ANATOMY CH. 21 --The Heart

C) syncytium

Because cardiac muscles are mechanically, chemically, and electrically connected to one another, cardiac muscle tissue functions like a single enormous muscle cell. For this reason, it is called a functional ________. A) sulcus B) inclusion C) syncytium D) intercalation E) triad

E) aortic valve

Blood exiting the left ventricle must pass through the ________ valve. A) mitral B) pulmonary C) tricuspid D) bicuspid E) aortic

C) pulmonary valve

Blood leaves the right ventricle through the ________ valve to reach the capillaries supplying the lungs. A) aortic B) mitral C) pulmonary D) tricuspid E) bicuspid

C) systemic circuit

Blood that occurs to and from all of the tissues of the body, with the EXCEPTION of the lungs, is transported in the ________. A) infundibular circuit B) pulmonary circuit C) systemic circuit D) hepatic portal circuit E) arterial circle of Willis

D) intercalated discs

Cardiac muscle cells differ from skeletal muscle fibers in that the cardiocytes are uniquely interconnected by (the) ________. A) sarcoplasmic reticulum B) Z discs C) gap junctions D) intercalated discs E) T tubules

B) aerobic respiration

Cardiac muscle cells obtain energy almost exclusively through ________. A) anaerobic pathways B) aerobic respiration C) glycolysis D) the Krebs cycle E) protein reserves

D) diastole

During one cardiac cycle, the ventricles spend most of their time in ________. A) systole B) contraction C) fibrillation D) diastole E) depolarization

E) the ventricles are filling

During the late stages of ventricular diastole, the ________. A) atria are contracting B) AV valves are closed C) ventricles are contracting D) pressure in the ventricles does not change E) the ventricles are filling

CARDITIS is a general term for inflammation of the heart. Clinical conditions resulting from cardiac infection are usually identified by the primary site of the infection. For example, infections that affect the endocardium produce symptoms of ENDOCARDITIS, a condition that damages primarily the chordae tendineae and heart valves; the mortality rate may reach 21-35 percent. The most severe complications of endocarditis result from the formation of blood clots on the damaged surfaces.These clots subsequently break free, entering the bloodstream as drifting emboli that may cause strokes, heart attacks, or kidney failure. The destruction of heart valves by the infection may lead to valve leakage, heart failure, and death. --MYOCARDITIS, or inflammation of the heart muscle, can be caused by bacteria, viruses, protozoans, or fungal pathogens that either attack the myocardium directly or produce toxins that damage the myocardium. The sarcolemma of infected heart muscle cells become facilitated, and the heart rate may rise dramatically. Over time, abnormal contractions may appear and the heart muscle weakens; these problems may eventually prove fatal.

ESSAY: Q: Describe the differences between carditis, endocarditis, and myocarditis?

A: In a myocardial infarction (MI), or heart attack, the coronary circulation becomes blocked and the cardiac muscle cells die from lack of oxygen. The affected tissue then degenerates, creating a nonfunctional area known as an infarct. --Heart attacks most often result from severe coronary artery disease (CAD). The consequences depend on the site and nature of the circulatory blockage. If it occurs near the base of one of the coronary arteries, the damage will be widespread and the heart will probably stop beating. IF the blockage involves one of the smaller arterial branches, the individual may survive the immediate crisis, but there are many potential, and unpleasant, complications. As scar tissue forms in the damaged area, the heartbeat may become irregular and less effective as a pump, and other vessels can become constricted creating additional cardiovascular problems such as angina.

ESSAY: A patient is admitted to the emergency room of a hospital complaining of chest pain and shortness of breath. Upon receiving the test results, it is determined that the individual is experiencing a myocardial infarction (MI). What anatomical changes occur during this condition, and what is/are the likely consequence(s)?

A: Cardiac arrhythmias are abnormal cardiac rhythms, which range from inconsequential to lethal. If arrhythmias are occasional and brief in duration, they are rarely of any importance. However,if an arrhythmia persists, or occurs frequently, it merits medical attention. --In clinical diagnosis, arrhythmias are classified as follows: (1) Alterations in heart rate, with normal nodal and conducting pathway function. These conditions, which usually indicate abnormal function at the SA node and atria,are often relatively harmless and may go undetected. Paroxysmal atrial tachycardia (PAT), premature atrial contraction (PAC), atrial flutter, and atrial fibrillation are clinical conditions of this classification. They are not considered very dangerous, unless they are prolonged or associated with some more serious indications of cardiac damage, such as CAD or valve problems. (2) Abnormal origination or distribution of the cardiac action potential within the ventricles. These conditions are dangerous and potentially lethal.Premature ventricular contractions (PVCs), ventricular tachycardia (VT or V-tach),and ventricular fibrillation (VF) are conditions that result in abnormal ventricular activity, which directly affects cardiac output. Many of these ventricular arrhythmias are potentially lethal.

ESSAY: Describe cardiac arrhythmias and briefly discuss their different clinical classifications.

Anatomically, a heart murmur occurs when the cusps of the mitral (or bicuspid) valve do not close properly. The problem may be caused by abnormally long (or short) chordae tendineae or by defective papillary muscles. Because the valve does not work perfectly, some regurgitation may occur during left ventricular systole. The surges, swirls,and eddies that occur during regurgitation create a rushing, gurgling sound known as a heart murmur. In most cases, affected individuals are completely asymptomatic, and they live normal, healthy lives unaware of any circulatory malfunction. However, regurgitation may increase the risk of valve infection after some dental or medical procedures.

ESSAY: If a woman is diagnosed as having a heart murmur, what anatomical condition does she have, and how does it affect heart function?

Angina pectoris is one of the first symptoms of coronary artery disease (CAD). In the most common form of angina, temporary insufficiency of oxygen delivery and ischemia develop when the workload of the heart increases. Although the individual may feel comfortable at rest, any unusual exertion or emotional stress can produce a sensation of pressure, chest constriction, and pain that may radiate from the sternal area to the arms, back, and neck. --Angina can often be controlled by a combination of drug treatment and changes in lifestyle, such as limiting strenuous activity and stressful situations, consuming a diet low in fat, and quitting smoking. Surgical treatment involves balloon angioplasty in which a catheter tip contains an inflatable balloon. Once in position, the balloon is inflated, compressing the plaque against the vessel walls. This procedure works best on small (under 10 mm), soft plaques. Because restenosis (or repeated narrowing) may develop, metal stents (or sleeves) can often be placed into the artery to hold it open.

ESSAY: What is angina pectoris and what is one of the least invasive surgical procedures used to relieve such a condition?

The procedure is called coronary artery bypass graft (CABG) surgery. It involves taking a small section from either a small artery (often the internal thoracic artery) or a peripheral vein (such as a branch of the femoral vein) and implanting it in a region around the heart to create a detour (bypass) around the obstructed portion(s) of a coronary artery. As many as four of the coronary arteries can be rerouted this way in a single operation. The procedures are named according to the number of vessels repaired, so one speaks of single, double, triple, or quadruple CABG operations. Current recommendations are that CABG surgery should be reserved for cases of severe angina that do not respond to other treatments.

ESSAY: What is the major surgical procedure used to treat obstructed regions in the coronary circulation of the heart?

D) diaphragmatic surface

Externally, the posterior and inferior portions of the left ventricle form the ________. A) sternocostal surface B) right border C) left border D) diaphragmatic surface E) superior border

B) Sinoatrial node (SA Node)

Identify the structure(s) indicated by Label A. A) AV bundle B) Sinoatrial node C) Internodal pathways D) Atrioventricular node E) Right bundle branch

D) Aortic arch

Identify the structure(s) indicated by Label A. A) Brachiocephalic trunk B) Descending aorta C) Pulmonary trunk D) Aortic arch E) Ascending aorta

E) Left common carotid artery

Identify the structure(s) indicated by Label A. A) Left subclavian artery B) Ascending aorta C) Brachiocephalic trunk D) Pulmonary trunk E) Left common carotid artery

C) Pulmonary artery

Identify the structure(s) indicated by Label A. A) Pulmonary vein B) Left subclavian artery C) Pulmonary artery D) Aortic arch E) Brachiocephalic trunk

B) Esophagus

Identify the structure(s) indicated by Label A. A) Trachea B) Esophagus C) Pharynx D) Larynx E) Glottis

D) Pulmonary valve

Identify the structure(s) indicated by Label AA. A) Tricuspid valve B) Aortic valve C) Mitral valve D) Pulmonary valve E) Bicuspid valve

A) Brachiocephalic trunk

Identify the structure(s) indicated by Label B. A) Brachiocephalic trunk B) Pulmonary trunk C) Left common carotid artery D) Pulmonary artery E) Left subclavian artery

A) Brachiocephalic trunk

Identify the structure(s) indicated by Label B. A) Brachiocephalic trunk B) Superior vena cava C) Ascending aorta D) Pulmonary artery E) Pulmonary trunk

A) Internodal pathways

Identify the structure(s) indicated by Label B. A) Internodal pathways B) AV bundle C) Purkinje fibers D) Moderator bands E) Bundle branches

D) Pulmonary veins

Identify the structure(s) indicated by Label B. A) Left common carotid arteries B) Pulmonary arteries C) Left subclavian artery D) Pulmonary veins E) Venae cavae

E) Pleural cavity

Identify the structure(s) indicated by Label B. A) Pericardial cavity B) Visceral pericardium C) Peritoneal cavity D) Parietal pericardium E) Pleural cavity

A) Atrioventricular node (AV Node)

Identify the structure(s) indicated by Label C. A) Atrioventricular node B) Right bundle branch C) Moderator band D) AV bundle E) Sinoatrial node

D) Ascending aorta

Identify the structure(s) indicated by Label C. A) Pulmonary artery B) Inferior vena cava C) Pulmonary vein D) Ascending aorta E) Superior vena cava

C) Bronchus of lung

Identify the structure(s) indicated by Label C. A) Pulmonary artery B) Pulmonary vein C) Bronchus of lung D) Superior vena cava E) Inferior vena cava

E) Superior vena cava

Identify the structure(s) indicated by Label C. A) Pulmonary trunk B) Pulmonary artery C) Inferior vena cava D) Ascending aorta E) Superior vena cava

A) Pulmonary artery

Identify the structure(s) indicated by Label D. A) Pulmonary artery B) Superior vena cava C) Pulmonary vein D) Inferior vena cava E) Bronchus of lung

C) Superior vena cava

Identify the structure(s) indicated by Label D. A) Pulmonary trunk B) Brachiocephalic trunk C) Superior vena cava D) Pulmonary vein E) Inferior vena cava

C) Pulmonary arteries

Identify the structure(s) indicated by Label D. A) Pulmonary veins B) Carotid arteries C) Pulmonary arteries D) Brachiocephalic trunk E) Subclavian arteries

E) AV bundle

Identify the structure(s) indicated by Label D. A) Sinoatrial node B) Purkinje fiber C) Internodal pathway D) Moderator band E) AV bundle

C) Left subclavian artery

Identify the structure(s) indicated by Label DD. A) Ligamentum arteriosum B) Brachiocephalic trunk C) Left subclavian artery D) Ascending aorta E) Left common carotid artery

A) Coronary sinus

Identify the structure(s) indicated by Label E. A) Coronary sinus B) Descending aorta C) Pulmonary artery D) Inferior vena cava E) Pulmonary vein

B) Ascending aorta

Identify the structure(s) indicated by Label E. A) Pulmonary trunk B) Ascending aorta C) Superior vena cava D) Descending aorta E) Aortic arch

E) Ventricle

Identify the structure(s) indicated by Label F. A) Atrium B) Aortic arch C) Auricle D) Coronary sinus E) Ventricle

C) Fossa ovalis

Identify the structure(s) indicated by Label F. A) Conus arteriosus B) Ductus venosus C) Fossa ovalis D) Coronary sinus E) Ligamentum arteriosum

E) Atrium

Identify the structure(s) indicated by Label F. A) Coronary sulcus B) Interventricular sulcus C) Ventricle D) Ligamentum arteriosum E) Atrium

D) Phrenic nerve

Identify the structure(s) indicated by Label F. A) Pulmonary cavity B) Vagus nerve C) Aorta D) Phrenic nerve E) Pulmonary trunk

D) Right bundle branch

Identify the structure(s) indicated by Label F. A) Purkinje fiber B) Left bundle branch C) Internodal pathway D) Right bundle branch E) Moderator band

C) Moderator band

Identify the structure(s) indicated by Label G. A) AV bundle B) Atrioventricular node C) Moderator band D) Sinoatrial node E) Bundle branch

E) Superior vena cava

Identify the structure(s) indicated by Label G. A) Brachiocephalic trunk B) Aorta C) Inferior vena cava D) Pulmonary trunk E) Superior vena cava

A) Coronary sinus

Identify the structure(s) indicated by Label G. A) Coronary sinus B) Conus arteriosus C) Ligamentum arteriosum D) Ductus venosus E) Fossa ovalis

A) Atrium

Identify the structure(s) indicated by Label H. A) Atrium B) Pericardial cavity C) Ventricle D) Aortic arch E) Esophagus

B) Ventricle

Identify the structure(s) indicated by Label H. A) Auricle B) Ventricle C) Coronary sulcus D) Atrium E) Interventricular sulcus

B) Purkinje fibers

Identify the structure(s) indicated by Label H. A) Moderator bands B) Purkinje fibers C) Bundle branches D) Internodal pathways E) AV bundle

B) Inferior vena cava

Identify the structure(s) indicated by Label I. A) Descending aorta B) Inferior vena cava C) Brachiocephalic trunk D) Superior vena cava E) Pulmonary trunk

A) Pectinate muscles

Identify the structure(s) indicated by Label I. A) Pectinate muscles B) Coronary sinus C) Papillary muscles D) Trabeculae carneae E) Chordae tendineae

E) Conus arteriosus

Identify the structure(s) indicated by Label J. A) Ligamentum arteriosum B) Coronary sinus C) Ductus venosus D) Fossa ovalis E) Conus arteriosus

B) Mediastinum

Identify the structure(s) indicated by Label J. A) Vertebrae B) Mediastinum C) Pleural cavity D) Parietal pericardium E) Rib

D) Tricuspid valve

Identify the structure(s) indicated by Label K. A) Aortic valve B) Mitral valve C) Pulmonary valve D) Tricuspid valve E) Bicuspid valve

A) Auricle

Identify the structure(s) indicated by Label K. A) Auricle B) Interventricular sulcus C) Pectinate muscle D) Ventricle E) Coronary sulcus

D) Parietal pericardium

Identify the structure(s) indicated by Label K. A) Pleural cavity B) Visceral pericardium C) Mediastinum D) Parietal pericardium E) Epicardium

C) Pulmonary trunk

Identify the structure(s) indicated by Label L. A) Aorta B) Superior vena cava C) Pulmonary trunk D) Pulmonary vein E) Brachiocephalic trunk

B) Chordae tendineae

Identify the structure(s) indicated by Label L. A) Papillary muscles B) Chordae tendineae C) Moderator bands D) Trabeculae carneae E) Pectinate muscles

C) Epicardium

Identify the structure(s) indicated by Label L. A) Parietal pericardium B) Pleural cavity C) Epicardium D) Mediastinum E) Endocardium

E) Pericardial cavity

Identify the structure(s) indicated by Label M. A) Peritoneal cavity B) Visceral pericardium C) Pleural cavity D) Parietal pericardium E) Pericardial cavity

D) Papillary muscles

Identify the structure(s) indicated by Label M. A) Trabeculae carneae B) Pectinate muscles C) Chordae tendineae D) Papillary muscles E) Moderator bands

B) Arch of aorta

Identify the structure(s) indicated by Label N. A) Brachiocephalic trunk B) Arch of aorta C) Pulmonary trunk D) Left subclavian artery E) Common carotid artery

A) Ventricle

Identify the structure(s) indicated by Label N. A) Ventricle B) Auricle C) Atrium D) Esophagus E) Mediastinum

D) Atrium

Identify the structure(s) indicated by Label O. A) Chordae tendineae B) Trabeculae carneae C) Ventricle D) Atrium E) Pulmonary trunk

C) Inferior vena cava

Identify the structure(s) indicated by Label O. A) Pulmonary vein B) Pulmonary trunk C) Inferior vena cava D) Pulmonary artery E) Superior vena cava

E) Descending aorta

Identify the structure(s) indicated by Label P. A) Aortic arch B) Inferior vena cava C) Ascending aorta D) Brachiocephalic trunk E) Descending aorta

C) Pulmonary trunk

Identify the structure(s) indicated by Label P. A) Brachiocephalic trunk B) Left common carotid artery C) Pulmonary trunk D) Aorta E) Bronchus of lung

B) Pulmonary vein

Identify the structure(s) indicated by Label Q. A) Ascending aorta B) Pulmonary vein C) Aortic arch D) Pulmonary artery E) Pulmonary trunk

A) Moderator band

Identify the structure(s) indicated by Label Q. A) Moderator band B) Chordae tendineae C) Papillary muscle D) Interventricular septum E) Trabeculae carneae

B) Trabeculae carneae

Identify the structure(s) indicated by Label R. A) Pectinate muscles B) Trabeculae carneae C) Papillary muscles D) Moderator bands E) Chordae tendineae

D) Interventricular septum

Identify the structure(s) indicated by Label S. A) Papillary muscle B) Interatrial septum C) Moderator band D) Interventricular septum E) Pectinate muscle

B) Pulmonary artery

Identify the structure(s) indicated by Label S. A) Superior vena cava B) Pulmonary artery C) Brachiocephalic trunk D) Pulmonary vein E) Aorta

C) Ventricle

Identify the structure(s) indicated by Label T. A) Auricle B) Interatrial septum C) Ventricle D) Interventricular septum E) Atrium

D) Aorta

Identify the structure(s) indicated by Label T. A) Bronchus of lung B) Pulmonary vein C) Pulmonary trunk D) Aorta E) Pulmonary artery

B) Mitral valve

Identify the structure(s) indicated by Label U. A) Bicuspid valve B) Mitral valve C) Tricuspid valve D) Aortic valve E) Pulmonary valve

A) Aortic valve

Identify the structure(s) indicated by Label V. A) Aortic valve B) Pulmonary valve C) Bicuspid valve D) Tricuspid valve E) Mitral valve

E) Interatrial septum

Identify the structure(s) indicated by Label W. A) Interventricular septum B) Papillary muscle C) Moderator band D) Pectinate muscle E) Interatrial septum

D) Pulmonary veins

Identify the structure(s) indicated by Label Y. A) Brachiocephalic trunk B) Pulmonary arteries C) Pulmonary trunk D) Pulmonary veins E) Common carotid arteries

B) regurgitation

If the cusps of an atrioventricular valve are damaged or functionally impaired so that they do not close completely during the normal point in the cardiac cycle, blood may flow backwards. This is called ________. A) ischemia B) regurgitation C) thrombosis D) automaticity E) nodal depolarization

B) the autonomic nervous system

Intrinsic heart rate may be influenced or modified by ________. A) either the SA node or the AV node only, but no other factors B) the autonomic nervous system C) the somatomotor cortex D) hormones secreted by the lungs E) enzymes released from the kidney

C) lacks triads

One of the major differences between skeletal muscle and cardiac muscle is that cardiac muscle ________. A) is striated B) has myosin and actin C) lacks triads D) needs Ca2+ to contract E) has a very large sarcoplasmic reticulum

D) tricuspid

Oxygen-poor blood travels from the right atrium into the right ventricle through the ________ valve. A) bicuspid B) aortic C) mitral D) tricuspid E) pulmonary

C) 80-100 beats per minute

Pacemaker cells of the SA node depolarize and theoretically generate a resting heart rate of approximately ________. A) 60-70 beats per minute B) 55-65 beats per minute C) 80-100 beats per minute D) 45-55 beats per minute E) 110-120 beats per minute

B) moderator band

Papillary muscles of the right ventricle receive a signal to contract from (the) ________. A) left and right bundle branches B) moderator band C) AV node D) Purkinje fibers E) atrioventricular bundles

B) pectinate muscles

Prominent muscular ridges, which extend along the inner surface of the right auricle, across the adjacent anterior wall of the right atrium are called ________. A) moderator bands B) pectinate muscles C) trabeculae carneae D) papillary muscles E) chordae tendineae

A) internodal pathways

Structures in the heart that carry electrical signals from the SA node to the AV node are called ________. A) internodal pathways B) bundle branches C) Purkinje fibers D) chordae tendineae E) moderator bands

TRUE: Arteries always transport blood away from the heart.

T/F: Arteries transport blood away from the heart.

FALSE: Each cardiac contraction follows a precise sequence. At time=0, atrial activation begins when the SA NODE depolarizes.

T/F: Each cardiac contraction follows a precise sequence. At time=0, atrial activation begins when the AV node depolarizes.

FALSE: Each semilunar valve consists of the following: --a ring of connective tissue that attaches to the fibrous skeleton of the heart; --connective tissue cusps, which PREVENT BLOOD FROM BACKFLOW; --and chordae tendineae that attach the margins of the cusps to the papillary muscles of the heart wall.

T/F: Each semilunar valve consists of the following: - a ring of connective tissue that attaches to the fibrous skeleton of the heart; - connective tissue cusps, which function to close the opening between the heart chambers; - and chordae tendineae that attach the margins of the cusps to the papillary muscles of the heart wall.

FALSE: In the cardiac cycle, as atrial systole ends, ventricular SYSTOLE begins and continues until the start of the next cardiac cycle.

T/F: In the cardiac cycle, as atrial systole ends, ventricular diastole begins and continues until the start of the next cardiac cycle.

TRUE: Norepinephrine release produces an increase in both the heart rate and force of contraction through the stimulation of beta receptors on nodal cells and contractile cells.

T/F: Norepinephrine release produces anincrease in both the heart rate and force of contraction through thestimulation of beta receptors on nodal cells and contractile cells.

FALSE: Since the heart is rotated slightly to the left, the anterior surface or sternocostal surface, consists primarily of THE RIGHT VENTRICLE.

T/F: Since the heart is rotated slightly to the left, the anterior surface or sternocostal surface, consists primarily of both atria.

FALSE: The fibrous pericardium IS SUPERFICIAL to the serous pericardium. (The Serous pericardium lies deep to the fibrous pericardium).

T/F: The fibrous pericardium lies deep to the serous pericardium.

TRUE: The fibrous skeleton reinforces the valves and helps prevent over-expansion of the heart.

T/F: The fibrous skeleton reinforces the valves and helps prevent over-expansion of the heart.

TRUE: The myocardium consists of multiple, interlocking layers of cardiac muscle tissue, with associated connective tissue, blood vessels, and nerves.

T/F: The myocardium consists of multiple, interlocking layers of cardiac muscle tissue, with associated connective tissue, blood vessels, and nerves.

TRUE: When the left ventricle contracts, the distance between the base and apex decreases, and the diameter of the ventricular chamber decreases.

T/F: When the left ventricle contracts, the distance between the base and apex decreases, and the diameter of the ventricular chamber decreases.

A) trabeculae carneae

The ________ are a series of irregular muscular folds formed on the internal surface of the ventricles. A) trabeculae carneae B) papillary muscles C) chordae tendineae D) moderator bands E) pectinate muscles

B) pulmonary circuit

The ________ carries blood to and from the gas exchange surfaces of the lungs. A) arterial circle of Willis B) pulmonary circuit C) infundibular circuit D) systemic circuit E) hepatic portal circuit

D) superior border

The ________ of the heart includes the bases of the major vessels. A) right border B) inferior border C) left border D) superior border E) diaphragmatic surface

B) base

The broad, superior portion of the heart is the ________. A) apex B) base C) sternocostal surface D) pulmonary surface E) anterior surface

C) apex

The diaphragm is attached to the inferior, rounded tip of the heart, called the ________, which points laterally. A) base B) inferior border C) apex D) diaphragmatic surface E) left border

C) capillaries

The exchange vessels in the cardiovascular system are called ________. A) veins B) arteries C) capillaries D) venules E) arterioles

E) auricle

The expansible portion of an atrium is called a(n) ________ because it reminded early anatomists of the external ear. A) atrial sinus B) coronary sulcus C) atrial apex D) interatrial groove E) auricle

A) fibrous skeleton

The extensive connective tissue network, which encircles the bases of the pulmonary trunk and aorta and the valves of the heart, is called the ________ of the heart. A) fibrous skeleton B) endocardium C) intercalated network D) pericardium E) pulmonary epicardium

E) All of the answers are correct.

The fibrous skeleton of the heart functions to ________. A) provide elasticity that helps return the heart to its original shape after each contraction B) physically isolating the atrial muscle cells from the ventricular muscle cells C) help distribute the force of contraction of the heart D) reinforcing the heart valves E) All of the answers are correct.

D) autorhythmicity

The inherent ability of cardiac muscle tissue to contract in the absence of neural or hormonal stimulation is called ________. A) threshold B) systole C) diastole D) autorhythmicity E) a cardiac pacemaker

D) fascia adherens

The intercalated disc of cardiac muscle cells possess a specialized form of adhering junction termed a(n) ________. A) desmosome B) macula adherens C) gap junction D) fascia adherens E) CAM

C) pulmonary veins

The left atrium receives oxygen-rich blood from the ________. A) coronary arteries B) venae cavae C) pulmonary veins D) descending aorta E) pulmonary arteries

D) aorta

The left ventricle pumps blood into the systemic circuit through the ________. A) mitral valve B) pulmonary veins C) pulmonary arteries D) aorta E) venae cavae

TRUE: The major branches of the right coronary artery are: - the atrial branches, which supply the right atrium and a portion of the left atrium; - the ventricular branches, which supply the interventricular septum and adjacent portions of the ventricles; and, - the branches to the conducting system, which supply the SA node and the AV node.

The major branches of the right coronary artery are: - the atrial branches, which supply the right atrium and a portion of the left atrium; - the ventricular branches, which supply the interventricular septum and adjacent portions of the ventricles; and, - the branches to the conducting system, which supply the SA node and the AV node.

C) right ventricle

The moderator band is located in the ________. A) left ventricle B) right atrium C) right ventricle D) left atrium E) interatrial sulcus

A) parietal pericardium

The outermost layer of the serous pericardium is termed the ________. A) parietal pericardium B) fibrous pericardium C) visceral pericardium D) endocardium E) epicardium

A) cardiac cycle

The period between the start of one heartbeat and the beginning of the next is a single ________. A) cardiac cycle B) arrhythmia C) diastole D) intermodal pathway E) systole

C) systole

The phase of the cardiac cycle during which each chamber contracts and pumps blood into another heart chamber, or into an arterial trunk, is called ________. A) diastole B) thrombosis C) systole D) relaxation E) ischemia

E) lubrication

The primary function of the pericardial fluid is to provide ________ between the pericardial membranes. A) friction B) impulse stimulation C) pressure D) perforation E) lubrication

E) SA node

The rapidly depolarizing cells, called pacemaker cells, are found in the ________, which is embedded in the posterior wall of the right atrium. A) right bundle branch B) AV node C) left bundle branch D) intermodal pathways E) SA node

A) has thinner muscular walls than does the left ventricle

The right ventricle ________. A) has thinner muscular walls than does the left ventricle B) receives blood from the left atrium through the tricuspid valve C) pumps blood out of the heart to the systemic circuit D) pumps blood out of the heart through the aortic semilunar valve E) is connected to the pulmonary veins

E) embedded in the posterior wall of the right atrium, near the entrance of the superior vena cava

The sinoatrial node, or cardiac pacemaker, is ________. A) electrically active nodal tissue located in the wall of the left ventricle B) embedded in the anterior two-thirds of the interventricular septum C) able to cause the atria and ventricles to contract simultaneously D) able to cause the cardiac muscle to begin to contract at the apex E) embedded in the posterior wall of the right atrium, near the entrance of the superior vena cava

B) conus arteriosus

The superior end of the right ventricle, which tapers to a smooth-walled pouch and ends at the pulmonary valve is called (the) ________. A) auricle B) conus arteriosus C) aortic sinus D) ligamentum arteriosum E) fossa ovalis

C) epicardium

The visceral pericardium is also called the ________. A) endocardium B) parietal pericardium C) epicardium D) myocardium E) fibrous pericardium

C) anastomoses

There are many interconnections between the arterial branches of the coronary circulation, which function to maintain a constant blood supply to the muscle of the heart. These connections are called ________. A) syncytium B) intercalation C) anastomoses D) prolapse E) autorhythmicity

D) pressure changes

Valves of the heart open and close due to ________. A) contraction of papillary muscles B) timing sequences C) electrical signals D) pressure changes E) None of the answers are correct.

D) right marginal branch

Which branch(es) of the right coronary artery extends toward the apex along the anterior surface of the right ventricle and continues across the posterior surface of the heart? A) circumflex branch B) posterior interventricular branch C) atrial branches D) right marginal branch E) anterior interventricular branch

B) the left ventricle

Which chamber of the heart can generate the greatest pressure? A) the left atrium B) the left ventricle C) the right atrium D) the right ventricle E) Both ventricles create greater pressures equally and simultaneously than do the atria.

A) small cardiac vein

Which coronary vein receives blood from the posterior surfaces of the right atrium and ventricle? A) small cardiac vein B) middle cardiac vein C) coronary sinus D) anterior cardiac vein E) posterior vein of left ventricle

B) collagen fibers

Which element of the fibrous pericardium binds the base of the heart to the mediastinum? A) reticular fibers B) collagen fibers C) skeletal muscle D) elastic fibers E) cartilage

E) Atrioventricular valves are closed.

Which event occurs during ventricular systole? A) Chordae tendineae are loose. B) Semilunar valves are closed. C) The left ventricle is dilated. D) Papillary muscles are relaxed. E) Atrioventricular valves are closed.

B) Atrial contraction forces a small amount of blood into the relaxed ventricles.

Which event typically occurs at the start of a cardiac cycle? A) Ventricular blood pressure drops until reverse blood flow pushes the cusps of the semilunar valves together. B) Atrial contraction forces a small amount of blood into the relaxed ventricles. C) The semilunar valves open and blood is ejected. D) Ventricular contraction pushes the atrioventricular valves closed. E) The atrioventricular valves opens and the ventricles fill passively.

E) Atrioventricular valves are closed.

Which event typically occurs during the first phase of ventricular systole? A) Semilunar valves are closed. B) All chambers are relaxed. C) Atrioventricular valves are open. D) Semilunar valves are open. E) Atrioventricular valves are closed.

A) coronary sulcus

Which feature marks the border between the atria and the ventricles? A) coronary sulcus B) interatrial groove C) posterior interventricular sulcus D) anterior interventricular sulcus E) atrial appendage

D) pectinate muscles

Which features are described as prominent muscular ridges that extend along the inner surface of the right auricle and across the adjacent anterior wall of the right atrium? A) chordae tendineae B) foramina ovale C) papillary muscles D) pectinate muscles E) trabeculae carneae

B) endocardium

Which is the deepest and innermost layer of the heart wall? A) parietal layer of the epicardium B) endocardium C) myocardium D) fibrous pericardium E) visceral layer of the epicardium

B) acetylcholine—muscarinic receptors on nodal cells and contractile cells

Which of the following associations is correct? A) baroreceptors—sensitivity to dissolved gas concentrations B) acetylcholine—muscarinic receptors on nodal cells and contractile cells C) parasympathetic nervous system—cardiac nerves D) norepinephrine—alpha receptors on nodal cells and contractile cells E) sympathetic nervous system—vagus nerves

A) mitral valve—atrioventricular

Which of the following associations is correct? A) mitral valve—atrioventricular B) pulmonary valve—atrioventricular C) aortic valve—chordae tendineae D) tricuspid valve—semilunar valve E) pulmonary valve—chordae tendineae

C) activation of the sympathetic nervous system

Which of the following conditions would cause an increase in the heart rate? A) activation of the parasympathetic nervous system B) acetylcholine stimulation of nodal cells and contractile cells C) activation of the sympathetic nervous system D) decreased blood concentration of carbon dioxide and increased blood pressure E) decreased blood concentration of oxygen and increased blood pressure

C) anterior cardiac veins

Which of the following drains the anterior surface of the right ventricle and empties directly into the right atrium? A) middle cardiac vein B) great cardiac vein C) anterior cardiac veins D) small cardiac vein E) posterior veins of left ventricle

C) They originate at the base of the aorta and are the first branches off this vessel.

Which of the following is TRUE of the coronary arteries? A) They drain into the right atrium inferior to the opening of the inferior vena cava. B) Together they supply a small portion of the cardiac muscle with oxygen. C) They originate at the base of the aorta and are the first branches off this vessel. D) They open and close in pulsation with the contraction and relaxation of the heart ventricles. E) Blood pressure in these vessels are the lowest found anywhere in the systemic circuit.

E) Cardiac contractions are coordinated by specialized conducting cells, cardiac muscle cells that are incapable of undergoing powerful contractions.

Which of the following is TRUE regarding contractions of the heart? A) The ventricles contract first, followed by the atria. B) The contractions do not occur in any specific or precise sequence each time. C) Cardiac muscle tissue contracts under neural stimulation. D) The rate of cardiac contractions are established by the conducting fibers. E) Cardiac contractions are coordinated by specialized conducting cells, cardiac muscle cells that are incapable of undergoing powerful contractions.

A) bicuspid valve

Which of the following is a feature that is unique to the left atrium? A) bicuspid valve B) fossa ovalis C) tricuspid valve D) foramen ovale E) conus arteriosus

A) distributes the forces of contraction

Which of the following is a function of the fibrous skeleton of the heart? A) distributes the forces of contraction B) provides instructions for cardiac muscle cells to contract C) maintains the energy reserves in the form of glycogen and lipid inclusions D) provides full range mobility to the valves of the heart E) physically connects the atrial muscle cells to the ventricular muscle cells

B) bundle branches

Which of the following is a major component of the conduction system located in the interventricular septum, and extends toward the apex of the heart? A) SA node B) bundle branches C) AV node D) Purkinje fibers E) intermodal pathways

Which of the following is a unique feature of the right ventricle? A) mitral valve B) papillary muscles C) aorta D) pulmonary trunk E) trabeculae carneae

Which of the following is a unique feature of the right ventricle? A) mitral valve B) papillary muscles C) aorta D) pulmonary trunk E) trabeculae carneae

E) coronary sinus

Which of the following structures is a large, thin-walled vein that lies in the posterior portion of the coronary sulcus? A) posterior veins of left ventricle B) middle veins of left ventricle C) aortic sinus D) great cardiac vein E) coronary sinus

E) inferior vena cava

Which structure delivers venous blood from the tissues and organs of the abdominal and pelvic cavities, and from the lower limbs? A) coronary veins B) pulmonary trunk C) superior vena cava D) fossa ovalis E) inferior vena cava

C) right ventricle

Which structure makes up a large percentage of the sternocostal surface of the heart? A) right atrium B) left atrium C) right ventricle D) left ventricle E) pulmonary trunk

E) right atrium

Which structure receives blood from the systemic circuit? A) left ventricle B) pulmonary veins C) right ventricle D) left atrium E) right atrium

A) gap junctions

Which structures are responsible for creating a direct electrical connection between cardiac muscle cells? A) gap junctions B) maculae adherens C) intercalated discs D) desmosomes E) fascia adherens

C) left coronary artery

Which vessel gives rise to a circumflex branch and an anterior interventricular branch? A) left marginal branch B) coronary sinus C) left coronary artery D) posterior descending artery E) right coronary artery

B) Cardiocytes

________ are individual cardiac muscle cells, which are relatively small, averaging 10-20 µm in diameter and 50-100 µm in length. A) Fibrocytes B) Cardiocytes C) Myelocytes D) Chondrocytes E) Osteocytes

B) Bradycardia

________ is the term used to indicate a heart rate that is slower than normal. A) Cardiac tamponade B) Bradycardia C) Angina D) Tachycardia E) Coronary ischemia

B) Acetylcholine

________ release produces a DECREASE in both the heart rate and force of contraction through the stimulation of muscarinic receptors on nodal cells and contractile cells. A) Dopamine B) Acetylcholine C) Serotonin D) Norepinephrine E) Cholecystokinin