Chapter 19 The Heart Questions – Flashcards

6) Which of the following carry oxygen-poor blood. a. Pulmonary veins and vena cavae. b. Aorta and pulmonary veins. c. Aorta and vena cavae. d. Venae cavae and pulmonary arteries. e. Pulmonary veins and pulmonary arteries.

7) Which of the following belong to the pulmonary circuit. a. Aorta and venae cavae. b. Aorta and pulmonary veins. c. Pulmonary arteries and venae cavae. d. Venae cavae and pulmonary veins e. Pulmonary arteries and pulmonary veins.

8) _______ is the most superficial layer enclosing the heart. a. Parietal pericardium. b. Visceral pericardium. c. Endocardium. d. Epicardium. e. Myocardium.

9) Pericardial fluid is found between. a. The visceral pericardium and the myocardium. b. The visceral pericardium and the epicardium. c. The parietal and visceral membranes. d. Myocardium and endocardium. e. Epicardium and myocardium.

10) The ___________ performs the work of the heart. a. Fibrous skeleton. b. Pericardial cavity. c. Endocardium. d. Myocardium. e. Epicardium.

11) The tricuspid valve located between the. a. The right atrium and the left atrium. b. The right atrium and right ventricle. c. The right atrium and the left ventricle. d. The left atrium and the left ventricle. e. The left ventricle and the right ventricle.

12) Oxygen-poor blood passes through. a. The right AV (tricuspid) valve and pulmonary valve. b. The right AV (tricuspid) valve only. c. The left AV (bicuspid) valve and aortic valve. d. The left AV (bicuspid) valve only. e. The pulmonary and aortic valves.

13) Opening and closing of the heart valves is caused by. a. Breathing. b. Gravity. c. Valves contracting and relaxing. d. Osmotic gradients. e. Pressure gradients.

14) After entering the right atrium, the furthest a red blood cell can travel is the. a. Right ventricle. b. Pulmonary trunk. c. superior vena cava. d. ascending aorta. e. Left atrium.

15) Obstruction of the ____ will cause a more severe myocardial infarction (MI) than the obstruction of any of the others. a. Left marginal vein. b. Left coronary artery (LCA). c. posterior interventricular vein. d. anterior interventricular branch. e. Circumflex branch.

16) Cardiac muscle shares this feature with skeletal muscle. a. Cardiac muscle fibers have striations. b. All cardiac muscle fibers depend on nervous stimulation. c. Cardiac muscle fibers communicate by electrical (gap) junctions. d. Cardiac muscle fibers are joined end to end by intercalated discs. e. Some cardiac muscle fibers are autorhythmic.

17) The ________________ is the pacemaker that initiates each heart beat. a. Sympathetic division of the nervous system. b. autonomic nervous system. c. sinoatrial (SA) node. d. Atrioventricular (AV) node.

18) All of the following are part of the cardiac conduction system except. a. The sinoatrial node. b. The tendinous cords. c. the atrioventricular node d. The atrioventricular bundle (bundle of His). e. The Purkinje fibers.

19) These are features of cardiac muscle fibers except a. They depend almost exclusively on aerobic respiration. b. They are rich in glycogen. c. They have huge mitochondria. d. They are very rich in myoglobin. e. They have about the same endurance as skeletal muscle fibers.

20) This is the correct path of an electrical excitation from the pacemaker to a cardiocyte in the left ventricle (LV). a. SA node, atrioventricular bundle, AV node. Purkinje fibers, cardiocyte in LV. b. AV node, Purkinje fibers, atrioventricular bundle, SA node, cardiocyte in LV. c. AV node, SA node, atrioventricular bundle, Purkinje fibers, cardiocyte in LV. d. SA node, AV node, atrioventricular bundle, Purkinje fibers, cardiocyte in LV. e. SA node, AV node, purkinje fibers, atrioventricular bundle, cardiocyte in LV

21) The pacemaker potential is a result of. a. A. Na+ inflow. b. B. Na+ outflow. c. C. K+ inflow. d. D. K+ outflow. e. E. Ca2+ inflow.

22) The plateau in the action potential of cardiac muscle results from the action of a. Na+ inflow. b. K+ inflow. c. K+ outflow. d. Fast Ca2+ channels. e. Slow Ca2+ channels.

23) The long plateau in the action potential observed in cardiocytes is probably related with ____ staying longer in their cytosol. a. Na+ . b. K+. c. Ca2+. d. Cl- . e. Na+, K+, and Ca2+.

24) Cells of the sinoatrial node ____________ during the pacemaker potential. a. Depolarize fast. b. Depolarize slow. c. Repolarize slowly. d. Repolarize fast.

25) Any abnormal cardiac rhythm is called. a. Ectopic focus. b. Sinus rhythm. c. Nodal rhythm. d. Heart block. e. Arrhythmia.

26) If the sinoatrial node is damaged, the heart will likely beat at a. Less than 10 bpm. b. 10 to 20 bpm. c. 20 to 40 bpm. d. 40 to 50 bpm. e. 70 to 80 bpm.

27) The _______ provides most of the Ca2+ needed for myocardial contraction. a. extracellular fluid. b. mitochondria. c. Sarcoplasmic reticulum. d. Golgi apparatus. e. Cytoskeleton.

28) Atrial systole begins. a. Immediately before the P wave. b. Immediately after the P wave. c. During the Q wave. d. During the S-T segment. e. Immediately after the T wave.

29) Atrial depolarization causes. a. The P wave. b. The QRS complex. c. The T wave. d. The first heart sound. e. The quiescent period.

30) The long absolute refractory period of cardiocytes. a. Ensures a short twitch. b. Prevents tetanus. c. Makes the heart prone to arrhythmias. d. Prevents the occurrence of ectopic focuses. e. Causes the pacemaker potential.

31) When the left ventricle contracts, the _____ valve closes and the _____ valve opens. a. Bicuspid; pulmonary. b. Tricuspid; pulmonary. c. Tricuspid; aortic. d. Mitral; aortic. e. Aortic; pulmonary.

32) Isovolumetric contraction occurs during the _________ of the electrocardiogram. a. P wave. b. P-Q segment. c. R wave. d. S-T segment. e. T wave.

33) During isovolumetric contraction, the pressure in the ventricles. a. Falls rapidly. . b. Rises rapidly. c. Remains constant. d. Rises and then falls. e. Falls and then rises.

34) Mitral valve prolapse generates a murmur associated with _____ heart sound that occurs when the ____. a. S1; atria contract. b. S2; atria relax. c. S1; ventricles contract. d. S2; ventricles relax. e. S1; ventricles relax.

35) The correct sequence of events of the cardiac cycle is a. Ventricular filling, isovolumetric contraction, isovolumetric relaxation, ventricular ejection. b. Ventricular filling, isovolumetric relaxation, isovolumetric contraction, ventricular ejection. c. Ventricular filling, ventricular ejection, isovolumetric contraction, isovolumetric relaxation. d. Ventricular filling, isovolumetric relaxation, ventricular ejection, isovolumetric contraction. e. Ventricular filling, isovolumetric contraction, ventricular ejection, isovolumetric relaxation.

36) Most of the ventricle filling occurs a. During atrial systole. b. When the AV valve is closed. c. During ventricular systole. d. During atrial diastole. e. During isovolumetric contraction.

37) Congestive heart failure of the right ventricle a. Can cause pulmonary edema. b. Can cause systemic edema. c. Increases the ejection fraction of the right ventricle. d. Reduces the ejection fraction of the left ventricle. e. Increases cardiac output in both ventricles.

38) Mitral stenosis a. Can cause pulmonary edema. b. Can cause systemic edema. c. Increase ejection fraction of the left ventricle. d. Increases cardiac output in left ventricle.

39) Assume that the left ventricle of a child's heart has an EDV=90mL, and ESV=60mL, and a cardiac output of 2,400 mL/min. His SV and HR are a. SV=30 mL/beat, HR=80 bpm. b. SV=40 mL/beat, HR=60 bpm. c. SV=80 mL/beat, HR=30 bpm. d. SV=150 mL/beat, HR=16 bpm. e. SV=16 mL/beat, HR=150 bpm.

40) Which of the following increases stroke volume. a. High arterial blood pressure. b. Negative inotropic agents. c. Increased venous return. d. Increased afterload. e. Dehydration.

41) The volume of blood ejected by each ventricle in one minute is called a. The cardiac reserve. b. The preload. c. The afterload. d. The stroke volume. e. The cardiac output.

42) Cardioinhibitory centers in the _______ receive input from __________. a. Cortex; proprioceptors in the muscles. b. thalamus; chemoreceptors in the medulla oblongata c. Hypothalamus; proprioceptors in the joints. d. Medulla oblongata; chemoreceptors in the aortic arch. e. Pons; baroreceptors in the internal carotid.

43) The Frank-Starling law of the heart states that stroke volume is proportional to a. The end-systolic volume. . b. The end-diastolic volume. c. The afterload. d. The heart rate. e. Contractility.

44) Blood returning to the heart from the systemic circuit first enters the a. Left atrium. b. Left ventricle. c. Conus arteriosus. d. Right ventricle. e. Right atrium.

45) Blood returning to the heart from the pulmonary circuit first enters the a. Left atrium. b. Right ventricle. c. Right atrium. d. Left ventricle. e. Conus arteriosus.

46) The expandable extension of the atrium is the a. Ventricle. b. Auricle. c. Coronary sulcus. d. Interatrial septum. e. Coronary sinus.

47) The coronary sulcus is a groove that a. Separates the atrioventricular valves from the atria. b. Marks the boundary line between the right and left ventricles. c. Marks the boundary line between the right and left atria. d. Separates the coronary arteries from the coronary veins. e. Marks the border between the atria and ventricles.

48) The pectinate muscles are a. anchor the chordae tendinae. b. support the atrioventricular valves. c. close the semilunar valves. d. ridges in the walls of the ventricles. e. ridges that run along the surface of the auricles.

49) The cusps of atrioventricular valves are attached to papillary muscles by the a. Trabeculae carneae. b. Coronary sulci. c. Pectinate muscles. d. Chordae tendineae. e. Interatrial septa.

50) Contractions of the papillary muscles a. Close the semilunar valves. b. Eject blood from the ventricles. c. Eject blood from the atria into the ventricles. d. Close the atrioventricular valves. e. Prevent the atrioventricular valves from reversing into the atria.

51) The visceral pericardium is the same as the a. Myocardium. b. Endocardium. c. Mediastinum. d. Parietal pericardium. e. Epicardium.

52) A function of the pericardium includes a. Preventing expansion of the heart. b. Anchoring the heart to surrounding structures. c. Pumping blood into circulation. d. Removing excess fluid from the heart chambers. e. both A and D

53) The right ventricle pumps blood to the a. Left ventricle. b. Left atrium. c. Systemic circuit. d. Lungs. e. Right atrium.

54) The left ventricle pumps blood to the a. Right atrium. b. Lungs. c. Right ventricle. d. Systemic circuit. e. Pulmonary circuit.

55) The right atrium receives blood from the a. Inferior vena cava. b. Conus arteriosus. c. Pulmonary veins. d. Aorta. e. Pulmonary trunk.

56) The AV valve on the side of the heart that receives the superior vena cava is the a. tricuspid valve. b. pulmonary semilunar valve. c. bicuspid valve. d. aortic semilunar valve. e. mitral valve.

57) Blood leaving the right ventricle enters the a. Aorta. b. Pulmonary trunk. c. Pulmonary veins. d. Superior vena cava. e. Inferior vena cava.

58) The pulmonary semilunar valve guards the entrance to the a. Pulmonary trunk. b. Right ventricle. c. Left ventricle. d. Aorta. e. Pulmonary veins.

59) The bicuspid or mitral valve is located a. In the opening of the aorta. b. Between the right atrium and right ventricle. c. Between the left atrium and left ventricle. d. In the opening of the pulmonary trunk. e. Where the vena cavae join the right atrium.

60) The entrance to the ascending aorta is guarded by the ________ valve. a. bicuspid b. tricuspid c. semilunar d. atrioventricular e. mitral

61) The function of an atrium is to a. Pump blood into the systemic circuit. b. Pump blood to the lungs. c. Pump blood to the heart muscle. d. Collect (receive) blood. e. both A and D

62) Compared to the right ventricle, the left ventricle has all the following except that it a. Has a thicker wall. b. Produces 4-6 times more force when it contracts. c. Is round in cross section. d. Relaxes more slowly. e. Develops higher pressures when it contracts.

63) The following is a list of vessels and structures that are associated with the heart. 1. right atrium 2. left atrium 3. right ventricle 4. left ventricle 5. vena cavae 6. aorta 7. pulmonary trunk 8. pulmonary veins What is the correct order for the flow of blood entering from the systemic circulation? a. 1, 7, 3, 8, 2, 4, 6, 5 b. 1, 2, 7, 8, 3, 4, 6, 5 c. 5, 1, 3, 8, 7, 2, 4, 6 d. 5, 3, 1, 7, 8, 4, 2, 6 e. 5, 1, 3, 7, 8, 2, 4, 6

64) The left and right pulmonary arteries carry blood to the a. Heart. b. Brain. c. Lungs. d. Liver. e. Intestines.

65) The myocardium is primarily composed of ________ tissue. a. cardiac muscle b. elastic c. epithelial d. fibrous connective e. smooth muscle

66) The first blood vessels to branch from the aorta are the ________ arteries. a. coronary b. circumflex c. subclavian d. pulmonary e. carotid

67) The marginal branch and posterior interventricular branch are branches of the a. Right coronary artery. b. Coronary sinus. c. Left coronary artery. d. Aorta. e. Circumflex artery.

68) The circumflex branch and the anterior descending artery are branches of the a. Interventricular artery. b. Right coronary artery. c. Aorta. d. Coronary sinus. e. Left coronary artery.

69) The great and middle cardiac veins drain blood into the a. Aorta. b. Inferior vena cava. c. Superior vena cava. d. Coronary sulcus. e. Coronary sinus.

70) The heart is innervated by ________ nerves. a. parasympathetic . b. sympathetic. c. Both parasympathetic and sympathetic. d. neither parasympathetic nor sympathetic.

71) In cardiac muscle, the depolarization phase of the action potential is the result of a. Increased membrane permeability to chloride ions. b. Decreased membrane permeability to calcium ions. c. Decreased membrane permeability to sodium ions. d. Increased membrane permeability to sodium ions. e. Increased membrane permeability to potassium ions.

72) The plateau phase of the cardiac muscle action potential is due to a. The increased membrane permeability to potassium ion. b. The calcium channels remaining open longer than the sodium channels. c. Increased membrane permeability to sodium ions. d. The movement of fewer sodium ions across the cell membrane. e. A decrease in the amount of calcium diffusing across the membrane.

73) In cardiac muscle a. Calcium ions do not bind to troponin molecules. b. Calcium ions play no role in the process of contraction. c. Some of the calcium ion required for contraction comes from outside the cell. d. Calcium ions are not released from the sarcoplasmic reticulum. e. Calcium ions play an important role in repolarizing the membrane after the depolarization phase.

74) The pacemaker cells of the heart are located in the a. SA node. b. Wall of the left ventricle. c. AV node. d. Both the left and right ventricles. e. Purkinje fibers.

75) The following are components of the conducting system of the heart. 1. Purkinje fibers 2. AV bundle 3. AV node 4. SA node 5. bundle branches The sequence in which an action potential would move through this system is a. 3, 2, 4, 5, 1. b. 4, 3, 2, 5, 1. c. 3, 5, 4, 2, 1. d. 4, 2, 3, 5, 1. e. 1, 4, 3, 2, 5.

76) Depolarization of the ventricles is represented on an EKG by the a. PR complex. b. P wave. c. QRS complex. d. S wave. e. T wave.

77) The T wave on an EKG represents a. Atrial depolarization. b. Ventricular contraction. c. Ventricular depolarization. d. Atrial repolarization. e. Ventricular repolarization.

78) Analysis of the EKG can reveal all of the following, except the a. Size of the ventricles. b. Effects of altered ion concentrations. c. Condition of the pulmonary trunk. d. Condition of the conducting system. e. Position of the heart in the thoracic cavity.

79) The first heart sound is heard when the a. Blood enters the aorta. b. AV valves close. c. AV valves open. d. Semilunar valves close. e. Atria contract.

80) During the isovolumetric phase of ventricular systole, the a. Atrioventricular valves and semilunar valves are closed. b. Atria are contracting and the ventricles are relaxing. c. Blood is ejected into the great vessels. d. all of the above e. B and C only

81) During the cardiac cycle, the a. Second heart sound coincides with the QRS complex of the ECG. b. Third heart sound occurs during atrial systole. c. P wave of the ECG occurs between the first and second heart sounds. d. QRS complex of the ECG precedes the increase in ventricular pressure. e. both A and C

82) The volume of blood ejected from each ventricle during a contraction is called the a. Stroke volume. b. Cardiac output. c. Cardiac reserve. d. End-diastolic volume. e. End-systolic volume.

83) Each of the following factors will increase cardiac output, except a. Increased parasympathetic stimulation. b. Increased heart rate. c. Increased venous return. d. Increased sympathetic stimulation. e. both B and D.

84) According to Starling's "law of the heart," the cardiac output is directly related to the a. Heart rate. b. Size of the ventricle. c. Venous return. d. End-systolic volume. e. Thickness of the myocardium

85) Each of the following conditions would increase heart rate, except a. Increased sympathetic stimulation of nodal fibers. b. Increased parasympathetic stimulation of nodal fibers. c. Increased levels of epinephrine in the interstitial fluid surrounding the myocardium. d. Activation of cAMP in heart muscle. e. Increased permeability of the myocardial membrane to sodium ion.

86) Increased venous blood flow to the right atrium a. Causes cells of the SA node to depolarize faster. b. Triggers the atrial (Bainbridge) reflex. c. Will result in increased heart rate. d. B and C only, e. all of the above,

87) Drugs known as beta-blockers will a. Decrease the end-systolic volume. b. Increase heart rate. c. Increase stroke volume. d. Decrease heart rate. e. Increase cardiac output.

88) The heart beats approximately ________ times each day. a. 1,000 b. 10,000 c. 100,000 d. 1,000,000 e. 1,000,000,000

89) The heart pumps approximately ________ liters of blood each day. a. 8,000 b. 15,000 c. 20,000 d. 50,000 e. 100,000

90) The heart is roughly the size of ________. a. A man's clenched fist. b. The gallbladder. c. The hand of a 10-year-old. d. A thigh. e. none of the above

91) If you were to dissect a cadaver and cut a midsagittal section through the trunk, it would not divide the heart into equal halves because a. The entire heart is rotated to the left around the center line. b. A line drawn between the center of the base and the apex points farther to the left. c. The center of the base lies slightly to the left of the midline. d. all of the above. e. none of the above.

92) The pericardial fluid is important because it a. Acts as a cushion. b. Acts as a lubricant. c. Reduces friction. d. all of the above. e. none of the above

93) The term used to describe fluid collecting in the pericardial cavity that restricts the beating of the heart is known as a. Mitral valve prolapses. b. cardiac tamponade. c. pleurale effusion. d. Cardiomyopathy. e. Pericarditis.

94) The connective tissue of the epicardium at the interventricular and coronary sulci generally contains a. Arteries. b. Fat. c. Veins. d. both B and C. e. all of the above.

95) Intercalated discs convey the force of contraction from cell to cell and propagate a. Abnormal EKG rhythm. b. Action potentials. c. The tendency for late decelerations. d. both A and C. e. both A and B.

96) The atrioventricular valves permit blood flow a. In any direction. b. In one direction only. c. In several directions. d. both A and C. e. none of the above.

97) Cardiac muscle cells are a. Anaerobic. b. Non-oxygen needing. c. Aerobic. d. both A and B. e. both A and C.

98) The coronary sinus opens into the a. Left atrium. b. Right ventricle. c. Right atrium. d. Left ventricle. e. Pulmonary trunk.

99) There are ________ pulmonary veins. a. 2 b. 4 c. 6 d. 8 e. none of the above

100) Damage to the chordae tendinae in the left ventricle may result in a. Mitral valve prolapses. b. Mitral regurgitation. c. Bicuspid prolapse. d. Bicuspid regurgitation. e. all of the above.

101) When the semilunar valves close, the AV valves ________. a. Open. b. make a distinct heart sound. c. Close. d. none of the above. e. both A and B.

102) The ________ ventricle has a greater workload than the ________. a. right; systemic circulation. b. left; right ventricle. c. right; left ventricle. d. both A and C. e. none of the above.

103) The connective-tissue fibers a. Provide elasticity to help return the heart to its normal size. b. Add strength and prevent overexpansion of the heart. c. Help distribute the forces of contraction. d. Provide physical support for cardiac muscle. e. all of the above.

104) Blood is supplied to the left atrium via the a. Pulmonary arteries. b. Left coronary artery. c. Pulmonary veins. d. Superior vena cava. e. Right coronary artery.

105) One of the first symptoms of coronary artery disease is a. Angina. b. Chest pain. c. Increased pulse. d. Difficulty breathing. e. both A and B.

106) Most of the cells of the conducting system are ________ than the contractile cells of the myocardium and contain ________ myofibrils. a. larger; few b. smaller; many c. larger; several d. smaller; few e. none of the above

107) If an action potential is initiated in the AV node, you would expect the heartbeat to be ________beats per minute. a. 20-40 b. 40-60 c. 60-100 d. 100-140 e. 140-180

108) ________ is to slow heart rate as ________ is to fast heart rate. a. Bradycardia; cardiomyopathy b. Cardiac tamponade; bradycardia c. Bradycardia; tachycardia d. Tachycardia; bradycardia e. none of the above

109) ________ is to contraction as ________ is to relaxation. a. Systole; diastole b. Diastole; systole c. Filling; relaxing d. Systole; filling e. both A and D.

110) The structure that permits blood flow from the right atrium to the left atrium while the lungs are developing before birth is the a. Interatrial septum. b. Ligamentum arteriosis. c. Foramen ovale. d. Coronary sinus. e. Fossa ovalis.

111) Blood leaves the right ventricle by passing through the a. Pulmonary valve. b. Mitral valve. c. Bicuspid valve. d. Aortic valve. e. Tricuspid valve.

112) Tetanic muscle contractions cannot occur in a normal cardiac muscle cell because a. Cardiac muscle tissue contracts on its own. b. The refractory period lasts until the muscle cell relaxes. c. The refractory period ends before the muscle cell reaches peak tension. d. There is no neural or hormonal stimulation. e. none of the above

113) The amount of blood that is forced out of the heart depends on a. The amount of pressure required to eject blood. b. The degree of stretching at the end of ventricular diastole. c. The contractility of the ventricle. d. A and B only e. All of the above

114) Cardiac muscle is similar to skeletal muscle in the a. Presence of intercalated discs. b. Arrangement of the T-tubules. c. Presence of striations. d. Arrangement of the sarcoplasmic reticulum. e. both A and D.

115) At an intercalated disc a. The myofibrils are loosely attached to the membrane of the disc. b. The cell membranes of two cardiac muscle fibers are completely separated by a synapse. c. T-tubules unite the membranes of the adjoining cells. d. Two cardiac muscle cells are connected by a gap junction. e. both B and C

116) During ventricular systole, the a. Atria are contracting. b. AV valves are closed. c. Blood is entering the ventricles. d. Pressure in the ventricles declines. e. Ventricles are relaxed.

117) When the left ventricle contracts, the distance from the apex to the base a. Remains unchanged. b. Decreases. c. Increases.

118) When the left ventricle contracts, the diameter of the ventricular chamber a. Decreases. b. Remains the same. c. Increases.

119) As a result of the long refractory period, cardiac muscle cannot exhibit a. Treppe. b. Recruitment. c. Tonus. d. Tetany. e. Fatigue.

120) Which of the following is greater? a. the concentration of calcium ions in the sarcoplasmic reticulum of skeletal muscle b. the concentration of calcium ions in the sarcoplasmic reticulum of cardiac muscle

121) Drugs known as calcium channel blockers can be used to a. Increase blood pressure. b. Increase stroke volume. c. Increase sympathetic stimulation of the myocardium. d. Decrease the force of cardiac contraction. e. Constrict the coronary arteries.

122) Enzymes that are found in blood following a myocardial infarction include all of the following, except a. ST-P. b. CPK. c. MB-CK. d. SGOT. E e. LDH.

123) When a clot forms on the plaque in a coronary vessel and obstructs blood flow to the muscle, the condition is referred to as a(n) a. Coronary thrombosis. b. Angioplasty. c. Pulmonary embolism. d. Myocardial infarction. e. Angina pectoris.

124) Which of the following is greater? a. the number of action potentials per minute spontaneously generated by the SA node b. the number of action potentials per minute spontaneously generated by the AV node c. Neither is greater.

125) Which of the following is greater? a. the conduction velocity along a Purkinje fiber b. the conduction velocity along a normal myocardial fiber c. Neither is greater.

126) Which of the following is greater during left ventricular systole? a. the pressure in the ventricle b. the pressure in the aorta c. Neither is greater.

127) If the connections between the vagus nerve and the heart are severed, the a. Heart will beat slower. b. Cardiac output will decrease. c. Stroke volume will decrease. d. Nodal fibers will depolarize more slowly. e. Heart will beat faster.

128) Which of the following would be greater? a. the amount of intracellular calcium ions in cardiac muscle after beta receptors are stimulated b. the amount of intracellular calcium ions in cardiac muscle after muscarinic receptors are stimulated

129) Cardiac output would be greatest when a. Parasympathetic stimulation of the heart increases. b. Sympathetic stimulation of the heart increases.

130) Which of the following would be greater? a. the end-diastolic volume when the heart rate is 90 beats/minute b. the end-diastolic volume when the heart rate is 150 beats/minute

131) Which of the following would be greater? a. stroke volume when extracellular calcium ion concentrations are low b. stroke volume when extracellular calcium ion concentrations are high

132) Which of the following is greater? a. heart rate when acetylcholine is released at the SA node b. heart rate when norepinephrine is released at the SA node

133) Abnormally slow conduction through the ventricles would change the shape of a. R-T interval b. T wave c. QRS complex d. P-R interval e. P wave

134) The ECG of a person suffering from third-degree heart block would show a. No association between P wave and QRS complex. b. A smaller QRS complex. c. No visible T wave. d. More P waves than QRS complexes per minute. e. An inverted P wave.

135) If the membrane of the cardiac muscle cells in the SA node become more permeable to potassium ions, the a. Stroke volume will increase. b. Intracellular concentration of calcium ion will increase. c. Membrane will depolarize. d. Heart rate will increase. e. Heart rate will decrease.

136) If the connection between the SA node and AV node becomes blocked, a. The ventricular rate of contraction will not be affected. b. The ventricles will beat more slowly. c. The ventricles will beat faster. d. The stroke volume will increase. e. none of the above

137) If a myocardial infarction results in the formation of scar tissue along the pathway of the left bundle branch, a. Cardiac arrhythmias may occur. b. Conduction through the left ventricle would remain normal. c. Blood flow to the lungs will decrease. d. The right ventricle will fail to contract. e. The ventricle will contract more forcefully.

138) What effect would compressing the inferior vena cava just below the diaphragm have on cardiac function? a. Stroke volume would increase. b. Sympathetic stimulation of the heart would increase. c. Cardiac output would increase. d. all of the above e. both A and B

139) In which situation would the end-systolic volume (ESV) be the greatest? a. when parasympathetic stimulation of the heart is increased b. when stroke volume is increased c. when the force of myocardial contraction is increased d. when sympathetic stimulation of the heart is increased e. when the intracellular stores of calcium are increased

140) In which situation would the stroke volume be the greatest? a. when the force of contraction is decreased b. when calcium channel blockers are present c. when the difference between the end-diastolic volume and the end-systolic volume is small d. when venous return is increased e. when venous return is decreased

141) Manganese ion blocks the calcium channels in the cardiac muscle membrane. How would the presence of manganese in the extracellular fluid affect the contraction of the heart muscle? a. The heart rate would increase. b. The heart would beat less forcefully. c. The refractory period would be shorter. d. The plateau phase of contraction would be shorter. e. The contraction phase would be prolonged.

142) David suffers from a regurgitating mitral valve. This condition would cause a. Fluid congestion in the lungs. b. Increased cardiac output from the right ventricle. c. Decreased force of cardiac contraction. d. Decreased heart rate. e. Increased cardiac output from the left ventricle.

1) If there is a blockage between the AV node and the AV bundle, how will this affect the appearance of the electrocardiogram? a. The P-R interval will be smaller. b. There will be more P waves than QRS complexes. c. The QRS interval will be longer. d. There will be more QRS complexes than P waves. e. The T wave will disappear.

144) The left border of the heart is formed by the ________. a. Left ventricle and a small portion of the left atrium b. Right ventricle and a small portion of the right atrium c. Left ventricle only d. Right ventricle only e. Left and right ventricles

145) The wall of the ________ forms most of the inferior border of the heart. a. Right ventricle b. Left ventricle c. Right atrium d. Left atrium.

146) The _____ surface of the heart primarily consists of the right atrium and right ventricle. a. Anterior or sternocostal b. Posterior c. Lateral d. medial

147) Deep grooves and folds on the inner surface of the ventricles are called ________. a. Trabeculae carneae b. Pictinate muscle c. Auricle d. Non of the above

148) The ________ lines the chambers of the heart and the heart valves, and is continuous with the lining of the attached blood vessels. a. Endocardium b. Pericardium c. myocardium

149) ________ are abnormal heart sounds. a. Murmurs b. Regurgitation c. Arrhythmia d. Irregular e. Dysrythmia

150) The backflow of blood from one chamber to another or from one of the large vessels to the ventricle is called ________. a. Regurgitation b. Prolapse c. Murmur d. Arrhythmia

151) The ________ is the amount of blood in a ventricle at the beginning of systole. a. End-diastolic volume b. End-systolic volume c. Cardiac output d. Stork volume

152) The ________ is the amount of blood in a ventricle after it has contracted and before it begins to refill. a. End-diastolic volume b. End-systolic volume c. Cardiac output d. Stork volume

153) In a procedure known as ________, an inflatable balloon at the end of a catheter is used to remove plaque from blood vessels. a. Balloon angioplasty b. Coronary bypass surgery c. Catheter

154) A procedure in which a small section of a peripheral vein is used to create a detour around an obstruction in a coronary artery is called ________. a. Balloon angioplasty b. Coronary bypass surgery c. Catheter

155) A (n) ________ is a small-diameter tube that can be used to remove plaque from the walls of a blood vessel. a. Balloon angioplasty b. Coronary bypass surgery c. Catheter

156) As the left ventricle contracts, it bulges into the ________. a. Right ventriclular cavity b. Right atrial cavity c. Left atrial cavity

157) The pulmonary trunk is attached to the aortic arch by the ________. a. Ligamentum arteriosum b. Ligamentum venosum c. Ligamentum ligamentosum