ch 19 (FINAL EXAM)

Select all that occur during the plateau phase of an action potential on a cardiac muscle cell. A) Calcium is entering the cell. B) Potassium is exiting the cell. C) Sodium is entering the cell. D) Calcium is exiting the cell.

A) Calcium is entering the cell. B) Potassium is exiting the cell.

Which of the cardiovascular system's circuits has deoxygenated blood in its arteries? A) Pulmonary circuit B) Visceral circuit C) Coronary circuit D) Systemic circuit

A) Pulmonary circuit

Which describes the endocardium? a: Has single layer of epithelium b: Has layer of areolar connective tissue c: Epithelial cells are squamous d: Epithelial cells are cuboidal e: Has layer of adipose connective tissue f: Has patches of myocardium A) a, b, c B) a, b, d C) a, d, e D) a, b, c, e E) a, e, f

A) a, b, c

Just prior to atrial contraction, A) all four chambers are at rest and AV valves are open. B) all four chambers are at rest and AV valves are closed. C) all four chambers are contracting and all valves are open. D) both ventricles are contracting and blood is being ejected into the major arteries. E) both atria are contracting and blood is being ejected into the major arteries.

A) all four chambers are at rest and AV valves are open.

The pulmonary trunk receives blood from the right ventricle and conducts it toward the lung. The pulmonary trunk is a(n) A) artery. B) capillary. C) vein.

A) artery.

The serous fluid within the pericardial cavity works to A) lubricate membranes of the pericardium. B) slow the heart rate. C) equalize the pressure in the great vessels. D) eliminate blood pressure spikes. E) All of the choices are correct.

A) lubricate membranes of the pericardium.

Someone with tachyarrhythmia would be expected to show an abnormally A) small Q-T interval. B) large P-R interval. C) large R-R interval. D) high amplitude P wave.

A) small Q-T interval.

Which correctly describes the heart's apex? A)Projects slightly anteroinferiorly toward the left side of the body. B)Projects slightly anteroinferiorly toward the right side of the body. C)Projects slightly posteroinferiorly toward the left side of the body. D)Projects slightly posteroinferiorly toward the right side of the body. E)Projects slightly posteroinferiorly toward the midline of the body.

A)Projects slightly anteroinferiorly toward the left side of the body.

Sympathetic innervation of the heart arises from the ________ segments of the spinal cord. A)T1-T5 B)T3-T8 C)T5-T10 D)T6-T11 E)T11-L2

A)T1-T5

Which prenatal structure forms the ascending aorta and pulmonary trunk? A)Truncus arteriosus B)Sinus venosus C)Primitive atrium D)Primitive ventricle E)Conus cordis

A)Truncus arteriosus

Someone with a heart block would have A)a long P-R interval. B)a long T-P interval. C)a short P-R interval. D)a short T-P interval.

A)a long P-R interval.

Which are differences between cardiac muscle tissue and skeletal muscle tissue? a: The sarcoplasmic reticulum in cardiac muscle is less extensive. b: The sarcoplasmic reticulum in cardiac muscle is more organized. c: Cardiac muscle has intercalated discs; skeletal muscle does not. d: Cardiac muscle has 1 or 2 nuclei per cell; skeletal muscle has multiple nuclei per cell. e: Cardiac muscle has more well-defined terminal cisternae. A)a, c, d B)a, c, e C)b, c, e D)a, b, e E)b, d, e

A)a, c, d

The great cardiac vein runs alongside the A)anterior interventricular artery. B)posterior interventricular artery. C)right marginal artery. D)aorta. E)coronary sinus

A)anterior interventricular artery.

During the plateau phase of a cardiac muscle cell's action potential, the membrane stays A)depolarized as potassium exits and calcium enters. B)depolarized as potassium enters and calcium exits. C)repolarized as sodium enters and calcium exits. D)hyperpolarized as sodium and calcium exit. E)hyperpolarized as potassium enters and calcium exits

A)depolarized as potassium exits and calcium enters.

Blood moves into and then out of a heart chamber because A)it moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle. B)it is under constant pressure, but its movement is dictated by the control of valve openings and closures. C)the veins and arteries constrict and dilate to propel and attract blood. D)All of the choices are correct.

A)it moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle

As blood is pumped out of the heart and into the major arteries leaving the heart, it A)pushes against the semilunar valves and opens them. B)pushes against the semilunar valves and closes them. C)fills the cusps of the semilunar valves, causing them to expand and block the backflow ofblood D)pushes against the atrioventricular valves and opens them. E)fills the cusps of the atrioventricular valve causing opening of the bicuspid and closure of the tricuspid.

A)pushes against the semilunar valves and opens them.

The metabolic pathways of cardiac muscle make it A)somewhat susceptible to heart attack, because it relies so exclusively on aerobic metabolism. B)extremely susceptible to heart attack, because it uses such a variety of fuel sources. C)somewhat susceptible to heart attack, because it has so few mitochondria. D)relatively resistant to heart attack, because it uses exclusively anaerobic metabolism. E)relatively resistant to heart attack, because it has a great capacity to accrue oxygen debt.

A)somewhat susceptible to heart attack, because it relies so exclusively on aerobic metabolism.

As with action potentials in other types of cells, the repolarization of cardiac muscle cells involves the A) entrance of calcium through voltage-gated channels. B) exit of potassium through voltage-gated channels. C) entrance of sodium through voltage-gated channels. D) binding of ACh to ACh receptor. E) simultaneous closure of sodium channels and opening of calcium channels.

B) exit of potassium through voltage-gated channels.

The foramen ovale of the fetal heart is an opening in the A) interventricular septum. B) interatrial septum. C) fossa ovalis. D) aorticopulmonary septum. E) tetralogy of Fallot.

B) interatrial septum.

The units for perfusion of blood are typically A) grams per minute. B) milliliters per minute per gram. C) millimiters per hour per kilogram. D) liters per gram. E) beats per minute per gram.

B) milliliters per minute per gram.

Typically, there are __________ papillary muscles that project from the wall of the left ventricle and attach to the tendinous cords that support the left AV valve. A) three B) two C) a highly variable number of D) six E) no

B) two

During a cardiac cycle, how many of the four chambers contract at any one time? A)1 B)2 C)4 D)Highly variable, depending on the heart beat rate E)None of the choices is correct.

B)2

Which layer is made of dense irregular connective tissue? A)Myocardium B)Fibrous pericardium C)Epicardium D)Serous pericardium E)Endocardium

B)Fibrous pericardium

Which vein drains the posterior aspect of the ventricles of the heart? A)Great cardiac vein B)Middle cardiac vein C)Small cardiac vein D)Circumflex vein

B)Middle cardiac vein

From which view is the connection between the pulmonary veins and the heart most visible? A)Anterior view B)Posterior view

B)Posterior view

Which carries oxygenated blood from the lungs to the heart? A)Pulmonary arteries B)Pulmonary veins C)Pulmonary trunk D)Inferior vena cava E)Superior vena cava

B)Pulmonary veins

The tetralogy of Fallot is A)a condition in which the left and right sides of the heart are completely reversed. B)a developmental disorder that is a cardiac septal defect. C)an exceptionally fast heart rate. D)an inadequate cardiac output due to poorly contracting heart chambers. E)occlusion of the left coronary artery.

B)a developmental disorder that is a cardiac septal defect.

Metabolically, cardiac muscle relies on A)aerobic metabolism using glycolysis of glycogen to meet most ATP demands. B)aerobic metabolism using many mitochondria and a rich supply of myoglobin. C)anaerobic metabolism using glycolytic enzymes to quickly generate ATP. D)anaerobic metabolism using myoglobin, creatin kinase, and ketone bodies

B)aerobic metabolism using many mitochondria and a rich supply of myoglobin.

The left and right coronary arteries A)are interconnected with several high-volume anastomoses allowing for well perfusedalternate blood paths. B)are functional end arteries because the blockage of one of them leads to tissue death in the area it supplies.

B)are functional end arteries because the blockage of one of them leads to tissue death in the area it supplies.

To initiate a cardiac muscle cell contraction, calcium A)binds to calmodulin. B)binds to troponin. C)binds to actin. D)binds to the Z-disc. E)binds to tropomyosin.

B)binds to troponin.

Cardiac output is the amount of blood that is pumped A)by a single ventricle in one hour. B)by a single ventricle in one minute. C)by both ventricles in one hour. D)by both ventricles in one minute.E)by the left ventricle into the aorta in one beat.

B)by a single ventricle in one minute.

The membrane of a contractile cardiac muscle cell contains A)no calcium pumps. B)calcium pumps that move calcium out of the cell. C)calcium pumps that move calcium into the cell. D)calcium pumps that open and allow calcium to diffuse down its concentration gradient to reach equilibrium.

B)calcium pumps that move calcium out of the cell.

The membrane of a contractile cardiac muscle cell contains A)fast voltage-gatedsodium channels and fast voltage-gated calcium channels. B)fast voltage-gatedsodium channels and slow voltage-gated calcium channels. C)slow voltage-gatedsodium channels and slow voltage-gated calcium channels. D)slow voltage-gatedsodium channels and fast voltage-gated calcium channels

B)fast voltage-gatedsodium channels and slow voltage-gated calcium channels.

The atrioventricular (AV) node is located in the A)floor of the left atrium. B)floor of the right atrium. C)roof of the left ventricle. D)back wallof the right ventricle. E)back wall of the left ventricle.

B)floor of the right atrium.

Coronary vessels are open when the heart is A)contracting. B)relaxed.

B)relaxed.

Cardiac reserve is A)the potential increase in stroke volume someone would show if they engaged in athletictraining. B)the increase in cardiac output an individual is capable of demonstrating during vigorous exercise. C)the amount of blood left in the heart after the ventricle has contracted during cardiac cycles at rest. D)the blood that the heart uses to nourish its cardiac muscle and does not put into general circulation.

B)the increase in cardiac output an individual is capable of demonstrating during vigorous exercise.

How many half-moon shaped, pocketlike cusps are found in each semilunar valve? A) 1 B) 2 C) 3 D) 4 E) 6

C) 3

What would you expect a cardiologist to recommend if there was substantial occlusion to a patient'sleft coronary artery but not the right coronary artery? A) Because there are multiple alternate paths for blood delivery, the cardiologist would not intervene. B) Because this is a relatively small, unimportant artery, the cardiologist would not intervene. C) Because this is an important artery, and alternate vascular paths are inadequate,the cardiologist would treat the condition. D) Because occlusions require blood to be moved undergreater pressure, the cardiologist would prescribe drugs to raise blood pressure.

C) Because this is an important artery, and alternate vascular paths are inadequate,the cardiologist would treat the condition.

Norepinephrine is considered a positive chronotropic agent because it causes A) less calcium to enter heartcells, which leads to lower risk of heart attack. B) more forceful contractions during each heart rate. C) an increase in the firing rate of SA node cells. D) thyroid hormone to have a steadying effect on heart activity. E) heart cell membrane potentials to become more positive during action potentials.

C) an increase in the firing rate of SA node cells.

The pericardial cavity is between the A) heart muscle and serous pericardium. B) fibrous and serous layers of the pericardium. C) visceral and parietal layers of the serous pericardium. D) parietal and myocardial layers of the fibrous pericardium.

C) visceral and parietal layers of the serous pericardium.

During the S-T segment, what is occurring within cardiac muscle cells? A)Sodium is rapidly diffusing out of atrial muscle cells. B)Sodium channels are beginning to open in ventricular cells and calcium is entering through slow channels in atrial cells. C)Calcium is entering and potassium is leaving ventricular cells. D)Potassium is entering atrial cells and sodium is leaving ventricular cells.

C)Calcium is entering and potassium is leaving ventricular cells.

What are the cell-to-cell contacts of the cardiac muscle fibers called? A)Z discs B)T-tubules C)Intercalated discs D)Cardiac discs E)Sarcoplasmic reticulum

C)Intercalated discs

The shutting of the semilunar valves occurs during which phase? A)Isovolumic contraction B)Ventricular ejection C)Isovolumic relaxation D)Atrial contraction and ventricular fillingE)Late ventricular diastole

C)Isovolumic relaxation

Which heart chambers containdeoxygenated blood? A)Left atrium and right atrium B)Left ventricle and right ventricle C)Right atrium and right ventricle D)Left atrium and left ventricle E)Right atrium and left ventricle

C)Right atrium and right ventricle

Which can be used to characterize blood flow in the human body? a: There is a unidirectional blood flow. b: Arteries always carry oxygenated blood. c: Veins always carry deoxygenated blood. d: Arteries carry blood away from the heart. e: Veins carry blood toward the heart. A)a, c, d, e B)a, b, c, d, e C)a, d, e D)b, c, d, e E)d, e

C)a, d, e

At the AV node of the conduction system, the action potential is A)rapidly advanced due to the cells being large and well connected by gap junctions. B)rapidly advanced due to the cells being small and well insulated by myelin. C)delayed due to the cells being small and having few gap junctions. D)delayed due to the cells being large and having many leakage channels

C)delayed due to the cells being small and having few gap junctions.

Most of the calcium that triggers contraction of cardiac muscle comes A)into the cell through leakage channels in the sarcolemma. B)into the cell through voltage-gated channels in the sarcolemma. C)from the sarcoplasmic reticulum of the cell. D)from the Golgi apparatus of the cell.

C)from the sarcoplasmic reticulum of the cell.

Occlusion ofblood vessels tends to lead to A)increases in perfusion. B)increases in capillary exchange. C)inadequate blood supply and damage to body tissues. D)defibrillation of cardic muscle cell contraction.

C)inadequate blood supply and damage to body tissues.

Pectinate muscles are found on the A)posterior wall of the right ventricle. B)anterior wall of the right ventricle. C)internal walls of the right and left atria. D)posterior walls of the right and left ventricles.E)external wall of the right atrium.

C)internal walls of the right and left atria.

The posterior interventricular sulcus A)is another name for the coronary sulcus. B)contains the great cardiac vein and coronary sinus. C)is a groove between the ventricles on the back of the heart. D)is a valve in the interventricular septum that closes at birth.

C)is a groove between the ventricles on the back of the heart.

The base of the heart faces in the _____________ directions. A)anterior and inferior B)anterior and superior C)posterior and superior D)posterior and inferior E)None of these choices is correct

C)posterior and superior

The fossa ovalis appears just above the opening of the coronary sinus within the A)left atrium. B)left ventricle. C)right atrium. D)right ventricle.

C)right atrium.

The posterior interventricular artery is a branch off of the A)superior vena cava. B)left marginal artery. C)right coronary artery. D)left coronary artery. E)coronary sinus.

C)right coronary artery.

The internal wall surface of each ventricle displays large, smooth, irregular muscular ridges called A)conus arteriosus. B)atrioventricular opening. C)trabeculae carneae. D)tendinous cords. E)pectinate muscles.

C)trabeculae carneae.

Each of the receiving chambers of the heart has awrinkled flaplike extension; the one that is more visible from an anterior view is the A) interatrial septum. B) interventricular septum. C) left auricle. D) right auricle.

D) right auricle.

Parasympathetic innervation of the heart occurs via A)CN IV. B)CN VI. C)CN VIII. D)CN X. E)CN XII.

D)CN X.

Which pair is located more anteriorly in a heart in normal position? A)Left atrium and left ventricle B)Left atrium and right ventricle C)Right atrium and left atrium D)Right atrium and right ventricle E)Right atrium and left ventricle

D)Right atrium and right ventricle

Which circuit of the cardiovascular system includes the left ventricle and aorta? A)Pulmonary circuit B)Cardio circuit C)Coronary circuit D)Systemic circuit

D)Systemic circuit

For the repolarization phase of an SA nodal cell action potential, A)sodium and potassium channels open. B)calcium channels open and sodium channels close. C)calcium and potassium channels close. D)calcium channels close and potassium channels open. E)sodium and chloride channels open.

D)calcium channels close and potassium channels open.

The atria are separated from the ventricles externally by the A)anterior interventricular sulcus. B)posterior interventricular sulcus. C)sinoventricular sulcus. D)coronary sulcus. E)None of the choices is correct

D)coronary sulcus.

Atrial contraction occurs just before A)isovolumic relaxation .B)atrial relaxation and ventricular filling. C)ventricular ejection.D)isovolumic contraction

D)isovolumic contraction

Cardiac output is usually expressed in A)beats per minute. B)mL per beat. C)mm Hg. D)liters per minute.

D)liters per minute.

A drug that decreased calcium levels in a muscle cell and thereby lowered the number of crossbridges formed during the heart's contractions would be a A)positive chronotropic agent. B)negative chronotropic agent. C)positive inotropic agent. D)negative inotropic agent.

D)negative inotropic agent.

The function of the coronary sinus is to A)connect the top and bottom halves of the heart. B)guide the aorta out of the heart. C)guide the inferior vena cava into the right atrium. D)take blood from the coronary circulation to the right atrium. E)shunt blood from the right atrium to the left atrium.

D)take blood from the coronary circulation to the right atrium.

The papillary muscles attach to the cusps of the atrioventricular valves by means of the A)pectinate muscles. B)trabeculae carneae. C)conus arteriosus. D)tendinous cords. E)tricuspid valve.

D)tendinous cords.

What part of the cardiac conduction system is located in the posterior wall of the right atrium, adjacent to the entrance of the superior vena cava? A)AV bundle B)Bundle branches C)Purkinje fibers D)AV node E)SA node

E)SA node

During ventricular contraction A)only the AV valves open. B)only the AV valves close. C)only the semilunar valves close. D)the semilunar valves close and the AV valves open. E)the semilunar valves open and the AV valves close.

E)the semilunar valves open and the AV valves close.

The resistance in arteries to the ejection of blood by the heart is known as _________.

afterload

The connections shared by arteries that allow them to shunt blood from one artery to another are called _________________.

anastomoses

This artery is sometimes referred to as the "widowmaker" because blockage of it often leads to fatal heart attack. It serves the anterior heart and is more formally called the (2 words) _________ __________ artery.

anterior interventricular

The inferior, conical end of the heart is called the _______________.

apex

The anterior part of each atrium is a flaplike extension called a(n) _______________.

auricle

The property that allows the heart to initiate each heartbeat itself is called __________________.

autorhythmicity

A chemical that alters heart rate is known as a(n) __________ agent.

chronotropic

The numerous ________________ within the intercalated discs prevent cardiac muscle fibers from pulling apart.

desmosomes

If the stroke volume is unequal between the left and right ventricles, ________ may occur, which is excess fluid surrounding or within cells.

edema

Arteries carry blood toward the heart, while veins carry blood away from the heart. t or f

f

Blood flow to the heart wall courses through coronary vessels in a steady stream. t or f

f

Cardiac reserve is greater in a nonathletic individual than in a highly trained athlete. t or f

f

The hearts nodal cells have a more negative resting potential than neurons do, because nodal cells lack leak channels for sodium and potassiumions. t or f

f

The term used to describe the inadequate blood flow to a structure caused by obstruction of the blood supply is _________________.

ischemia

The beginning of ventricular contraction, when all four valves are closed,is a phase called (2 words) __________________.

isovolumic contraction

The middle layer of the heart wall that is made of cardiac muscle tissue is the ________________.

myocardium

The time that startswhen a muscle cell is depolarized and ends when itis able to be restimulated is the __________ period

refractory

Deep to the interventricular sulci is the thick muscular wall that divides the left and right ventricles, known as the interventricular ________.

septum

The heartbeat is initiated by the cells of the _______________ node.

sinoatrial

The _______________ cardiac vein travels alongside the right marginal artery.

small

________________ innervation increases the rate and the force of heart contraction.

sympathetic

Cardiac muscle is able to use a variety of fuel types for cellular respiration.t or f

t

Immediately prior to atrial contraction, blood continues to enter the atria from the venae cavae and pulmonary veins. t or f

t

Like skeletal muscle cells, cardiac muscle cells have an absolute refractory period prior to repolarization. t or f

t

Myofibrils within cardiac muscle cells are aligned in sarcomeres. t or f

t

Nodal cells contain fast voltage-gated calcium channels. t or f

t

Parasympathetic innervation influences the heart rate, but generally tends to have no direct effect on the force of contractions. t or f

t

Preload is the stretch of the heart wall as determined by the amount of blood returned by the veins. t or f

t

SA nodal cells are autorhythmic. t or f

t

The main functions of the cardiovascular system include the transport and exchange of respiratory gases, nutrients, and wastes throughout the body. t or f

t

The pericardium helps prevent overfilling of the heart and it lessens the friction ofmovements during heartbeats. t or f

t

The receiving chambers of the heart are the atria, and the forcefully pumping chambers of the heart are the ventricles. t or f

t

The inferior chambers of the heart are called ________________.

ventricles