BIOL 4350 Cardiovascular Physiology Dr. Hamilton. Using the figure above, match the following: 1. Purkinje fibers. 2. SA node. 3. AV node.

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BIOL 4350 Cardiovascular Physiology Dr. Hamilton Using the figure above, match the following: 1. Purkinje fibers. 2. SA node. 3. AV node. 1

Using the figure above, match the following: 4. Atrial depolarization. 5. Point after which pressure begins to rise in the aorta. 6. Point of the least ventricular volume. 7. Point that represents the "dup" sound made by the heart. Matching 8. The lining of the heart. 9. Heart muscle. 10. Serous layer covering the heart muscle. A. Myocardium B. Epicardium C. Endocardium Matching 11. The pacemaker of the heart. 12. Found in the interventricular septum. 13. Network found in the ventricular myocardium. 14. The point in the conduction system of the heart where the impulse is temporarily delayed. A. AV bundle B. Purkinje fibers C. AV node D. SA node 2

Matching 15. Prevents backflow into the left ventricle. 16. Prevents backflow into the right atrium. 17. Prevents backflow into the left atrium. 18. Prevents backflow into the ventricles. 19. AV valve with two flaps. 20. AV valve with three flaps. A. Aortic semilunar valve B. Tricuspid valve C. Pulmonary semilunar valves D. Mitral valve True or False: If false, correct the statement in the space provided. 21. The myocardium receives its blood supply from the coronary arteries. 22. Cardiac muscle has more mitochondria and depends less on a continual supply of oxygen than does skeletal muscle. 23. Tissues damaged by myocardial infarction are replaced by connective tissue. 24. The left side of the heart pumps the same volume of blood as the right. 25. The mitral valve has chordae but the tricuspid valve does not. 26. The "lub" sounds of the heart are valuable in diagnosis because they provide information about the function of the heart's semilunar valves. 27. Autonomic regulation of heart rate is via two reflex centers found in the pons. 28. An ECG provides direct information about valve function. Multiple Choice 29. Normal heart sounds are caused by which of the following events? A. friction of blood against the chamber walls B. closure of the heart valves C. contraction of ventricular muscle D. excitation of the SA node 30. Hemorrhage with a large loss of blood causes: A. no change in blood pressure but a slower heart rate. B. a rise in blood pressure due to change in cardiac output. C. a lowering of blood pressure due to change in cardiac output. D. no change in blood pressure but a change in respiration. 31. The left ventricular wall of the heart is thicker than the right wall in order to: A. pump blood with greater pressure B. expand the thoracic cage during diastole. C. pump blood through a smaller valve D. accommodate a greater volume of blood. 3

32. Damage to the is referred to as heart block. A. AV bundle B. SA node C. AV valves D. AV node 33. The P wave of a normal electrocardiogram indicates: A. atrial depolarization B. ventricular depolarization C. atrial repolarization D. ventricular repolarization. 34. Blood within the pulmonary veins returns to the: A. right atrium B. left ventricle C. right ventricle. D. left atrium. 35. Small muscle masses attached to the chordae tendineae are the: A. venae cavae B. papillary muscles C. pectinate muscles D. trabeculae carneae. 36. Blood is carried to capillaries in the myocardium by way of: A. coronary veins B. the coronary sinus C. coronary arteries D. the fossa ovalis. 37. When the heart is beating at a rate of 75 times per minute, the duration of one cardiac cycle is second(s). A. 1.2 B. 0.8 C. 1.0 D. 1.8 38. Which of the following factors does not influence heart rate? A. gender B. body temperature C. skin color D. age 39. If cardiac muscle is deprived of its normal blood supply, damage would primarily result from: A. decreased delivery of oxygen. B. a lack of nutrients to feed into metabolic pathways. C. an inadequate supply of lactic acid. D. a decrease in the number of available mitochondria for energy production. 40. Cardiac output is about L/min. A. 6.26 B. 5.25 C. 7.27 D. 4.25 41. The pericardial cavity: A. is a space between the fibrous pericardium and the serous pericardium. B. contains a lubricating fluid called serous fluid. C. is the region of the thoracic cavity that contains the heart. D. is another name for the chambers of the heart. 4

42. If the vagal nerves to the heart were cut, the result would be that: A. the AV node would become the pacemaker of the heart. B. the heart would stop, since the vagal nerves trigger the heart to contract. C. parasympathetic stimulation would increase, causing a decrease in heart rate. D. the heart rate would increase by about 25 beats per minute. 43. Foramen ovale: A. connects the two atria in the fetal heart. B. is a connection between the pulmonary trunk and the aorta in the fetus. C. is a shallow depression in the interventricular septum. D. is a condition in which the heart valves do not completely close. 44. The stroke volume for a normal resting heart is ml/beat. A. 70 B. 50 C. 90 D. 30 45. Which vessel of the heart receives blood during right ventricular systole? A. pulmonary veins B. pulmonary artery C. venae cavae D. aorta 46. Blood enters which of these vessels during ventricular systole? A. pulmonary vein B. pulmonary arteries C. aorta D. aorta and pulmonary arteries 47. Which of the following is not part of the conduction system of the heart? A. AV node B. bundle of His C. SA node D. AV valve 48. The tricuspid valve is closed: A. while the atrium is contracting. B. when the ventricle is in systole. C. while the ventricle is in diastole. D. by the movement of blood from atrium to ventricle. 49. Select the correct statement about the heart valves. A. Semilunar valves control the flow of blood into the heart. B. The AV valves are supported by chordae tendineae so that they do not blow back up into the atria during ventricular contraction. C. The tricuspid valve divides the left atrium from the left ventricle. D. The mitral valve separates the right atrium from the right ventricle. 50. Select the correct statement about the structure of the heart wall. A. The fibrous skeleton forms the bulk of the heart. B. The myocardium is the layer of the heart that actually contracts. C. The heart chambers are lined by the endomysium. D. Connective tissue in the heart wall aids in the conduction of the action potential. 5

51. Compared to skeletal muscle, cardiac muscle: A. lacks striations. B. has gap junctions that allow it to act as a functional syncytium. C. has more nuclei per cell. D. cells are larger than skeletal muscle cells. 52. The deflection waves in an ECG tracing include: A. the PQRS complex, which follows ventricular contraction. B. the T wave, which indicates ventricular repolarization. C. the Q-T interval, which indicates the time of atrial contraction. D. the P wave, which is present only in patients who have had a heart attack. 53. During the period of ventricular filling: A. blood flows into the ventricles from the atria through the open AV valves. B. pressure in the heart is at its peak. C. it is represented by the QRS complex on the ECG. D. the atria remain in diastole. 54. The effect of endurance-type athletic training may be to lower the resting heart rate. This phenomenon: A. does not occur in aerobic training B. is caused by hypertrophy of the heart muscle. C. is a sign of dangerous overexertion D. results in decreased cardiac output. Fill-in-the-Blank 55. In the fetal heart there is a foramen that allows blood to flow from the right atrium directly to the left atrium. 56. Specialized conductive cells of the ventricles are called fibers. 57. The ECG T wave interval represents. 58. CO = x SV. 59. The is a membrane that covers the heart. 60. The valve of the heart has three cusps with chordae tendineae. 61. valves of the heart have no chordae tendineae attached. Short Answer 62. Define systole and diastole. Which heart chambers are usually referenced when these terms are used? 63. What is the difference between the auricles and the atrium? 6

64. The heart is called a "double pump" because there are two functionally separate circulations. Trace the pathway of each of these circulations and include the following information: heart chambers involved, major blood vessels involved, and general areas through which the blood flows. Begin with the right atrium. 65. What two important functions does the cardiac conduction system perform? 66. Explain autorhythmicity in cardiac muscle cells. 67. Why is oxygen so much more critical to the heart muscle than to skeletal muscles? 68. What is the functional importance of the intercalated discs of cardiac muscle? What is the functional importance of the fibrous skeleton of the heart? Multiple Choice 69. A healthy adult male individual contains about liters of blood. a. 7-8 b. 5-6 c. 3-4 d. 2-3 e. 1-2 70. A major plasma protein that maintains the blood osmotic pressure is a. Angiotensinogen b. Fibrinogen c. Albumin d. Globulin e. Fibrin 71. Blood group O a. does not have the anti-a and anti-b antibodies in the serum. b. can receive blood from either group A or B but not from group AB. c. has the AB antigens on its plasma membrane. d. is a universal donor because they can give blood to all other groups. e. is a universal recipient because they can receive blood from all other groups. 72. Diapedisis refers to a. the type of movement erythrocytes use in the tissue spaces. b. the secretion of chemicals that trigger the inflammatory process. c. the chemical attraction leukocytes use to reach the site of tissue damage. d. the escape of leukocytes from blood vessels into tissue spaces. e. the engulfing of foreign bodies by leukocytes. 7

73. Mature red blood cells in the circulating blood are filled with a. Nuclei and all other cellular organelles b. Hemoglobin molecules c. Smooth endoplasmic reticulum d. Mitochondria e. Lysosomes 74. The final step in clot formation is a. The release of chemical by platelets b. Platelet plug formation c. Formation of prothrombin activator d. Prothrombin --> Thrombin e. Fibrinogen --> Fibrin 75. When red blood cells transport respiratory gases a. oxygen binds to the heme portion while carbon dioxide binds to the globin portion. b. both oxygen and carbon dioxide combine to the heme portion. c. both oxygen and carbon dioxide combine to the globin portion. d. the main form of gas transport in the body is through the plasma. e. carbon dioxide binds to the heme portion and oxygen binds to the globin portion. Matching 76. Have both anti-a and anti-b antibodies 77. Have both antigens A and B 78. Have only anti-a antibody 79. Have the antigen A A. Blood group AB B. Blood group A C. Blood group B D. Blood group O Matching 80. Water 81. Albumin 82. Globulins 83. Non-protein nitrogenous substances 84. Electrolytes A. Produced by liver; exerts osmotic pressure to maintain water balance between blood and tissues B. By-products of cellular metabolism (urea, uric acid) C. Involved in transport of lipids; involved in immune response D. Sodium, calcium, potassium, chloride, phosphate, sulfate E. 90% of plasma volume; dissolving and suspending medium for solutes of blood 8

True or False: If false, correct the statement in the space provided 85. Each hemoglobin molecule has four polypeptide chains- two alpha and two beta chains. 86. Hemoglobin serves to transport oxygen, but not carbon dioxide. 87. Plasma contains water, proteins, nutrient molecules and hormones. 88. The demand for more oxygen by the body tissues increases as a person moves to higher altitudes. 89. When oxygen is bound to hemoglobin it becomes oxyhemoglobin. 90. The most abundant organic component of plasma is protein. 91. Formed elements of blood include erythrocytes, leukocytes and platelets. 92. Hemoglobin is the protein that makes red blood cells red. Multiple Choice 93. During pulmonary circulation blood leaves the a. left ventricle and moves to the lungs. b. right atrium and goes directly to the lungs. c. right ventricle and goes directly to the aorta. d. right atrium and goes directly to the left ventricle e. right ventricle and moves to the lungs. 94. During systemic circulation, blood leaves the a. right ventricle and moves to the lungs. b. right ventricle and goes directly to the aorta. c. lungs and moves to the left atrium. d. right atrium and goes directly to the lungs. e. left ventricle and goes directly to the aorta. 95. The inferior vena cava brings blood from the lower regions of the body and empties into the a. left atrium. b. left ventricle. c. right ventricle. d. aorta. e. right atrium. 9

96. Which of the following is the major force generating blood flow? a. Pumping action of the heart b. Peripheral resistance c. Blood vessel diameter d. Blood viscosity e. Total blood vessel length 97. The major long-term mechanism of blood pressure control is provided by the a. The heart b. The digestive tract c. Kidneys d. Paravertebral ganglia e. The lungs 98. Blood enters the myocardium of the heart by cornary vessels that originate from the a. the pulmonary artery. b. Aorta. c. the superior vena cava. d. the inside of the ventricles. e. the pulmonary veins. 99. Exchange of gases and nutrients occurs by diffusion between the a. Arterioles and tissue cells b. Arterioles and venules c. Arteries and veins d. Artery walls and tissue cells e. Capillaries and tissue cells 100. Reduction in lumen diameter of a blood vessel as the smooth muscle contracts is known as a. Atherosclerosis b. Arteriosclerosis c. Varicose veins d. Vasodilation e. Vasoconstriction 101. The only vessels that provide direct access to nearly every cell in the body are the a. Arteries b. Arterioles c. Capillaries d. Veins e. Venules 10

Matching 102. Brings oxygen-rich blood from the lungs to the L. Atrium 103. The right ventricle sends blood into this vessel 104. Brings oxygen-poor blood from the lower body to right atrium 105. Brings oxygen-poor blood from the upper body to right atrium 106. The left ventricle sends blood into this vessel A. Pulmonary trunk B. Superior vena cava C. Aorta D. Pulmonary veins E. Inferior vena cava True or False: If false, correct the statement in the space provided 107. Blood pressure in capillaries is lower than in arterioles. Multiple Choice 108. Cardiac Output is a. The number of times the heartbeats in one minute b. The number of impulses fired by the SA node in one minute c. The amount of blood filling each ventricle at the end of diastole d. The amount of blood pumped out of each ventricle in one minute e. The amount of blood pumped out of the heart during every ventricular contraction 109. Choose the correct sequence of current flow through the heart wall. a. AV node, Purkinje fibers, AV node, AV bundle of His, right and left bundle branches b. SA node, AV node, AV bundle of His, right and left bundle branches, Purkinje fibers c. SA node, Purkinje fibers, AV node, AV bundle of His, right and left bundle branches d. AV node, SA node, Purkinje fibers, AV bundle of His, right and left bundle branches e. Purkinje fibers, AV node, AV bundle of His, right and left bundle branches, SA node 110. Identify the correct sequence of blood flow through the chambers of the heart. a. Left atrium left ventricle, right ventricle, right atrium, and lungs b. Right ventricle, left ventricle, left atrium, lungs, right atrium c. Left ventricle, left atrium, lungs, right ventricle, right atrium d. Lungs, right ventricle, left ventricle, right atrium, left atrium e. Right atrium, right ventricle, lungs, left atrium, left ventricle 111. The cardiac cycle includes all of the following events except a. the changes in pressure gradients in all chambers of the heart. b. the closing and opening of the heart valves during each heart beat. c. the changes in blood volume in all chambers of the heart. d. the number of times the heart beats in one minute. e. the movement of impulse from the SA node to all regions of the heart wall. 11

112. The P-wave is a measure of a. ventricular contraction. b. atrial depolarization. c. atrial repolarization. d. ventricular depolarization. e. ventricular hyperpolarization. 113. The pacemaker of the heart is the a. AV node b. Bundle of His c. SA node d. The bundle branches e. Perkinje fibers 114. The tricuspid valves are located between the a. right atrium and right ventricle. b. right and left atria. c. left atrium and left ventricle. d. right ventricle and the aorta. e. right and left ventricles. 115. When the bicuspid valve closes, it prevents the back-flow of blood from the a. right ventricle into the pulmonary trunk. b. left atrium into the left ventricle. c. left ventricle into the left atrium. d. left ventricle into the aorta. e. right atrium into the right ventricle. 116. Which statement about the extrinsic innervation of the heart is NOT true? a. The vagus nerve is the tenth cranial nerve. b. Sympathetic impulses travel through the vagus nerve. c. Sympathetic nerve stimulation of the heart increases the rate and force of the heart. d. parasympathetic nerve stimulation reduces the heartbeat e. The cardiac centers are located in the medulla oblongata of the brain stem. True or False: If false, correct the statement in the space provided. 117. An EKG measures the contraction of the atria and the ventricles. 118. Both gap junctions and desmosomes are found within intercalated discs. 119. The AV node is the pacemaker of the heart. 120. The contraction of the ventricles precedes the QRS complex. 121. The first heart sound is produced by the closure of the atrioventricular valves. 12

122. The myocardium is the thickest layer in the wall of the heart. 123. The superior vena cava, inferior vena cava, and the coronary sinus empty into the left atrium. 124. The "discharging" chambers of the heart are the ventricles. 125. The blood vessels that carry blood to and from the body tissues form the pulmonary circuit. 126. The aortic and pulmonary semilunar valves prevent backflow of blood into the associated ventricles. 127. Cardiac output (CO) is the amount of blood pumped out by each ventricle each time the heart beats. 128. When the ventricles are in systole, the atria are in diastole. 13

Answer Key 1. e 2. a 3. b 4. a 5. d 6. e 7. e 8. c 9. a 10. b 11. d 12. a 13. b 14. c 15. a 16. b 17. d 18. c 19. d 20. b 21. True 22. False, cardiac muscle depends more on oxygen supply than skeletal muscle 23. True 24. True 25. False, both AV valves have chordae tendineae 26. False, diagnoistic of AV valves 27. False, medulla 28. False, ECG provides information about conduction system 29. b 30. c 31. a 32. d 33. a 34. d 35. b 36. c 37. b 38. c 39. a 40. b 41. b 42. d 43. a 44. a 45. b 46. d 47. d 48. b 49. b 50. b 51. b 52. b 53. a 54. b 55. ovale 56. Purkinje 57. ventricular repolarization 58. HR or heart rate 59. parietal pericardium 60. tricuspid 61. Semilunar 62. Systole is contraction of the muscle. Diastole is relaxation of the muscle. The contraction and relaxation of the ventricles are normally described with the terms systole and diastole. 63. Auricles are the flap-like appendages attached to the atria that increase the atrial volume. 64. Right atrium to right ventricle to pulmonary arteries to lungs (pulmonary circuit pump.; pulmonary veins to left atrium to left ventricle to aorta to body tissues to venae cavae (systemic circuit pump.. 65. The important functions of the cardiac conduction system are to initiate impulses (pacemaker. and to distribute impulses throughout the heart so that it depolarizes and contracts in an orderly, sequential manner. 66. Autorhythmic cells do not maintain a stable resting membrane potential. 14

Instead, they have an unstable resting potential that continuously depolarizes, drifting toward threshold for firing. 67. Skeletal muscles can go into oxygen debt by burning sugars anaerobically; the heart cannot do this. Since there is no stored oxygen in the cardiac cells, any occlusion to the heart is extremely serious. 68. Intercalated disks contain anchoring desmosomes that prevent cell separation, and gap junctions that allow ions to travel from cell to cell. The fibrous skeleton is connective tissue that reinforces the myocardium internally. 69. b 70. c 71. d 72. d 73. b 74. e 75. a 76. d 77. a 78. c 79. b 80. e 81. a 82. c 83. b 84. d 85. T 86. F, Hb carries O2, CO2, H+ 87. T 88. T 89. T 90. T 91. T 92. T 93. e 94. e 95. e 96. a 97. c 98. b 99. e 100. e 101. c 102. d 103. a 104. e 105. b 106. c 107. T 108. d 109. b 110. e 111. e 112. b 113. c 114. a 115. c 116. b 117. F, cardiac impulse across the heart 118. T 119. F, SA node 120. F, after 121. T 122. T 123. F, right atrium 124. T 125. F, systemi 126. T 127. F, each minute 128. T 15