Comprehension

75. In the body's lever systems, the fulcrums are represented by the a. joints b. long bones c. tendons d. short bones e. skeletal muscles

ANS: A PTS: 1 DIF: Comprehension

99. Pacemaker activity refers to spontaneous depolarizations resulting from a. shifts in passive ionic fluxes accompanying b. cyclical changes in Na+-K+ pump activity c. automatic changes in channel permeability d. both a and b e. both a and c

ANS: A PTS: 1 DIF: Comprehension

11. Select the incorrect statement about the parasympathetic nervous system. a. It inhibits all cardiac muscle and smooth muscle. b. Neurotransmitter from all its postganglionic fibers bind to muscarinic receptors. c. Neurotransmitter from all its preganglionic fibers bind to nicotinic receptors. d. Part of it originates in the brain e. Part of it originates in the most inferior region of the spinal cord.

ANS: A PTS: 1 DIF: Knowledge

12. Which statement is correct about terminal ganglia? a. Those on parasympathetic preganglionic fibers lie in or near the effector organ. b. They give rise to sympathetic postganglionic fibers. c. They are the final common pathway for the autonomic nervous system. d. They contain muscarinic receptors. e. They lie in a chain located along either side of the spinal cord.

ANS: A PTS: 1 DIF: Knowledge

15. Skeletal muscle fibers a. are some of the longest cells in the body b. are attached end-to-end within a muscle c. contain Z lines within their A bands d. contain only one nucleus e. exhibit characteristics b and c

ANS: A PTS: 1 DIF: Knowledge

18. Atropine ____ the effect of acetylcholine at ____ receptors and ____ ____ receptors. a. blocks; muscarinic; does not affect; nicotinic b. enhances; muscarinic; does not affect; nicotinic c. blocks; nicotinic; does not affect; muscarinic d. enhances; nicotinic; does not affect; muscarinic e. blocks; muscarinic; enhances; nicotinic

ANS: A PTS: 1 DIF: Knowledge

18. Troponin a. binds with calcium to allow sarcomere shortening b. breaks down myosin cross bridges c. is an enzyme in the sarcomere d. forms the boundaries of a sarcomere e. has an ATPase site

ANS: A PTS: 1 DIF: Knowledge

20. The AV nodal delay ensures that: a. The atria contract and empty their contents into the ventricles prior to ventricular systole. b. The ventricles contract prior to atrial systole. c. Tetanic contractions of cardiac muscle are impossible. d. Ventricular diastole occurs before systole. e. Atrial diastole occurs before atrial systole.

ANS: A PTS: 1 DIF: Knowledge

21. The normal pacemaker of the heart is the a. SA node b. AV node c. bundle of His d. Purkinje system e. ventricular myocardium

ANS: A PTS: 1 DIF: Knowledge

21. The pulse pressure is the a. difference between the systolic and diastolic pressures b. average pressure throughout the cardiac cycle c. maximum pressure exerted in the arteries d. minimum pressure exerted in the arteries e. change in pressure that can be felt in an artery due to shutting of the aortic valve

ANS: A PTS: 1 DIF: Knowledge

27. Which of the following properties does not pertain to the arterioles? a. Their radii remain constant. b. Their walls contain a relatively thick layer of smooth muscle. c. They are responsible for the distribution of blood flow to the various organs. d. They are the major vessels that contribute to total peripheral resistance. e. They are richly innervated by sympathetic nerve fibers.

ANS: A PTS: 1 DIF: Knowledge

3. Myosin a. is found in the A band b. is found in the I band c. is in the thin filaments d. shortens during muscle contraction because it is one of the contractile proteins e. is found in the Z line

ANS: A PTS: 1 DIF: Knowledge

30. Which local chemical factor is not associated with vasodilation of arterioles? a. decreased nitric oxide b. increased CO2 c. increased acid d. decreased O2 e. increased histamine

ANS: A PTS: 1 DIF: Knowledge

32. Which statement about nitric oxide is incorrect? a. It increases the total peripheral resistance by its action on arteriolar smooth muscle. b. It relaxes digestive tract smooth muscle. c. It is the direct mediator of penile erection. d. It is released as "chemical warfare" by macrophages of the immune system. e. It serves as a novel type of neurotransmitter in the brain.

ANS: A PTS: 1 DIF: Knowledge

33. Botulism is caused by a toxin from bacteria in the species a. Clostridium b. Escherichia c. Salmonella d. Staphylococcus e. Streptococcus

ANS: A PTS: 1 DIF: Knowledge

34. An ectopic focus is the place where a. an abnormally excitable area of the heart initiates a premature action potential b. all of the electrical impulses of the heart terminate normally c. an ECG lead is attached on the outside of the chest d. a heart valve is attached e. the chordae tendineae attach to a valve

ANS: A PTS: 1 DIF: Knowledge

34. The sarcoplasmic reticulum stores ____ when a muscle is relaxed and releases it for binding to ____ during contraction. a. calcium; troponin b. calcium; tropomyosin c. sodium; tropomyosin d. potassium; tropomyosin e. sodium; troponin

ANS: A PTS: 1 DIF: Knowledge

35. Curare a. strongly binds to acetylcholine receptor sites b. inhibits acetylcholinesterase c. is found in pesticides and military nerve gases d. has characteristics a and b e. has characteristics b and c

ANS: A PTS: 1 DIF: Knowledge

36. The major site of sympathetic blood flow control (resistance changes) is at the a. arterioles b. capillaries c. metarterioles d. arteries e. veins

ANS: A PTS: 1 DIF: Knowledge

36. Which statement is not true about cross bridges? a. They are a component of thin filaments. b. They are comprised of myosin. c. They have an actin binding site. d. They have an ATPase binding site. e. They provide power stroking.

ANS: A PTS: 1 DIF: Knowledge

43. Active hyperemia refers to a. arteriolar dilation in response to local chemical changes that accompany increased metabolic activity of the tissue b. local arteriolar mechanisms that are aimed at keeping tissue blood flow fairly constant in spite of wide deviations in mean arterial driving pressure c. the increase in blood flow to a tissue that occurs after removal of an occlusion of its blood supply d. maintaining adequate mean arterial pressure to drive blood forward into a tissue e. none of the above

ANS: A PTS: 1 DIF: Knowledge

45. Which of the following selectively activates beta-2 receptors at low doses, making it possible to dilate bronchioles in the treatment of asthma? a. salbuterol b. atropine c. metoprolol d. neostigmine e. curare

ANS: A PTS: 1 DIF: Knowledge

46. A motor unit refers to a. a single motor neuron plus all of the muscle fibers it innervates b. a single muscle fiber plus all of the motor neurons that innervate it c. all of the motor neurons supplying a single muscle d. a pair of antagonistic muscles e. a sheet of smooth muscle cells connected by gap junctions

ANS: A PTS: 1 DIF: Knowledge

49. In most tissues, glucose, a water-soluble substance, crosses capillary walls through a. water-filled pores b. endothelial cells c. sinusoids d. a and b e. a and c

ANS: A PTS: 1 DIF: Knowledge

49. Twitch summation a. results from increases in cytosolic calcium levels b. results from pumping of calcium into the sarcoplasmic reticulum c. can be enhanced by allowing a cell to completely relax d. rarely results in tetany e. is not characterized by any of the above

ANS: A PTS: 1 DIF: Knowledge

5. Adjacent cardiac muscle cells are joined together end-to-end in the ventricles by a. intercalated discs b. sarcomeres c. Purkinje fibers d. sinoatrial nodes e. atrioventricular nodes

ANS: A PTS: 1 DIF: Knowledge

55. The period lasting from closure of the AV valve to opening of the aortic valve is known as a. isovolumetric ventricular contraction b. isovolumetric ventricular relaxation c. the rapid ejection phase d. the rapid filling phase e. ventricular diastole

ANS: A PTS: 1 DIF: Knowledge

58. The dicrotic notch on the aortic pressure curve is due to a. a disturbance set up by the aortic valve closing b. a disturbance set up when the AV valves close c. elastic recoil of the aorta during ventricular diastole d. turbulent flow through a stenotic valve e. atherosclerosis in the aorta

ANS: A PTS: 1 DIF: Knowledge

61. A whistling murmur heard between the second and first heart sound would be indicative of a. a stenotic AV valve b. an insufficient AV valve c. a myocardial infarction d. an insufficient semilunar valve e. an everted AV valve during atrial diastole

ANS: A PTS: 1 DIF: Knowledge

63. The first means by which ATP is produced at the onset of contractile activity is a. transfer of energy and phosphate from creatine phosphate to ADP b. oxidative phosphorylation c. glycolysis d. degradation of myoglobin e. none of these

ANS: A PTS: 1 DIF: Knowledge

7. The chordae tendineae a. keep the AV valves from averting during ventricular systole b. hold the AV valves open during diastole c. hold the right and left ventricles together d. transmit the electrical impulse from the atria to the ventricles e. contract when the ventricles contract

ANS: A PTS: 1 DIF: Knowledge

79. The corticospinal system a. consists of fibers originating in the primary motor cortex and terminating on motor neurons b. involves the motor regions of the cortex, cerebellum, basal nuclei, and thalamus c. is primarily concerned with regulation of body posture d. has characteristics a and b e. has characteristics b and c

ANS: A PTS: 1 DIF: Knowledge

85. Stretch reflexes are important for a. maintaining balance and posture b. providing afferent information to the primary motor cortex c. determining which skeletal muscles will be used for a certain activity. d. both a and b e. both b and c

ANS: A PTS: 1 DIF: Knowledge

89. The regulation of smooth muscle contraction is mediated by the phosphorylation of ____ in response to calcium binding to ____. a. myosin; calmodulin b. actin; calmodulin c. troponin; calmodulin d. myosin; troponin e. actin; troponin

ANS: A PTS: 1 DIF: Knowledge

92. Calcium that enters the cell during smooth muscle excitation binds with a. calmodulin b. inactive myosin kinase c. troponin d. myosin e. actin

ANS: A PTS: 1 DIF: Knowledge

63. Twelve complete ECG patterns are recorded over 10 seconds, which means the heart rate is ____ beats per minute. a. 60 b. 72 c. 90 d. 108 e. 120

ANS: B PTS: 1 DIF: Analysis

74. Mean arterial blood pressure a. equals stroke volume times heart rate b. is 91 mm Hg when the blood pressure is recorded as 117/78 c. is 97.5 mm Hg when the blood pressure is recorded as 117/78 d. is both a and b e. is both a and c

ANS: B PTS: 1 DIF: Analysis

78. Which of the following is not associated with sympathetic stimulation? a. Constriction of arterioles, which increases peripheral resistance b. Decreased end diastolic volume, which increases cardiac output c. Increased stroke volume, which increases cardiac output d. Constriction of veins, which increases venous return e. Constriction of veins, which increases stroke volume

ANS: B PTS: 1 DIF: Analysis

83. A sudden increase in pressure within the carotid sinus leads to a. increased sympathetic nerve activity b. increased parasympathetic nerve activity c. increased cardiac output d. increased peripheral resistance e. none of the above

ANS: B PTS: 1 DIF: Analysis

1. The systemic circulation a. receives more blood than the pulmonary circulation does b. receives blood from the left ventricle c. is a low pressure system compared to the pulmonary circulation d. has characteristics a and b e. has characteristics b and c

ANS: B PTS: 1 DIF: Comprehension

21. According to the sliding-filament mechanism, the a. A bands slide between the I bands b. thin filaments slide inward toward the center of the A band c. Z lines slide between the T tubules d. contractile proteins shorten, thus shortening the sarcomere e. filaments slide past the lateral sacs of the sarcoplasmic reticulum

ANS: B PTS: 1 DIF: Comprehension

22. During contraction of skeletal muscle fibers, the a. contractile proteins shorten b. thin filaments slide inward toward the A band's center as a result of cycles of cross-bridge binding and bending c. thick and thin filaments become tightly coiled, thus shortening the sarcomere d. I bands slide in between the A bands e. lateral sacs of the sarcoplasmic reticulum shorten, pulling the Z lines closer together

ANS: B PTS: 1 DIF: Comprehension

26. Depolarization occurs at the AV node a. during the P wave b. between the P wave and QRS complex c. during the QRS complex d. between the QRS complex and T wave e. during the T wave

ANS: B PTS: 1 DIF: Comprehension

26. Which of the following changes in banding pattern occur during muscle relaxation? a. Thin filaments move away from the Z lines. b. I bands get wider. c. H zones get narrower. d. Thick filaments become longer. e. Both b and c occur.

ANS: B PTS: 1 DIF: Comprehension

33. Binding of ____ to myosin permits the cross-bridge to ____. a. ATP; bind with actin b. ATP; detach from actin c. calcium; bind with actin d. calcium; detach from actin e. None of the above correctly complete the sentence.

ANS: B PTS: 1 DIF: Comprehension

33. The electrocardiogram is most useful in determining which component of cardiac output? a. stroke volume b. heart rate c. ejection fraction d. end-diastolic volume e. murmurs

ANS: B PTS: 1 DIF: Comprehension

35. Of the steps in excitation-contraction below, which step occurs before the others? a. Exposed actin sites bind with myosin cross bridges. b. Sodium channels open in the fiber's membrane. c. Calcium is released from the sarcoplasmic reticulum. d. Troponin binds calcium. e. Attachment of ATP allows for cross bridge detachment.

ANS: B PTS: 1 DIF: Comprehension

39. During isovolumetric phases of the cardiac cycle, a. the atria are contracting b. all heart valves are closed c. blood is being ejected into the aorta d. the ventricles can only be relaxing e. both a and b are true

ANS: B PTS: 1 DIF: Comprehension

4. Which is not characteristic of sympathetic pathways? a. Fibers originate from the thoracic and lumbar levels b. Preganglionic fibers release norepinephrine c. Some postganglionic fibers release ACh d. Short preganglionic fibers e. Most preganglionic fibers synapse in the chain ganglia

ANS: B PTS: 1 DIF: Comprehension

43. If the connection between the SA node and AV node becomes blocked, a. the QRS complex will be absent on an ECG b. the ventricles will beat more slowly c. the atria will beat slower d. tachycardia will occur e. both a and d will occur

ANS: B PTS: 1 DIF: Comprehension

45. Which of the following leads to a decrease in ESV? a. acetylcholine b. preload c. afterload d. parasympathetic activity e. vagal activity

ANS: B PTS: 1 DIF: Comprehension

54. During isovolumetric 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. the maximum rate of ejection occurs e. Both a and b occur

ANS: B PTS: 1 DIF: Comprehension

60. In a muscle fiber undergoing maximal tetanic stimulation, the velocity of shortening ____ as the load ____. a. decreases; decreases b. decreases; increases c. increases; increases d. remains constant; increases e. remains constant; decreases

ANS: B PTS: 1 DIF: Comprehension

62. Each of the following factors promotes the function of the capillaries except a. a blood pressure forcing fluid out of these vessels b. a small total surface area c. an osmotic pressure drawing fluid into these vessels d. pores in the endothelial wall e. thin walls

ANS: B PTS: 1 DIF: Comprehension

66. According to the Frank-Starling law of the heart, a. shortening cardiac muscle fibers prior to contraction causes more forceful contractions b. increasing venous return increases EDV, which leads to an increased stroke volume c. as cardiac output decreases, blood pools in the vasculature and increases arterial blood pressure d. the left ventricle must pump more blood than the right ventricle since the left ventricle must pump blood to more regions of the body e. the greater the stroke volume, the smaller the subsequent ESV, because as more blood is squeezed out, the heart cannot fill as completely.

ANS: B PTS: 1 DIF: Comprehension

67. Which of the following statements about the different types of muscle fibers is incorrect? a. The higher the ATPase activity, the faster the speed of contraction. b. Muscles with a high glycolytic capacity and large glycogen stores are more resistant to fatigue. c. Muscles with high ATP-synthesizing ability are more resistant to fatigue. d. Oxidative types of muscle fibers contain myoglobin. e. Muscle fibers containing large amounts of myoglobin have a dark red color in comparison to the paler fibers, which have little myoglobin.

ANS: B PTS: 1 DIF: Comprehension

7. Vasoconstriction a. causes a decrease in resistance b. refers to a decrease in the radius of a vessel c. is due to a decrease in sympathetic activity d. is both a and b e. is both b and c

ANS: B PTS: 1 DIF: Comprehension

70. The muscle cells of a marathon runner's legs would exhibit all these characteristics except a. high resistance to fatigue b. low myoglobin content c. low glycogen content d. many mitochondria e. slow speed of contraction

ANS: B PTS: 1 DIF: Comprehension

74. If the EDV were held constant, increased cardiac output could be accomplished by a. decreased sympathetic stimulation of the heart b. decreased parasympathetic stimulation of the heart c. decreased contractility d. increased length of isovolumetric contraction e. increased arterial blood pressure

ANS: B PTS: 1 DIF: Comprehension

77. All the following compensate for a fall in blood pressure below normal except a. increased cardiac output b. decreased total peripheral resistance c. increased heart rate d. venous vasoconstriction e. increased stroke volume

ANS: B PTS: 1 DIF: Comprehension

8. The heart chamber that has the greatest work load is a. the right ventricle b. the left ventricle c. the left atrium d. the right atrium e. both atria

ANS: B PTS: 1 DIF: Comprehension

96. A functional syncytium a. is a pair of antagonistic muscles causing a joint to move in opposite directions b. is able to contract as a unit because action potentials move between adjacent cells through gap junctions c. is a functional junction between a smooth muscle fiber and an autonomic nerve ending d. is all of the above e. is none of the above

ANS: B PTS: 1 DIF: Comprehension

98. Repaying the oxygen deficit after strenuous exercise involves a. formation of lactate in the muscle cells b. replenishing stores of creatine phosphate and glycogen c. unloading oxygen from myoglobin d. all of the above e. both b and c

ANS: B PTS: 1 DIF: Comprehension

1. At rest, which of the following receives the most blood flow? a. heart muscle b. kidney c. brain d. skeletal muscle e. bone

ANS: B PTS: 1 DIF: Knowledge

1. The autonomic nervous system is a. part of the somatic nervous system b. the involuntary branch of the peripheral nervous system's efferent division c. part of the central nervous system d. part of the afferent division of the nervous system e. all of these

ANS: B PTS: 1 DIF: Knowledge

10. The aortic valve a. prevents the backflow of blood into the aorta during ventricular diastole b. prevents the backflow of blood into the left ventricle during ventricular diastole c. prevents the backflow of blood into the right ventricle during ventricular diastole d. closes when the first heart sound is heard e. does not do any of the above

ANS: B PTS: 1 DIF: Knowledge

10. Which of the following does not characterize the sympathetic nervous system? a. It promotes responses that prepare the body for strenuous physical activity. b. It has some afferent fibers. c. Most of its postganglionic fibers are adrenergic. d. Its effects may be excitatory or inhibitory. e. Its postganglionic neurons display nicotinic receptors.

ANS: B PTS: 1 DIF: Knowledge

10. Z lines a. are formed by the T tubules b. extend down the middle of the I band c. are formed by cross bridges d. are part of the thin filaments e. extend down the middle of the sarcomere

ANS: B PTS: 1 DIF: Knowledge

12. Blood returning from the lungs a. enters the right atrium b. enters the left atrium c. is poorly oxygenated d. passes through the pulmonary valve before entering the heart e. pass through the aortic valve before entering the heart

ANS: B PTS: 1 DIF: Knowledge

13. Skeletal muscle fibers a. have T tubules within their sarcomeres b. have Z lines extending down the middle of the I bands c. contain gap junctions d. have all of the above characteristics e. have characteristics b and c

ANS: B PTS: 1 DIF: Knowledge

14. The microcirculation is composed of a. arteries, arterioles, and capillaries b. arterioles, capillaries, and venules c. arteries, capillaries, and venules d. arteries, arterioles, and venules e. capillaries only

ANS: B PTS: 1 DIF: Knowledge

17. Nicotinic receptors a. bind with acetylcholine released from parasympathetic postganglionic fibers b. respond to acetylcholine released from sympathetic and parasympathetic preganglionic fibers c. are found primarily in the heart d. bind with norepinephrine released from sympathetic postganglionic fibers e. are found on certain effectors of the parasympathetic nervous system

ANS: B PTS: 1 DIF: Knowledge

19. The pressure measured in the arteries just before the next ventricular ejection of blood is a. systolic pressure b. diastolic pressure c. pulse pressure d. mean venous pressure e. mean arterial pressure

ANS: B PTS: 1 DIF: Knowledge

21. Acetylcholinesterase a. has enhanced activity from organophosphates b. inactivates a neurotransmitter. c. is a neurotransmitter d. stimulates an EPSP e. triggers the release of sodium from postsynaptic cells

ANS: B PTS: 1 DIF: Knowledge

25. What force continues to drive blood through the vasculature during ventricular diastole? a. contraction of the ventricles b. elastic recoil of the stretched arteries c. sympathetic-induced vasoconstriction d. skeletal muscles squeezing the blood e. respiratory movements creating a pressure gradient that drives blood forward

ANS: B PTS: 1 DIF: Knowledge

28. What is the fate of ACh following binding to receptors? a. It remains bound, causing continued excitement. b. It is removed by acetylcholinesterase. c. It is actively reabsorbed by the axon terminal. d. It is passively reabsorbed by the muscle cell. e. None of the above.

ANS: B PTS: 1 DIF: Knowledge

29. The T tubules a. store Ca2+ b. provide a means of rapidly transmitting the action potential from the surface into the central portions of the muscle fiber c. store ATP d. run longitudinally between the myofibrils e. have expanded lateral sacs

ANS: B PTS: 1 DIF: Knowledge

31. Efferent neurons a. have cell bodies located only within ganglia b. are part of a two-neuron chain in the autonomic nervous system c. arise peripherally at a receptor d. send information toward the CNS e. signal only skeletal muscles

ANS: B PTS: 1 DIF: Knowledge

31. Which of the following does not cause relaxation of smooth muscle within local arterioles? a. carbon dioxide b. endothelin c. nitric oxide d. histamine e. increased osmolarity

ANS: B PTS: 1 DIF: Knowledge

32. The AV node a. is the normal pacemaker of the heart b. is the only electrical connection between the atria and the ventricles c. rapidly conducts impulses from the atria to the ventricles so that they contract simultaneously d. is not innervated by the vagus nerve e. has the slowest rate of depolarization in the heart

ANS: B PTS: 1 DIF: Knowledge

34. Which of the following chemicals paralyzes skeletal muscle by binding to the acetylcholine receptor sites? a. black widow spider venom b. curare c. organophosphates d. insecticide e. local anesthetics

ANS: B PTS: 1 DIF: Knowledge

37. The membrane potential of cardiac contractile cells at rest is about ____ mV. a. -110 b. -90 c. -70 d. -50 e. -30

ANS: B PTS: 1 DIF: Knowledge

39. Which of the following is least related to the innervation of skeletal muscle cells? a. acetylcholine b. varicosities c. neuromuscular junction d. somatic nervous system e. motor neuron

ANS: B PTS: 1 DIF: Knowledge

42. Binding of epinephrine to alpha receptors causes smooth muscle a. relaxation in arteries of the brain b. relaxation in skeletal muscle arteries c. constriction in skeletal muscle arteries d. relaxation in coronary arteries e. to not experience any of the above

ANS: B PTS: 1 DIF: Knowledge

43. Binding of neurotransmitter to which of the following receptors on an effector would likely cause inhibition of the effector? a. alpha-1 b. alpha-2 c. beta-1 d. Both a and b e. Both a and c

ANS: B PTS: 1 DIF: Knowledge

56. A heart valve opens and closes due to a. being pulled by the heart muscle b. pressure differences on the valve's two sides c. Na+ and K+ fluxes during ventricular depolarization d. turbulent flow in the atria and ventricles e. none of the above

ANS: B PTS: 1 DIF: Knowledge

57. Cardiac output a. is the volume of blood pumped by each ventricle during each contraction or beat b. is the volume of blood pumped by each ventricle per minute c. equals heart rate divided by stroke volume d. is both a and c e. is both b and c

ANS: B PTS: 1 DIF: Knowledge

57. With eccentric muscle contractions, a. development of tension occurs at constant muscle length b. muscles lengthen while contracting c. muscles shorten while contracting d. muscle length and tension vary throughout a range of motion e. none of the above occur

ANS: B PTS: 1 DIF: Knowledge

59. Muscles developing tension while lengthening are performing ____ contractions. a. concentric b. eccentric c. isometric d. fatiguing e. oscillating

ANS: B PTS: 1 DIF: Knowledge

6. Postganglionic autonomic fibers a. end in a single synaptic knob that releases the neurotransmitter b. have numerous varicosities that simultaneously release neurotransmitter over a large area of the innervated organ rather than on single cells c. innervate skeletal, smooth, and cardiac muscle d. have characteristics a and c e. have characteristics b and c

ANS: B PTS: 1 DIF: Knowledge

6. The primary function of the pericardial sac is to a. prevent excessive expansion of the heart as it fills with blood b. secrete a fluid that reduces friction as the heart beats c. serve as a reservoir for blood to be used during strenuous exercise d. provide oxygen and nutrients to the heart muscle e. catch and kill any bacteria in the blood flowing through the heart chambers

ANS: B PTS: 1 DIF: Knowledge

60. Atrial flutter is characterized by a ____ rhythm, as impulses pass from the AV node to the ventricles. a. 1:1 b. 2:1 c. 3:4 d. 5:2 e. 7:1

ANS: B PTS: 1 DIF: Knowledge

60. What is the primary reason that edema may occur with serious burns? a. increased venous pressure due to interference with circulation through scarring in the burned area b. lowering of blood osmotic pressure due to the loss of protein-rich fluid from the surface of the burn c. blockage of lymphatic drainage from the burned area d. loss of protein in the urine e. increased tissue hydrostatic pressure

ANS: B PTS: 1 DIF: Knowledge

62. At rapid heart rates a. systole and diastole shorten equally b. systole stays almost constant, but diastole shortens c. systole lengthens and diastole shortens d. diastole lengthens and systole shortens e. none of the above occur

ANS: B PTS: 1 DIF: Knowledge

68. The venous valves a. actively contract to force blood uphill against gravity b. passively close to prevent the backflow of blood in the veins c. prevent blood from flowing into lymphatic vessels d. primarily prevent blood plasma from moving into the interstitial fluid e. perform all of the above functions

ANS: B PTS: 1 DIF: Knowledge

69. Fast-oxidative (type IIa) fibers a. contain very few mitochondria b. can be converted into fast-glycolytic fibers by regular resistance activities c. are most abundant in muscles specialized for maintaining low-intensity contractions for long periods of time without fatigue d. have characteristics b and c e. have none of the above characteristics

ANS: B PTS: 1 DIF: Knowledge

69. Heart and venous valves serve a similar function. They prevent a ____ flow of blood. a. forward b. backward c. turbulent d. pulsatile e. laminar

ANS: B PTS: 1 DIF: Knowledge

73. Which of the following does not directly influence motor neurons? a. primary motor cortex b. cerebellum c. brain stem d. afferent neurons (through intervening interneurons) e. None of the above

ANS: B PTS: 1 DIF: Knowledge

74. When a muscle atrophies, its muscle fibers a. split lengthwise b. decreases in mass and becomes weaker c. increase in diameter d. undergo mitotic cell division e. dissolve and are replaced by fibrous scar tissue

ANS: B PTS: 1 DIF: Knowledge

79. A swishy murmur heard between the second and first heart sounds is indicative of a(n) ____________ valve. a. insufficient semilunar b. insufficient AV c. stenotic semilunar d. stenotic AV e. Either a or d correctly completes the sentence.

ANS: B PTS: 1 DIF: Knowledge

8. Sarcomeres are arranged end to end as a. Z lines b. myofibrils c. T tubules d. myofilaments e. cross bridges

ANS: B PTS: 1 DIF: Knowledge

8. The major determinant influencing resistance to blood flow is the a. viscosity of the blood b. radius of the vessel through which the blood is flowing c. pressure gradient in the vessel d. concentration of red blood cells in the blood e. amount of plasma protein

ANS: B PTS: 1 DIF: Knowledge

81. Spastic paralysis occurs when a. descending excitatory pathways are destroyed b. excitatory inputs to motor neurons are unopposed because of disruption of an inhibitory system in the brain stem c. muscle spindles are destroyed d. the cerebellum is damaged e. the motor neurons are destroyed

ANS: B PTS: 1 DIF: Knowledge

81. The cardiovascular center responds to rising H+/CO2 by a. dilating arteries b. constricting arterioles c. increasing respiratory rate d. slowing the heart rate e. decreasing venous return

ANS: B PTS: 1 DIF: Knowledge

82. During coactivation, a. all muscle fibers in a skeletal muscle are activated simultaneously b. the gamma motor-neuron and alpha motor-neuron systems to a skeletal muscle are activated simultaneously c. all cross bridges within a single skeletal muscle are activated simultaneously d. the primary (annulospiral) and secondary (flower-spray) endings within a muscle spindle are activated simultaneously e. none of the above occur

ANS: B PTS: 1 DIF: Knowledge

9. In an arteriole, if the blood vessel radius is 2 units and is then vasoconstricted to 1 unit, a. blood flow decreases by half b. resistance increases 16 times c. blood viscosity increases d. all of the above will occur e. only b and c occur

ANS: B PTS: 1 DIF: Knowledge

56. Given the following parameters, what would the reabsorption pressure be? - Blood pressure at arteriolar end of capillary = 35 mm Hg - Blood pressure at venule end of capillary = 15 mm Hg - Blood osmotic pressure = 22 mm Hg - Interstitial fluid hydrostatic pressure = 1 mm Hg - Interstitial fluid osmotic pressure: 0 mm Hg a. 6 mm Hg b. 7 mm Hg c. 8 mm Hg d. 10 mm Hg e. 22 mm Hg

ANS: C PTS: 1 DIF: Analysis

64. If stroke volume is 80 ml and the heart rate is 70 beats per minute, the cardiac output is a. 150 ml/min b. 560 ml/min c. 5,600 ml/min d. 8,700 ml/min e. none of the above

ANS: C PTS: 1 DIF: Analysis

65. If the cardiac output is 4,800 ml/min and the heart rate is 60 beats per minute, the stroke volume averages ____ ml. a. 60 b. 70 c. 80 d. 120 e. 140

ANS: C PTS: 1 DIF: Analysis

104. Which of the following is most closely associated with a skeletal muscle fiber's latent period? a. hyperpolarization b. relaxation c. diffusion of calcium out of the SR's lateral sacs d. development of tension e. shortening of the muscle fiber

ANS: C PTS: 1 DIF: Comprehension

15. Parasympathetic stimulation ____ heart rate and ____ the motility in the digestive tract. a. does not affect; increases b. decreases; decreases c. decreases; increases d. increases; decreases e. increases; increases

ANS: C PTS: 1 DIF: Comprehension

16. The plateau of the cardiac action potential results from the opening of voltage-gated slow ____ channels in the plasma membrane of the ____ cell. a. sodium; contractile b. potassium; autorhythmic c. calcium; contractile d. chloride; pacemaker e. potassium; contractile

ANS: C PTS: 1 DIF: Comprehension

19. During contraction of a sarcomere, a. the Z discs move farther apart b. the A bands become thicker c. the I bands become narrower d. the thin filaments become shorter e. events c and d occur

ANS: C PTS: 1 DIF: Comprehension

20. A function of tropomyosin is a. to bind Ca2+ b. to form attachments with myosin cross bridges c. to prevent myosin cross bridges from attaching to the thin filaments d. to act as an ATPase e. none of the above

ANS: C PTS: 1 DIF: Comprehension

20. The sympathetic nervous system causes a. blood vessels with alpha receptors to dilate b. bronchioles to constrict c. pupils of the eye to dilate d. sweat glands to be inhibited e. the urinary bladder to contract and eliminate urine

ANS: C PTS: 1 DIF: Comprehension

22. The function of the atrioventricular node is to a. excite the left and right atrium b. control the heart rate c. prevent the atria and ventricles from contracting simultaneously d. repolarize the heart after systole e. stimulate ventricular contractile cells directly

ANS: C PTS: 1 DIF: Comprehension

24. During muscle contraction, a. the Z lines move farther away from the thick filaments b. the A band becomes narrower c. the H zone becomes narrower or disappears d. the I band remains unchanged e. both b and c occur

ANS: C PTS: 1 DIF: Comprehension

26. Acetylcholine a. binds to cholinergic receptors on preganglionic neurons and skeletal muscle cells b. destroys acetylcholinesterase c. binds to muscarinic receptors d. is released from all postganglionic neurons e. does all of the above except b

ANS: C PTS: 1 DIF: Comprehension

27. During contraction, asynchronous cycling of cross bridges a. prevents tetany b. prevents thick filaments from slipping backwards c. prevents thin filaments from slipping backwards d. utilizes less ATP e. does not do any of the above

ANS: C PTS: 1 DIF: Comprehension

30. Sequence the following events involved in muscle cell contraction: 1. Sodium channels open and sodium flows in. 2. Impulse reaches the axon's terminal. 3. ACh binds to receptors on the muscle cell membrane. 4. Synaptic vesicles fuse with neuron's membrane and release ACh via exocytosis. 5. If enough sodium moves in to the muscle cell, an impulse (action potential) develops. a. 1, 2, 3, 4, 5 b. 2, 1, 3, 4, 5 c. 2, 4, 3, 1, 5 d. 3, 4, 5, 1, 2 e. 3, 5, 2, 1, 4

ANS: C PTS: 1 DIF: Comprehension

38. Why can't tetanus occur in the heart? a. There are no distinct motor units in the heart. b. There is inadequate oxygen supply via the coronary circulation to metabolically support a sustained contraction. c. The refractory period in cardiac muscle lasts almost as long as the contraction. d. The heart contracts with maximal force every beat so it is impossible to increase the strength of its contraction. e. Vagal stimulation slows down the heart rate to prevent summation of contractions.

ANS: C PTS: 1 DIF: Comprehension

4. The wall of the left ventricle is thicker than the wall of the right ventricle, which allows the a. left ventricle to pump much more blood than the right ventricle b. right ventricle to hold more blood than the left ventricle c. left ventricle to pump blood into a higher-resistance, higher-pressure system d. right ventricle to create higher tension within its walls e. left ventricle to pump oxygenated blood,

ANS: C PTS: 1 DIF: Comprehension

42. A drop in blood glucose concentration would likely cause a. increased release of ACh onto autonomic effectors b. decreased frequency of impulses along short preganglionic neurons c. increased frequency of autonomic impulses from the lumbar region of the spinal cord d. decreased binding of neurotransmitters to alpha-2 receptors in the pancreas e. all of the above

ANS: C PTS: 1 DIF: Comprehension

42. Which of the following is involved in the relaxation of a muscle cell? a. Synthesis of ACh by acetylcholinesterase b. Initiation of action potentials c. The troponin-tropomyosin complex slipping back into its blocking position d. Detachment of actin from tropomyosin e. T tubules actively absorbing Ca2+

ANS: C PTS: 1 DIF: Comprehension

44. Which of the following is not a characteristic of capillaries? a. thin walls b. short distance between adjacent vessels c. distensible walls d. slow blood velocity e. large total surface area

ANS: C PTS: 1 DIF: Comprehension

45. The largest total cross-sectional area is found in the a. aorta b. arterioles c. capillaries d. venules e. veins

ANS: C PTS: 1 DIF: Comprehension

47. The velocity of blood flow in capillaries is a. greater than that for arterioles b. greater than that for veins c. slow enough to favor adequate exchange of nutrients and wastes d. both a and b e. both a and c

ANS: C PTS: 1 DIF: Comprehension

54. The principle force that causes movement of fluid from the tissues into the capillaries is a. the hydrostatic pressure of the venous blood b. the hydrostatic pressure of the arterial blood c. the osmotic pressure created by the plasma proteins d. the pressure of the lymph in the tissues around the capillaries e. none of the above

ANS: C PTS: 1 DIF: Comprehension

58. Submaximal isometric contractions are important for a. moving large objects b. walking c. maintaining posture d. writing e. both a and b

ANS: C PTS: 1 DIF: Comprehension

58. Which change will increase fluid reabsorption by the capillaries? a. Decreased interstitial fluid hydrostatic pressure b. Increased capillary blood pressure c. Increased blood osmotic pressure d. Increased interstitial fluid osmotic pressure e. None of the above

ANS: C PTS: 1 DIF: Comprehension

72. Increased ____ permeability of nodal cells hyperpolarizes the SA node. a. chloride b. iodide c. potassium d. sodium e. zinc

ANS: C PTS: 1 DIF: Comprehension

75. Which of the following is not associated with an increase in stroke volume? a. increased end-diastolic volume b. increased contractility of the heart c. increased end-systolic volume d. increased preload e. increased venous return

ANS: C PTS: 1 DIF: Comprehension

86. Hypertension may be caused by all of the following except a. renal disease b. hardening of the arteries c. overactive baroreceptors d. salt imbalances e. adrenal medullary tumors

ANS: C PTS: 1 DIF: Comprehension

87. Choose the false statement about smooth muscle. a. It is under involuntary control. b. It does not have troponin. c. Its contraction is initiated neurogenically only. d. It is found in walls of hollow tube-like organs. e. It is innervated by the ANS.

ANS: C PTS: 1 DIF: Comprehension

88. Which of the following is not a compensation mechanism for blood loss? a. Fluid shift from ICF to plasma b. Venous vasoconstriction c. Lowered angiotensin II production d. Thirst e. Increased renal reabsorption of salt and water

ANS: C PTS: 1 DIF: Comprehension

97. What is responsible for initiating contraction of smooth muscle? a. Stimulation by motor neurons b. Inhibition of acetylcholinesterase c. Membrane potential drifting to threshold as a result of automatic changes in ion movement across the membrane d. Excitation of the gap junctions by a transmitter substance e. Stimulation by the autonomic nervous system

ANS: C PTS: 1 DIF: Comprehension

1. The striated appearance of skeletal muscle is due to the a. orderly arrangement of the T tubules b. orderly arrangement of the lateral sacs of the sarcoplasmic reticulum c. orderly arrangement of the thick and thin filaments into A and I bands d. orderly arrangement of the motor units e. presence of white and red muscle fibers within the muscle

ANS: C PTS: 1 DIF: Knowledge

103. Dihydropyridine receptors are most closely associated with a. neuromuscular junctions b. axon terminals c. T tubules d. myosin-binding sites e. ATPase sites

ANS: C PTS: 1 DIF: Knowledge

13. Which type of blood vessel consists of only one cell layer? a. arteriole b. artery c. capillary d. vein e. venule

ANS: C PTS: 1 DIF: Knowledge

14. The pathway that permits electrical activity to pass from cell-to-cell in myocardial tissue is the a. desmosome b. septum c. gap junction d. T-tubule e. sarcoplasmic reticulum

ANS: C PTS: 1 DIF: Knowledge

16. Identify the characteristic(s) shared by all types of muscle tissues? a. They are neurogenic. b. They have T tubules. c. They have tropomyosin. d. They attach to tendons. e. They have neuromuscular junctions.

ANS: C PTS: 1 DIF: Knowledge

18. On a normal ECG, a wave for repolarization of the atria is not recorded. Why? a. The leads are not placed in a position to pick it up. b. No repolarization of the atria occurs normally. c. It occurs simultaneously with ventricular depolarization and is masked by the QRS complex. d. It does not travel through body fluids. e. It is too small to be picked up by external recording electrodes.

ANS: C PTS: 1 DIF: Knowledge

22. Mean arterial pressure is: a. diastolic pressure + (systolic/3) b. systolic pressure + (pulse pressure/3) c. diastolic pressure + (pulse pressure/3) d. pulse pressure - (diastolic pressure/3) e. pulse pressure + (systolic pressure/3)

ANS: C PTS: 1 DIF: Knowledge

24. Acetylcholine a. opens voltage-gated Na+ channels in skeletal muscle fibers, which causes depolarization of the muscle fibers b. may decrease the permeability of the motor end plate to Na+ and K+ when combined with the receptor sites on the motor end plate c. always depolarizes skeletal muscle fibers and postganglionic neurons d. does both a and b e. does both b and c

ANS: C PTS: 1 DIF: Knowledge

26. What is the most important factor that increases blood flow through a tissue to meet that tissue's needs? a. Vasoconstriction of arteries forces more blood to flow into the tissue. b. Parasympathetic-induced vasodilation of capillaries within the tissue. c. Cellular products cause local vasodilation. d. Widespread venous vasoconstriction allows blood to dam up at the tissue level. e. All except a

ANS: C PTS: 1 DIF: Knowledge

27. Which of the following ECG waves represents ventricular repolarization? a. P wave b. QRS complex c. T wave d. PR segment e. Ventricular repolarization occurs simultaneously with atrial depolarization and consequently cannot be recorded.

ANS: C PTS: 1 DIF: Knowledge

28. As metabolic activity of an organ or tissue increases, blood flow to that organ increases. This phenomenon is known as a. pressure autoregulation b. tissue anoxia c. active hyperemia d. hypertension e. atherosclerosis

ANS: C PTS: 1 DIF: Knowledge

29. Which local chemical changes do not occur during a period of increased cell activity? a. increased CO2 b. increased acid c. decreased adenosine release d. increased K+ e. increased osmolarity

ANS: C PTS: 1 DIF: Knowledge

32. An action potential rapidly spreads to the central portions of a muscle cell by means of a. Z lines b. sarcoplasmic reticulum c. T tubules d. lateral sacs e. both a and c

ANS: C PTS: 1 DIF: Knowledge

38. The myogenic response refers to vascular smooth muscle's tendency to a. constrict when blood flow increases b. relax when blood flow increases c. constrict when stretched d. dilate when stretched e. do both b and d

ANS: C PTS: 1 DIF: Knowledge

40. The volume of blood ejected from each ventricle during a contraction is called the a. end-diastolic volume b. end-systolic volume c. stroke volume d. cardiac output e. cardiac reserve

ANS: C PTS: 1 DIF: Knowledge

41. The energy for cross bridge cycling during muscle contraction is provided by: a. acetylcholine b. Ca2+ c. ATP d. myosin e. actin

ANS: C PTS: 1 DIF: Knowledge

46. Through which vessel is the velocity of blood flow the slowest? a. aorta b. arterioles c. capillaries d. venules e. veins

ANS: C PTS: 1 DIF: Knowledge

46. What percentage of ventricular filling is normally accomplished before atrial contraction begins? a. 0% b. 20% c. 80% d. 50% e. 100%

ANS: C PTS: 1 DIF: Knowledge

5. Which of the following is the correct relationship between pressure, flow, and resistance? a. b. c. d. e.

ANS: C PTS: 1 DIF: Knowledge

64. During aerobic exercise, the primary means for ATP production in muscle fibers involves a. creatine phosphate b. fermentation c. oxidative phosphorylation d. glycolysis e. myoglobin

ANS: C PTS: 1 DIF: Knowledge

67. Which vessels contain the highest percentage of total blood volume? a. pulmonary veins b. pulmonary arteries c. systemic veins d. systemic arteries e. coronary arteries

ANS: C PTS: 1 DIF: Knowledge

68. The term systole means a. closure b. conduction c. contraction d. opening e. relaxation

ANS: C PTS: 1 DIF: Knowledge

7. Thick filaments in skeletal muscle are composed of a. actin b. troponin and tropomyosin c. myosin d. all of the above e. only b and c

ANS: C PTS: 1 DIF: Knowledge

71. Fatigue is the failure of a muscle fiber to maintain ____ as a result of previous contractile activity. a. excitability b. muscle mass c. tension d. sarcomere number e. mitochondria

ANS: C PTS: 1 DIF: Knowledge

78. A metabolic predictor of heart disease that is independent of one's cholesterol/lipid profile is a. HDL b. VLDL c. homocysteine d. methionine e. creatine

ANS: C PTS: 1 DIF: Knowledge

78. Enlargement of muscle due to weight lifting is primarily a result of a. enlargement of individual myofilaments b. hyperplasia c. increased production of actin and myosin d. increases in the number of cells e. Both b and d

ANS: C PTS: 1 DIF: Knowledge

80. Conscious initiation of muscle contraction is controlled by a. the spinal cord b. the brain stem c. the cerebral cortex d. the thalamus e. none of the above

ANS: C PTS: 1 DIF: Knowledge

80. Regulation of arterial pressure can be mediated by a reflex mechanism utilizing a pressure receptor called a ______, located in the ____. a. chemoreceptor; carotid sinus b. baroreceptor; heart c. baroreceptor; carotid sinus d. chemoreceptor; skeletal muscles e. baroreceptor; skeletal muscles

ANS: C PTS: 1 DIF: Knowledge

85. Which of the following does not occur as a compensation for hemorrhage? a. Shift of fluid from the interstitial fluid into the plasma b. Reduced urinary output c. Increased capillary permeability d. Increased cardiac output e. Increased synthesis of plasma proteins

ANS: C PTS: 1 DIF: Knowledge

9. Each I band in a skeletal muscle fiber includes a. overlapping thin and thick filaments b. thick filaments and one Z disc c. thin filaments and one Z disc d. thin filaments and two Z discs e. actin, troponin, tropomyosin and two Z discs

ANS: C PTS: 1 DIF: Knowledge

24. If the pulse pressure is 44 mm Hg and the diastolic pressure is 68 mm Hg, the systolic pressure is ____ mm Hg. a. 22 b. 24 c. 66 d. 112 e. 145

ANS: D PTS: 1 DIF: Analysis

82. When the receptor potential of the baroreceptors decreases, the cardiovascular center responds by bringing about an increase in a. stroke volume b. venous return c. total peripheral resistance d. all of the above e. only a and b

ANS: D PTS: 1 DIF: Analysis

11. Cross bridges a. bind to actin during muscle contraction b. are globular heads made of myosin c. do not bend during muscle contraction d. have characteristics a and b e. have characteristics b and c

ANS: D PTS: 1 DIF: Comprehension

12. Order the following muscle cell components from larger to smaller 1. troponin 2. myofibril 3. sarcomere 4. thin filament 5. muscle fiber a. 3, 4, 1, 5, 2 b. 1, 2, 3, 5, 4 c. 5, 4 ,3 , 1, 2 d. 5, 2, 3, 4, 1 e. 3, 4, 5, 2, 1

ANS: D PTS: 1 DIF: Comprehension

13. Choose a correct sequence of blood flow during one pass through the heart and lungs (some steps may have been omitted): a. Right atriumbicuspid valvepulmonary vein b. Aortic valveright ventriclelung c. Lungpulmonary arteryleft atrium d. Right ventriclebicuspid valveaortic valve e. None of the above sequences are correct

ANS: D PTS: 1 DIF: Comprehension

14. Sympathetic stimulation ____ heart rate and ____ the motility in the digestive tract. a. does not affect; decreases b. decreases; decreases c. decreases; increases d. increases; decreases e. increases; increases

ANS: D PTS: 1 DIF: Comprehension

17. The _____ phase of the action potential in _____ cells is due to a _____. a. rising, autorhythmic cells, rapid Ca2+ influx b. rising, contractile cells, rapid Na+ influx c. plateau, contractile cells, slow Ca2+ influx d. All of the above correctly complete the sentence. e. Only b and c correctly complete the sentence.

ANS: D PTS: 1 DIF: Comprehension

19. Which of the following criteria must be met for the heart to function efficiently? a. Excitation and contraction of each heart chamber should be coordinated to ensure efficient pumping. b. The atria should be excited and contract before the onset of ventricular contraction to ensure that ventricular filling is complete. c. The right side of the heart should contract first to ensure that oxygenated blood is delivered to the heart before the left side contracts. d. Both a and b e. Both b and c

ANS: D PTS: 1 DIF: Comprehension

23. Which of the following are involved in the regulation of cross bridge attachment activity? a. calcium ions b. troponin c. tropomyosin d. all of the above e. only b and c

ANS: D PTS: 1 DIF: Comprehension

24. Which of the following is not occurring at the same time when the QRS complex appears on an ECG? a. depolarization of Purkinje fibers b. depolarization of the ventricles c. repolarization of the atria d. depolarization of internodal pathways e. All of the above are occurring at the same time

ANS: D PTS: 1 DIF: Comprehension

28. During excitation-contraction coupling, a. the action potential travels down the T tubules b. Ca2+ is released from the sarcoplasmic reticulum c. Ca2+ is taken up by the sarcoplasmic reticulum d. both a and b occur e. both a and c occur

ANS: D PTS: 1 DIF: Comprehension

33. Extrinsic control of arteriolar radius is a. accomplished primarily by the sympathetic nervous system b. important in the regulation of arterial blood pressure c. sometimes overridden by local adjustments d. all of the above e. only a and b

ANS: D PTS: 1 DIF: Comprehension

36. The refractory period of cardiac muscle a. lasts almost as long as the contraction period b. is much longer than the refractory period in skeletal muscle c. prevents tetanic contraction of the heart to occur to ensure smooth, coordinated ejection of blood from the ventricles d. is important for all of the above reasons e. is important for only reasons a and b

ANS: D PTS: 1 DIF: Comprehension

38. Myasthenia gravis a. is an autoimmune disease b. occurs when axons are unable to release adequate amounts of acetylcholine c. can be treated with a drug that temporarily inhibits acetylcholinesterase d. has characteristics a and c e. has none of the above characteristics

ANS: D PTS: 1 DIF: Comprehension

4. Vasoconstriction a. refers to a decrease in the radius of a vessel b. of an arteriole decreases blood flow through that vessel c. of a vein increases blood flow through that vessel d. is defined in "a" and causes "b" e. is defined in "a" and causes "c"

ANS: D PTS: 1 DIF: Comprehension

41. Which factor would reduce total peripheral resistance? a. adrenal medulla hormones b. angiotensin II c. red blood cell concentration d. anaphylactic shock e. cardiovascular center activity

ANS: D PTS: 1 DIF: Comprehension

42. Which factor(s) would decrease cardiac output? a. increased venous return b. decreased vagal stimulation of the heart c. increased preload d. decreased preload e. Both a and c

ANS: D PTS: 1 DIF: Comprehension

44. Which of the following is involved in muscle relaxation? a. Acetylcholinesterase removes ACh and the muscle cell returns to resting potential. b. Ca2+ is actively taken up by the lateral sacs when there is no longer an action potential. c. The cross bridges pull the filaments back to their original resting positions. d. Both a and b e. Both b and c

ANS: D PTS: 1 DIF: Comprehension

51. The process of ultrafiltration a. is movement of protein-free plasma from the capillaries into the interstitial fluid b. occurs when capillary blood pressure plus interstitial fluid osmotic pressure exceed blood-osmotic pressure plus interstitial fluid hydrostatic pressure c. occurs when capillary blood pressure plus plasma osmotic pressure exceed interstitial fluid hydrostatic pressure plus interstitial fluid osmotic pressure d. is both a and b e. is both a and c

ANS: D PTS: 1 DIF: Comprehension

52. Picking up a book at a constant speed requires that a. muscle tension be equal to the book's weight b. the muscle perform an eccentric contraction c. the muscle perform an isometric contraction d. the muscle perform a concentric contraction e. both a and d occur

ANS: D PTS: 1 DIF: Comprehension

9. A lumen that contains blood with a comparatively higher concentration of oxygen is in the a. right ventricle b. inferior vena cava c. pulmonary artery d. pulmonary vein e. coronary veins

ANS: D PTS: 1 DIF: Comprehension

10. The larger arteries assist with systemic blood flow to tissues by a. contracting their endothelial layer b. using valves to propel the blood c. providing blood directly to large veins d. elastic recoil of their walls e. continuous vasoconstriction

ANS: D PTS: 1 DIF: Knowledge

11. The right half of the heart pumps blood through the ____ circuit and the left half pumps blood through the ____ circuit. a. systolic; diastolic b. coronary; pulmonary c. systemic; pulmonary d. pulmonary; systemic e. systemic; coronary

ANS: D PTS: 1 DIF: Knowledge

13. The sympathetic nervous system a. is always excitatory for smooth muscle b. innervates only tissues concerned with protecting the body against challenges from the outside environment c. dominates in rest-and-digest situations d. contains cholinergic and adrenergic fibers e. stimulates only effectors that are dually innervated

ANS: D PTS: 1 DIF: Knowledge

14. The region between two Z lines is a a. muscle fiber b. myofibril c. myofilament d. sarcomere e. sarcoplasmic reticulum

ANS: D PTS: 1 DIF: Knowledge

15. Organs that recondition the blood a. receive disproportionately large percentages of the cardiac output b. can withstand temporary reductions in blood flow much better than organs that do not recondition the blood c. must receive a constant blood supply in order to maintain homeostasis d. have characteristics a and b e. have characteristics b and c

ANS: D PTS: 1 DIF: Knowledge

15. What component of the cardiac conduction system distributes electrical signals directly through the papillary muscles? a. AV nodes b. AV bundle c. bundle of His d. Purkinje fibers e. SA node

ANS: D PTS: 1 DIF: Knowledge

19. The neurotransmitter at a neuromuscular junction is a. acetylcholine b. the same as the transmitter substance at parasympathetic postganglionic nerve endings c. the same as that released by all preganglionic fibers d. all of the above e. only a and b

ANS: D PTS: 1 DIF: Knowledge

2. Which valve(s) prevent(s) regurgitation of blood from a ventricle to an atrium? a. Tricuspid b. Mitral c. Pulmonary d. Both a and b e. Both b and c

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20. Select the correct statement about veins. a. Their walls are highly muscular. b. Their walls consist of one layer of cells. c. There are only about 40 large ones in the body. d. They serve as a blood reservoir. e. They transport blood away from the heart.

ANS: D PTS: 1 DIF: Knowledge

22. Which organ is not innervated by the parasympathetic division? a. blood vessels b. intestines c. eye d. liver e. erectile tissues

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23. The direction of impulses through the conduction system of the heart is normally a. AV nodeSA nodebundle of HisPurkinje fibers b. AV nodebundle of HisSA node-Purkinje fibers c. bundle of HisAV nodePurkinje fibersSA node d. SA nodeAV nodebundle of HisPurkinje fibers e. SA nodebundle of HisPurkinje fibersAV node

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25. Which type of receptor binds norepinephrine on cardiac muscle, thus increasing cardiac activity? a. cholinergic b. nicotinic c. alpha d. beta-1 e. beta-2

ANS: D PTS: 1 DIF: Knowledge

3. Semilunar valves prevent backflow of blood from a. the ventricles to the atria b. the atria to the ventricles c. the ventricles to the arterial trunks d. the arterial trunks to the ventricles e. none of the above

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32. Select the CNS structure(s) that can influence autonomic activity. a. medulla b. hypothalamus c. spinal cord d. All of the above e. Only a and b

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34. During strenuous exercise, blood flow increases to a. the heart because of local control factors b. the brain because of reflex control factors c. the skeletal muscles because of local control factors d. both a and c e. none of the above; blood flow remains fairly constant to these organs

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36. Select the correct statement about the neuromuscular junction. a. AChE activity is absent here. b. It involves presynaptic neurons of the autonomic nervous system. c. It is a junction between two neurons. d. It is always excitatory. e. The axon terminals do not store neurotransmitters.

ANS: D PTS: 1 DIF: Knowledge

37. Each of the following local factors produces the relaxation of arteriolar smooth muscle except increased a. acid b. carbon dioxide c. osmolarity d. oxygen e. potassium

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37. Foot proteins a. span the gap between a lateral sac of the sarcoplasmic reticulum and a T tubule b. are believed to serve as Ca2+ channels c. bind to and pull the thin filaments inward toward the A band's center during contraction d. have characteristics a and b e. are none of the above

ANS: D PTS: 1 DIF: Knowledge

40. During exercise, blood flow to the _____ remains fairly constant. a. kidney b. heart c. skin d. brain e. liver

ANS: D PTS: 1 DIF: Knowledge

40. Which effector is not dually innervated? a. salivary glands b. urinary bladder c. pancreas d. radial muscle of iris e. bronchioles in lungs

ANS: D PTS: 1 DIF: Knowledge

51. The second heart sound is produced by the a. opening of the AV valves b. closing of the AV valves c. opening of the semilunar valves d. closing of the semilunar valves e. blood rushing through the AV valves during diastole, creating a turbulent flow

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52. The first heart sound a. occurs when the AV valves open b. occurs when the semilunar valves close c. signals the onset of ventricular diastole d. occurs when the AV valves close, and signals the onset of ventricular systole e. occurs when the semilunar valves close, and signals the onset of ventricular diastole

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56. During an isometric contraction, the muscle a. maintains a constant tension b. shortens c. moves a body part d. maintains a constant length e. tension is greater than the load

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59. An insufficient AV valve a. fails to open completely b. is not connected to chordae tendineae c. produces a gurgling diastolic murmur d. allows blood to backflow into a ventricle during diastole e. allows blood to leak into the pulmonary artery during right ventricular diastole

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62. Energy sources available to form ATP in muscle fibers in the absence of oxygen include a. creatine phosphate b. chemiosmosis c. glycolysis d. creatine phosphate and glycolysis e. chemiosmosis and glycolysis

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64. Which of the following is not a function of the lymphatic system? a. Defense against disease b. Return of fluid to the circulatory system c. Transport of fat molecules d. Regulation of sodium balance e. Return of proteins to the circulatory system

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65. Myoglobin a. can store small amounts of O2 b. increases the rate of O2 transfer from the blood into muscle fibers c. is abundant in fast-glycolytic fibers d. can perform a and b e. has characteristics a and c

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66. Which vessels can act as a blood reservoir by adjusting their total capacity to accommodate variations in blood volume? a. lymph vessels b. arterioles c. capillaries d. veins e. lymph vessels and veins

ANS: D PTS: 1 DIF: Knowledge

69. Parasympathetic innervation to the heart a. involves the vagus nerve b. decreases the rate at which the pacemaker potential reaches threshold c. decreases the strength of ventricular contraction d. is characterized by all of the above e. is characterized by only a and b

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71. Select the incorrect statement about rheumatic fever. a. It causes a heart murmur. b. It is an autoimmune disease. c. It is triggered by a streptococcus bacterium. d. The heart conduction system is disrupted. e. The heart valves become inflamed and scarred.

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72. The two determinants of mean arterial pressure are ____ and ____. a. stroke volume; compliance of vessel walls b. heart rate; stroke volume c. heart rate; end-diastolic volume d. cardiac output; total peripheral resistance e. None of the above

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75. When blood pressure becomes elevated above normal, a. the carotid and aortic baroreceptors increase their rate of firing b. sympathetic stimulation of blood vessels increases c. arteriolar vasoconstriction occurs as a compensatory response d. parasympathetic stimulation of the heart increases e. all of the above occur

ANS: D PTS: 1 DIF: Knowledge

76. Short-term adjustments in blood pressure are mediated by a. baroreceptor reflexes b. changes in cardiac output c. renal activity d. both a and b e. both b and c

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76. Vasodilation of coronary arteries is induced by a. adenosine b. nitroglycerin c. nitric oxide d. all of the above e. only a and b

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77. The cardiac muscle a. extracts oxygen and nutrients from the blood within its chambers b. receives its blood supply primarily during ventricular systole when blood is forced into coronary arteries c. receives its blood supply directly from the pulmonary circulation as all of this blood passes through the coronary circulation d. receives most of its blood supply during ventricular diastole by means of coronary arteries e. does not receive blood in any of the ways mentioned above

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84. The stretch receptors in the central portion of the muscle spindle can be activated by a. passive stretch of the whole muscle, including stretch of the muscle spindle b. contraction of the end portions of the muscle spindle c. gamma motor neuron stimulation of the muscle spindle d. all of the above e. none of the above

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88. Cardiac muscle tissue a. has well developed sarcoplasmic reticulum b. has fast myosin ATPase activity c. contracts only when stimulated neurogenically d. has gap junctions e. stores calcium in its T tubules

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90. Select the correct statement regarding smooth muscle. a. It composes the walls of the heart. b. It is absent in the walls of hollow organs. c. Its cells are multinucleated. d. Its cells are spindle-shaped. e. Its cells lack actin and myosin.

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90. The carotid sinuses and aorta contain receptors that are sensitive to changes in a. blood pressure b. acid level in the blood c. oxygen level in the blood d. all of the above e. only a and c

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93. Which of the following muscle types are myogenic? a. cardiac muscle b. single-unit smooth muscle c. multi-unit smooth muscle d. Both a and b e. Both b and c

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94. Multi-unit smooth muscle is a. neurogenically activated b. under ANS control c. found in the iris of the eye d. all of the above e. none of the above

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76. With the type of lever system exemplified by flexion of the elbow joint, when an object is held in the hand, the a. power arm of the lever is the distance between the elbow joint and the insertion of the biceps muscle b. load arm of the lever is the distance between the elbow joint and the hand c. velocity and distance moved by the hand is amplified at the expense of the biceps muscle having to exert considerably greater force than the actual load that is moved d. answers a, b, and c are correct e. answers a and b are the only correct answers

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101. A functional syncytium of cardiac muscles cells means that they a. are striated b. exhibit muscle tone c. have a short refractory period d. lack the stimulation of a pacemaker e. work as a unit mechanically and electrically

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2. Muscle fibers develop tension by a. contraction of sarcomeres b. shortening c. the pushing of myosin by actin d. all of the above e. both a and b

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23. The neuromuscular junction a. is the junction between a motor neuron and a skeletal muscle fiber b. transmits an action potential between the nerve cell and muscle cell on a one-to-one basis c. may produce either an EPSP or an IPSP on the motor end plate d. has all of the above characteristics e. has characteristics a and b

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29. What would occur if ACh was not removed from the nicotinic receptors on skeletal muscle cells? a. The cell would relax. b. The cell would repolarize with the opening of chloride channels. c. The cell would remain contracted until fatigued. d. Sodium would continue to move into the cell, causing excitation. e. Both c and d would occur.

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41. Identify the true statement(s): a. NE causes most blood vessels to constrict. b. ACh causes the pancreas to release glucagon c. Binding of a neurotransmitter to a beta-1 receptor on the heart would result in a faster heart rate. d. Both a and b are true e. Both a and c are true

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43. A lack of ATP in a contracted skeletal muscle cell would most likely cause a. cross bridges to detach from actin b. the sarcomeres to remain shortened c. an inability to relax d. both a and c e. both b and c

ANS: E PTS: 1 DIF: Comprehension

44. Which is true when your sympathetic nervous system is more active? a. The SA node depolarizes more rapidly. b. The myocardium repolarizes more frequently during one minute. c. More Ca2+ becomes available and causes more forceful heart contractions. d. Norepinephrine is stimulating the heart. e. All of the above are true.

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47. In twitch summation, the muscle fiber a. is stimulated again before the fibers returns to resting potential. b. is stimulated again before it completely returns to resting position. c. contracts stronger but stronger action potentials do not occur. d. experiences a and b e. experiences b and c

ANS: E PTS: 1 DIF: Comprehension

47. Vagal influences on the heart result in a. enhanced calcium permeability at the SA node b. enhanced potassium permeability at the SA node c. less frequent depolarization of the SA node d. both a and b e. both b and c

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48. Twitch summation a. is a means by which gradation of muscle contraction may be accomplished b. results from the additional release of Ca2+ within the cytosol of muscle fibers c. results from increasing the frequency at which motor units are firing within a muscle d. results from more cross bridges binding to actin within muscle fibers e. has all of the above characteristics

ANS: E PTS: 1 DIF: Comprehension

52. Reabsorption in capillaries occurs a. when blood osmotic pressure plus blood hydrostatic pressure exceed outward-driving forces. b. when blood osmotic pressure plus interstitial fluid osmotic pressure exceed outward-driving forces. c. when blood hydrostatic pressure plus blood osmotic pressure is less than inward-driving forces. d. under conditions a and c e. None of these

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59. Which of the following alterations could lead to edema? a. A fall in capillary blood pressure b. A fall in the concentration of plasma proteins c. Blocked lymph vessels d. Both a and b e. Both b and c

ANS: E PTS: 1 DIF: Comprehension

61. If the load on a muscle is increased, eventually a load will be reached at which the velocity of shortening becomes zero. At this point, the muscle contraction is referred to as a. concentric b. eccentric c. isotonic d. isokinetic e. isometric

ANS: E PTS: 1 DIF: Comprehension

63. Which of the following conditions might be the cause of edema? a. Extensive burns b. Congestive heart failure c. Blocked lymphatics d. Increased venous pressure e. All of the above

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66. Select the correct statement about the summation of simple twitches. a. They can occur because of the long duration of the action potential in a muscle fiber. b. They reduce the tension in a muscle. c. They result from the slow stimulation of a muscle fiber. d. The effect is unrelated to the refractory periods of action potentials. e. The twitches resulting from separate action potentials.

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67. During heart failure, a. the Frank-Starling curve shifts to the left b. the heart pumps out a smaller stroke volume than normal for a given EDV c. a compensatory increase in sympathetic activity increases the contractility of the heart to normal in the early stages of the disease d. both a and c occur e. both b and c occur

ANS: E PTS: 1 DIF: Comprehension

8. The parasympathetic nervous system a. has long preganglionic fibers that end on terminal ganglia, which lie in or near the effector organ b. dominates in quiet, relaxed situations c. releases a postganglionic neurotransmitter that binds with muscarinic receptors d. has neurons that display nicotinic receptors e. has all of the above characteristics

ANS: E PTS: 1 DIF: Comprehension

102. Which one of the following statements about cardiac muscle is incorrect? a. It contains gap junctions. b. It is found only in the heart c. It is self-excitable. d. It is striated with intercalated disks. e. It lacks tropomyosin.

ANS: E PTS: 1 DIF: Knowledge

11. Which is not true about blood pressure? a. It is maximal during ventricular systole. b. It decreases as blood moves farther away from the heart. c. It increases with increasing resistance. d. It decreases with increasing vessel diameter. e. It can be increased by direct parasympathetic activity.

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16. The motor end plate a. contains receptor sites that are capable of binding curare b. contains acetylcholinesterase c. experiences an increase in permeability to cations when combined with acetylcholine d. contains nicotinic receptors e. exhibits all of the above characteristics

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17. The functional unit of skeletal muscle a. is the smallest contractile component of a muscle fiber b. is the area between two Z lines c. is the sarcomere d. contains only one A band e. exhibits all of the above characteristics

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17. The major function of the arterioles is to a. regulate flow of blood through capillary beds b. distribute the cardiac output to tissues c. serve as a pressure reservoir d. convert the intermittent flow from the heart to a steady outflow e. perform functions a and b

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18. Because of their elasticity, arteries act as a(n) ____ for maintaining blood flow during diastole. a. cardiac reserve b. venous reserve c. arterial capacitance d. lymphatic reserve e. pressure reservoir

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2. Resistance a. is a measure of the hindrance to blood flow through a vessel caused by friction between the moving fluid and stationary vascular walls b. is doubled when the radius of the vessel is reduced by one-half c. increases 16-fold when the radius of the vessel is reduced by one-half d. is both a and b e. is both a and c

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2. The overall functioning of the ANS contributes to a. conservation of energy resources when stress levels are low b. mobilization of energy reserves when stress levels are high c. suppression of non-vital activities when stress levels are high d. homeostasis e. all of the above

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25. The H zone a. is the area within the middle of the A band where the thin filaments do not reach b. shortens or disappears during contraction c. contains only thick filaments d. does not contain cross bridges e. is all of the above

ANS: E PTS: 1 DIF: Knowledge

25. The fastest rate of autorhythmicity is normally carried out by the a. AV bundle b. AV node c. bundle of His d. Purkinje fibers e. SA node

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29. Extrasystole of the heart means that it a. beats too slowly b. fills with too much blood c. has a complete block d. loses blood e. produces a premature beat

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31. Fibrillation is the a. backflow of blood throughout the heart b. coordinated function of nodal cells c. failure of the heart valves to function d. flow of blood through the heart's fibrous skeleton e. uncoordinated excitation and contraction of cardiac cells

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31. The T tubules a. store Ca2+ b. provide a means of rapidly transmitting ACh to the central portions of the muscle fiber c. provide attachment sites for ACh d. perform b and c e. do not do any of the above

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35. Arterioles in which of the following receive stimulation from parasympathetic neurons? a. liver b. kidney c. brain d. heart e. clitoris

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37. Atropine is an antagonist of ACh and works by a. selectively binding to nicotinic receptors b. selectively binding to muscarinic receptors c. blocking the binding of ACh d. both a and b e. both b and c

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38. Which statement is incorrect about cross bridges? a. They are globular myosin heads that protrude from the thick filaments. b. They bend during muscle contraction. c. They attach and detach from actin during muscle contraction. d. They are not found in the I band. e. They bind with troponin during contraction.

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39. Which of the following does not cause arteriolar vasodilation? a. decreased sympathetic stimulation b. local decrease in O2 c. histamine d. application of heat e. myogenic response

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4. Myosin is a. found in the I band b. attached to tropomyosin c. a regulatory protein d. all of the above e. none of the above

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40. Cross bridge interaction between actin and myosin in skeletal muscle is directly blocked by a. acetylcholine b. triads c. Z lines d. calcium e. tropomyosin

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44. Activation of ______ receptors usually brings about _______. a. alpha-1, excitation b. alpha-2, inhibition c. beta-1, excitation d. beta-2, inhibition e. All of the above are correct choices.

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45. Whole muscle tension depends on all of the following except a. number of muscle fibers contracting b. tension produced by each contracting fiber c. extent of motor-unit recruitment d. frequency of stimulation e. the proportion of each motor unit used at any given time

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48. A condition in which the heart is contracting in an uncontrolled, rapid, and irregular manner a. is heart block b. is fibrillation c. can be treated with administration of an electrical current d. is none of the above e. is both b and c

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49. The heart is a. sympathetically innervated via cardiac nerve fibers b. parasympathetically innervated by vagus nerve fibers c. only partly innervated by the somatic nervous system d. innervated by only the sympathetic division of the autonomic nervous system e. both a and b

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5. Actin a. has ATPase activity b. are spherical c. forms a helical chain that forms the main structural component of the thin filaments d. has characteristics a and b e. has characteristics b and c

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50. The movements of fluid across the capillary wall is influenced by a. capillary blood pressure b. interstitial fluid hydrostatic pressure c. plasma osmotic pressure d. interstitial fluid osmotic pressure e. all of the above

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51. Based on the length-tension relationship, a. stretching a skeletal muscle 30% longer than the lo results in a greater contraction b. varying the amount of overlap of thick and thin filaments does not greatly affect contraction force as long as tension remains the same c. more tension develops if a muscle is 30% shorter than its resting length d. muscle tension remains the same as long as the muscle's length is not more than 30% of the resting length. e. a resting muscle that is shorter or longer than its lo will generate less tension at the onset of contraction.

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54. The origin of a muscle is its a. main, thickest part b. middle, thinner part c. movable end of attachment d. source of development in the fetus e. stationary end of attachment

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55. During an isotonic contraction, a. sarcomeres do not shorten in the muscle b. movement does not occur inside the muscle c. the muscle does not change length d. the muscle's tension does not overcome a load e. the muscle's tension remains constant

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6. Blood flow is affected by a. pressure differences b. the viscosity of the blood c. the amount of friction in the blood vessels d. the length and diameter of the blood vessels e. all of the above

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65. The veins a. act as high-resistance passageways for blood flow from the tissues to the heart b. can serve as a blood reservoir by adjusting their total capacity to accommodate variations in blood volume c. contain one-way valves that prevent backflow as blood moves toward the heart d. have characteristics a and b e. have characteristics b and c

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68. Fast-glycolytic (type IIx) muscle fibers a. have high myosin-ATPase activity b. can carry out oxidative phosphorylation c. fatigue rapidly d. contain myoglobin e. have all of the above characteristics

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7. Parasympathetic postganglionic fibers a. arise from the ganglion chain located along either side of the spinal cord b. are cholinergic c. secrete a chemical messenger that binds to muscarinic receptors d. have characteristics a and b e. have characteristics b and c

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70. Sympathetic stimulation of the heart a. increases the heart rate b. increases the heart's contractility c. shifts the Frank-Starling curve to the left d. involves the release of norepinephrine e. causes all of the above

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71. Which of the following factors aids venous return to the heart? a. Sympathetic stimulation of capillaries b. Skeletal muscle pump squeezing blood through veins c. Respiratory pump providing a pressure gradient between the lower and chest veins d. Both a and b e. Both b and c

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72. Muscular fatigue can be caused by a. lactic acid accumulation b. depletion of ATP c. depletion of ACh d. only two of the above e. a, b, or c

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73. The parasympathetic nervous system has little effect on ____ activity. a. atrial b. AV node c. heart rate d. SA node e. ventricular

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73. Which of the following would promote an increase in blood pressure? a. epinephrine b. aldosterone c. angiotensin II d. water retention e. All of the above

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77. Which statement below is characteristic of most of the body's lever systems? a. They work at mechanical advantage. b. They work at a mechanical disadvantage. c. Muscles must exert greater forces than the load. d. Both a and b e. Both b and c

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79. Receptors that detect changes in the blood pressure are located in a. the carotid sinus b. the aorta c. the hypothalamus d. all of the above e. both a and b

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83. Intrafusal muscle fibers a. are supplied by alpha motor neurons b. are found within muscle spindles c. contain sensory nerve endings that are activated by stretch d. have characteristics a and c e. have characteristics b and c

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84. _______ refers to a chronic state of increased arterial pressure. a. Shock b. Congestive heart failure c. Pulmonary edema d. Angina pectoris e. Hypertension

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86. Calcium turns on cross bridges by physically repositioning the troponin-tropomyosin complex to uncover the actin cross-bridge binding sites in a. skeletal muscle b. cardiac muscle c. smooth muscle d. striated muscle e. all of the above except c

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87. Shock may develop from a. loss of blood b. low cardiac output c. decreased venous return d. excessive vasodilation e. all of the above

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89. Varicose veins develop mainly from the incompetent function of the a. connective tissue lining b. endothelium c. lack of a pressure gradient d. smooth muscle e. valves

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9. The sympathetic nervous system a. releases NE from most of its preganglionic neurons b. has some postganglionic fibers that release acetylcholine c. has preganglionic neurons that originate in the thoracic and lumbar regions of the spinal cord d. has characteristics a and b e. has characteristics b and c

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91. ____ is not required for contraction of smooth muscle fibers. a. Calcium b. Calmodulin c. Phosphate d. ATP e. Troponin

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95. Single-unit smooth muscle a. contains an abundance of gap junctions b. is self-excitable c. is found in the walls of the digestive, reproductive, and urinary tracts and small blood vessels d. forms functional syncytia e. has all of the above characteristics

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