Chapter 21

381) The coronary artery found in the coronary sulcus is (the) a) posterior interventricular artery. b) circumflex artery. c) LAD. d) anterior interventricular artery. e) none of the above

b) circumflex artery.

363) Blood is supplied to the muscle of the heart through the a) interventricular septum. b) coronary arteries. c) cardiac sinus. d) conus arteriosus. e) pulmonary arteries.

b) coronary arteries.

345) Functions of the endocardium include a) covering the interatrial septum. b) covering the inner surfaces of the heart, including the valves. c) forming the atria and ventricles of the heart. d) covering the outer surface of the heart. e) all of the above.

b) covering the inner surfaces of the heart, including the valves

396) At rest the heart rate is usually by parasympathetic control. a) unchanged b) decreased c) increased d) shut down e) none of the above

b) decreased

344) The reinforcing layer of the pericardium is the layer. a) visceral b) fibrous c) sutural d) parietal e) epicardial

b) fibrous

348) Cardiac muscle cells do not need to contract. a) ATP b) nervous stimulation c) sodium d) potassium e) calcium

b) nervous stimulation

341) The epicardium is also called the a) parietal pericardium. b) visceral pericardium. c) fibrous pericardium. d) pericardial cavity. e) pericardial sac.

b) visceral pericardium

400) Which of the following conditions would be caused if the amount of blood entering the ascending aorta with each contraction of the heart were increased? a) Stimulation by the sympathetic nervous system would accompany this change. b) The atrioventricular valves would not close. c) The amount of blood entering the right atrium of the heart would be increased. d) The heartbeat would be speeded up by the parasympathetic nervous system. e) The amount of blood sent to the lungs for oxygenation would decrease.

c) The amount of blood entering the right atrium of the heart would be increased.

385) The most important factor in ensuring that blood moves in correct order through the heart is (the) a) strength of the contraction of the different parts of the myocardium. b) location of the main electrical conduction node. c) amount of blood in the chambers. d) the timing of atrial and ventricular systole. e) none of the above.

c) amount of blood in the chambers.

382) Which of the following empties directly into the right atrium? a) small cardiac vein b) middle cardiac vein c) anterior cardiac veins d) great cardiac vein e) none of the above

c) anterior cardiac veins

397) Which of the following is a major component of the conduction system located in the interventricular septum? a) AV node b) SA node c) bundle branches d) Purkinje fibers e) none of the above

c) bundle branches

367) The superior end of the right ventricle near the pulmonary valve is called (the) a) ligamentum arteriosum. b) pulmonary trunk. c) conus arteriosus. d) auricle. e) all of the above.

c) conus arteriosus.

395) Structures in the heart that establish the rate of contraction are called a) the chordae tendineae. b) Purkinje fibers. c) nodes. d) conducting fibers. e) none of the above.

c) nodes.

340) The heart wall is composed of layers of tissues. a) 5 b) 4 c) 2 d) 3 e) 1

d) 3

394) Pacemaker cells depolarize about a) 120-140 times per minute. b) 40-50 times per minute. c) 60-70 times per minute. d) 80-100 times per minute. e) None of the above apply to pacemaker cell depolarization.

d) 80-100 times per minute.

354) The heart has the unique ability to change its workload. On average the heart can pump between and liters of blood per minute. a) 10; 20 b) 2; 20 c) 5; 50 d) 1; 3 e) 5; 30

e) 5; 30

360) Grooves on the external surface of the heart that divide the right and left ventricles include the a) lateral sulcus. b) posterior interventricular sulcus. c) coronary fissure. d) anterior interventricular sulcus. e) B and D.

e) B and D.

372) Which of the following valves is assisted in functioning by the papillary muscles? a) left atrioventricular valve b) right atrioventricular valve c) tricuspid valve d) bicuspid valve e) all of the above

e) all of the above

357) The inferior tip of the heart is the a) pulmonary surface. b) sternocostal surface. c) anterior surface. d) base. e) apex.

e) apex.

346) Cardiac muscle differs from other muscle tissue in a) having striations. b) having fibers connected to one another at intercalated disks. c) having fewer mitochondria. d) having larger sized fibers than other striated muscles. e) no ways; it is not unusual.

b) having fibers connected to one another at intercalated disks.

380) Which of the following is not typically supplied with blood by the right coronary artery? a) right ventricle. b) the conducting system. c) most of the left atrium d) posterior heart wall. e) right atrium.

c) most of the left atrium

369) The right ventricle pumps blood into the a) vena cava. b) pulmonary semilunar valves. c) pulmonary veins. d) aorta. e) pulmonary arteries.

e) pulmonary arteries.

377) When a clot forms in a coronary vessel and obstructs blood flow to the muscle, the condition is referred to as a(n) a) pulmonary embolism. b) myocardial infarction. c) coronary thrombosis. d) angina pectoris. e) none of the above.

c) coronary thrombosis.

337) The volume of blood pumped by the heart is a) dependent on what activities a person engages in. b) regulated by the nervous system. c) always approximately 5 liters per minute. d) A and B e) B and C

d) A and B

399) How would the activity of the heart be affected if there were a total blockage of the AV node? a) The electrical stimuli from the SA node would be normal, but the rate of contraction of the ventricles would slow or be irregular. b) The heart rate would be unaffected. c) The heart rate would slow dramatically, and become extremely irregular, contracting only when the ventricles became overfilled. d) The heart rate would increase. e) The heart would cease to contract.

a) The electrical stimuli from the SA node would be normal, but the rate of contraction of the ventricles would slow or be irregular.

376) Which of the following is true of the coronary arteries? a) They originate at the base of the aorta and are the first branch off this vessel. b) They open and close in pulsation with the contraction and relaxation of the heart ventricles. c) Together they supply part of the heart muscle with oxygen. d) They branch off the pulmonary veins. e) None of the above are true.

a) They originate at the base of the aorta and are the first branch off this vessel.

388) The QRS complex of the electrocardiogram occurs when a) depolarization of the ventricles occurs. b) the atria depolarize. c) repolarization of the ventricles occurs. d) repolarization of the atria occurs. e) none of the above occurs.

a) depolarization of the ventricles occurs.

366) The left ventricle is associated with all of the following except the a) pulmonary trunk. b) trabeculae carneae. c) papillary muscles. d) aorta. e) bicuspid valve.

a) pulmonary trunk.

370) The first heart sound, otherwise called the "lubb," signals (the) a) start of ventricular contraction and the closing of the atrioventricular valves and the opening of the semilunar valves. b) turbulence generated at the start of the filling of the atria. c) start of atrial contraction. d) start of ventricular filling, when the semilunar valves close. e) none of the above.

a) start of ventricular contraction and the closing of the atrioventricular valves and the opening of the semilunar valves.

383) The phase of the cardiac cycle during which each chamber contracts and pushes blood into an adjacent chamber is a) systole. b) relaxation. c) diastole. d) ejection. e) none of the above.

a) systole.

347) One of the major differences between skeletal muscle and cardiac muscle is that cardiac muscle a) needs Ca2+ to contract. b) lacks a triad. c) is striated. d) has myosin and actin. e) has the attributes of A and B.

b) lacks a triad.

364) The left atrium receives blood from the a) mitral valve. b) pulmonary veins. c) coronary arteries. d) pulmonary trunk. e) aorta.

b) pulmonary veins.

365) The left ventricle a) pumps blood out of the heart to the pulmonary circuit. b) sends blood out through the aortic semilunar valve to the systemic circulation. c) receives blood from the left atrium through the tricuspid valve. d) has thinner muscular walls than does the right ventricle. e) does all of the above.

b) sends blood out through the aortic semilunar valve to the systemic circulation.

392) During their period of systole, the inner volume of the atrial chambers a) does not change. b) increases, as does the volume in the auricles. c) decreases. d) remains the same, but the auricles enlarge rapidly. e) does none of the above.

c) decreases.

386) During one cardiac cycle the heart spends most of its time in a) fibrillation. b) contraction. c) diastole. d) systole. e) none of the above states.

c) diastole.

391) The chambers of the heart fill during a) maximum contraction. b) atrial systole. c) diastole. d) systole. e) none of the above.

c) diastole.

375) The main pacemaker region of the heart is a) able to cause the muscle to begin to contract at the apex. b) able to cause the atria and ventricles to contract simultaneously. c) in the wall of the right atrium. d) electrically active nodal tissue located in the wall of the left ventricle. e) in the interventricular septum.

c) in the wall of the right atrium.

361) Prominent muscular ridges that run along the inner surface of the auricle and across the adjacent atrial wall are the a) trabeculae carneae. b) chordae tendineae. c) pectinate muscles. d) papillary muscles. e) foramen ovale.

c) pectinate muscles.

384) Valves of the heart open and close due to a) contraction of papillary muscles. b) timing sequences. c) pressure changes. d) electrical signals. e) none of the above.

c) pressure changes.

350) The connective tissues of the heart a) consist only of many dense collagen fibers. b) do not join the muscle fibers to the fibrous skeleton of the heart. c) provide a strong fibrous cross-linkage system wrapping adjacent muscle cells together. d) have the attributes of A and C. e) have none of the above attributes.

c) provide a strong fibrous cross-linkage system wrapping adjacent muscle cells together.

371) The moderator band is located in the a) left atrium. b) right atrium. c) right ventricle. d) left ventricle. e) interventricular sulcus.

c) right ventricle

335) Blood that is transported to and from all of the tissues of the body with the exception of the lungs is in the a) arterial circulation. b) pulmonary circuit. c) systemic circulation. d) venous circulation. e) portal circulation.

c) systemic circulation

336) The ability of the blood to supply oxygen and remove carbon dioxide from the tissues depends upon a) the number of white blood cells in the circulation. b) the rate at which platelets are manufactured. c) the ability of the blood to remain in constant motion. d) the osmotic balance, as controlled by the kidneys. e) the diameter of the capillaries.

c) the ability of the blood to remain in constant motion.

355) Analysis of an ECG can reveal a) the volume of blood passing through the heart. b) damage to the coronary vessels. c) the condition of the conducting system. d) the sequence of the valves opening and closing. e) none of the above.

c) the condition of the conducting system.

378) If a small blood clot passes through the heart and heart vessels, where is it most likely to cause damage if it becomes immobilized? a) the aorta b) the left ventricle c) the left coronary artery d) the right atrial chamber

c) the left coronary artery

393) Which of the chambers of the heart can generate the greatest pressure? a) the right atrium b) the left atrium c) the left ventricle d) the right ventricle e) Both ventricles create greater pressures simultaneously than do the atria.

c) the left ventricle

353) During ventricular systole, the a) atria are contracting. b) the ventricles are filling. c) pressure in the ventricles declines. d) AV valves are closed. e) ventricles are relaxed.

d) AV valves are closed.

374) Which of the following is true of the contraction of the heart? a) The ventricles contract first, followed by the atria. b) The muscle obtains the beat from the pacemaker region exclusively. c) The contractions do not occur in any specific repeatable sequence each time. d) Cardiac contractions are coordinated by specialized conductive cardiac muscle fibers. e) None of the above are true.

d) Cardiac contractions are coordinated by specialized conductive cardiac muscle fibers.

387) In terms of time, at rest one cardiac cycle lasts a) about a half second. b) 5 seconds. c) about 1.5 seconds. d) a little under 1 second. e) none of the above amounts of time.

d) a little under 1 second.

349) Cardiac muscle cells obtain energy almost exclusively through a) glycolysis. b) anaerobic pathways. c) protein stores. d) aerobic respiration. e) the Krebs cycle.

d) aerobic respiration.

373) Which of the following is an incorrect association? a) atrioventricular → mitral valve b) atrioventricular → tricuspid valve c) semilunar → pulmonary valve d) atrioventricular → aortic valve e) None of the above are incorrect.

d) atrioventricular → aortic valve

356) The border between the atria and the ventricles is a) marked by the interventricular sulci. b) at the midsagittal plane. c) impossible to identify externally. d) marked by the coronary sulcus. e) none of the above.

d) marked by the coronary sulcus.

398) Papillary muscles receive a signal to contract from (the) a) Purkinje fibers. b) AV node. c) bundle branches. d) moderator band. e) none of the above.

d) moderator band.

342) Most of the thickness of the heart wall is the a) parietal and visceral layers of the epicardium. b) fibrous pericardium. c) endocardium d) myocardium. e) connective tissue.

d) myocardium

343) The tough structure that surrounds the heart and helps prevent overfilling is the a) fibrous pericardium. b) epicardium. c) mediastinum. d) pericardial sac. e) more than one of the above.

d) pericardial sac.

379) The most serious place for a blockage of a coronary artery is a) the right marginal branch of the right coronary artery. b) the posterior interventricular artery. c) the circumflex branch of the left coronary artery. d) the left coronary artery. e) none of the above.

d) the left coronary artery.

352) The electrical activity of a cardiac muscle fiber a) will cause the rate of heart muscle contraction to increase. b) will trigger an all-or-none response in all other cardiac fibers. c) will cause contraction of that cell and several others. d) will stimulate the electrical conduction system of the heart. e) will do none of the above.

d) will stimulate the electrical conduction system of the heart.

359) The grooves on the outside of the heart contain a) anastomoses. b) coronary arteries. c) fat. d) cardiac veins. e) all of the above.

e) all of the above.

390) Nodal activity of the heart may be influenced or modified by a) the parasympathetic component of the autonomic nervous system. b) either the SA node or the AV node, but no other system. c) the sympathetic component of the autonomic nervous system. d) hormones secreted by the lungs. e) both A and C.

e) both A and C.

358) Externally the posterior and inferior portions of the left ventricle form the a) left border. b) right border. c) superior border. d) sternocostal surface. e) diaphragmatic surface.

e) diaphragmatic surface.

351) The fibrous skeleton of the heart functions to a) maintain the shape of the heart. b) strengthen and help prevent overexpansion of the heart. c) help distribute the force of contraction of the heart. d) provide an anchor for the heart valves. e) do all of the above.

e) do all of the above.

368) The thickest part of the heart muscle is that of the a) right ventricle. b) interventricular septum. c) right atrium. d) left atrium. e) left ventricle.

e) left ventricle.

362) Blood travels from the right atrium to the right ventricle through the a) mitral valve. b) semilunar valve. c) fossa ovalis. d) conus arteriosus. e) tricuspid valve.

e) tricuspid valve.