Deck 17: Function of the Heart

Question 1

During atrial systole,the

A) AV valves are closed.
B) ventricles are relaxed.
C) ventricles are in systole.
D) semilunar valves are open.

Answer 1

ventricles are relaxed.

Question 2

Which of the following is most likely to increase ejection fraction?

A) activation of beta1 adrenergic receptors
B) vagal discharge
C) blockade of beta1 adrenergic receptors
D) blockade of the muscarinic receptors

Answer 2

activation of beta1 adrenergic receptors

Question 3

Which of the following is most likely to relieve an anxiety-induced tachycardia?

A) vagolytic drug
B) beta1 adrenergic agonist
C) sympathomimetic
D) beta1 adrenergic blocker

Answer 3

beta1 adrenergic blocker

Question 4

Activation of the muscarinic receptors by acetylcholine

A) increases myocardial contractile force
B) causes a (+)chronotropic effect
C) increases cardiac output
D) slows heart rate

Question 5

Which term refers to the amount of blood pumped by the heart in one minute?

A) stroke volume
B) cardiac output
C) Starling's law of the heart
D) inotropic effect

Question 6

Vagal stimulation to the heart causes

A) a (+)inotropic effect.
B) heart rate to slow.
C) cardiac output to increase.
D) stroke volume to increase.

Question 7

Which of the following is the same as end diastolic volume?

A) stroke volume
B) cardiac output
C) preload
D) cardiac reserve

Question 8

Which of the following is descriptive of the vagus nerve?

A) "fight or flight"
B) parasympathetic
C) sympathetic
D) adrenergic

Question 9

What happens during ventricular diastole?

A) The ventricles are filling with blood.
B) All semilunar valves are open.
C) Both AV valves are closed.
D) Blood is pumped to the lungs and systemic circulation.

Question 10

Heart rate and stroke volume determine

A) hematocrit.
B) total blood volume.
C) cardiac output.
D) the size of the heart valves.

Question 11

A drug (i.e.,atropine)that blocks the vagus nerve

A) stops the heart.
B) increases heart rate.
C) decreases cardiac output.
D) decreases stroke volume.

Question 12

Sympathetic nerve stimulation of the myocardium

A) causes a (+)inotropic effect.
B) decreases cardiac output.
C) decreases heart rate.
D) decreases stroke volume.

Question 13

Excess vagal stimulation to the SA node is most likely to cause

A) hypertension.
B) bradycardia.
C) tachycardia.
D) anemia.

Question 14

Which of the following is responsible for the Starling effect?

A) sympathetic nerve firing
B) vagal discharge
C) activation of the beta1 adrenergic receptors
D) end diastolic volume (EDV)

Question 15

Decreased blood flow through the coronary arteries is most likely to cause

A) valve damage.
B) pulmonary edema.
C) angina pectoris.
D) bradycardia.

Question 16

What term refers to the amount of blood pumped by the ventricle in one beat?

A) cardiac output
B) blood volume
C) hematocrit
D) stroke volume

Question 17

Which of the following is most likely to increase stroke volume?

A) a (+)inotropic drug
B) a vagolytic drug
C) a (-)chronotropic drug
D) a beta1 adrenergic blocker

Question 18

Systole and diastole describe the function of the

A) pericardium.
B) SA node.
C) myocardium.
D) mediastinum.

Question 19

Which of the following is the most likely consequence of a very rapid heart rate?

A) decreased ventricular filling (with blood)
B) failure of the AV valves to open
C) failure of the SA node to fire
D) failure of the cardiac impulse to enter the His-Purkinje system

Question 20

Which of the following does not happen to a ventricle?

A) activation of the beta1 adrenergic receptors
B) discharge of sympathetic nerves
C) discharge of the vagal nerve
D) binding of norepinephrine to its receptor

Question 21

Atropine is a muscarinic antagonist and is therefore used to

A) relieve bradycardia.
B) decrease heart rate.
C) block the effects of norepinephrine.
D) increase myocardial contractile force.

Question 22

Which of the following is the most likely consequence of acute left ventricular failure?

A) jugular vein distention
B) hepatomegaly and splenomegaly
C) pulmonary edema
D) pedal edema

Question 23

Which of the following is descriptive of a drug that causes a (+)inotropic effect,a (+)dromotropic effect,and a (+)chronotropic effect?

A) vagomimetic
B) sympathomimetic
C) antimuscarinic
D) parasympatholytic

Question 24

Which of the following refers to a positive inotropic effect?

A) heart block
B) a slow heart rate
C) a rapid heartbeat
D) an increased myocardial contractile force

Question 25

Which of the following drugs is sympathomimetic?

A) beta1 adrenergic blocker
B) muscarinic agonist
C) vagolytic
D) beta1 adrenergic agonist

Question 26

A stenotic aortic valve

A) causes right ventricular hypertrophy and right-sided heart failure.
B) increases afterload,thereby increasing the work of the left ventricle.
C) causes a right-to-left shunt.
D) is a narrowing of the right semilunar valve.

Question 27

Increased return of the blood to the heart stretches the muscle,thereby

A) stimulating the sympathetic nerve.
B) activating the beta1 adrenergic receptors.
C) closing the AV valves.
D) increasing stroke volume.

Question 28

Cardiac output is determined by heart rate and

A) systemic vascular resistance.
B) stroke volume.
C) hematocrit.
D) hemoglobin concentration.

Question 29

An increased preload

A) decreases cardiac output.
B) increases stroke volume.
C) increases cardiac reserve.
D) increases afterload.

Question 30

Which of the following contains 70 ml?

A) the cardiac output
B) the volume of a ventricle
C) an average stroke volume
D) the amount of blood that flows through the pulmonary capillaries in one minute

Question 31

Sympathetic stimulation to the heart

A) decreases stroke volume.
B) increases heart rate.
C) causes bradycardia.
D) decreases cardiac output.

Question 32

What is the term that refers to an increase in stroke volume in response to the stretching of the heart?

A) Starling's law of the heart
B) a positive inotropic effect
C) heart block
D) angina pectoris

Question 33

Cardiac output

A) is determined by heart rate and pulse.
B) decreases in response to sympathetic nerve stimulation.
C) increases in response to vagal discharge.
D) is determined by heart rate and stroke volume.

Question 34

Most of the symptoms of acute left-sided heart failure are

A) relieved by morphine.
B) cured by an antibiotic.
C) respiratory in nature (e.g.,dyspnea,orthopnea).
D) confined to the lower extremities as in pedal edema.

Question 35

What is the term for the sequence of events that occur during one heartbeat?

A) stroke volume
B) cardiac output
C) cardiac cycle
D) systole

Question 36

This term refers to a heart rate of fewer than 60 beats/min.

A) bradycardia
B) heart block
C) fight-or-flight response
D) tachycardia

Question 37

An ejection fraction of 30% is

A) normal.
B) characteristic of a healthy person who is engaged in aerobic exercise.
C) characteristic of a failing heart.
D) the amount of oxygenated hemoglobin in the blood in the left ventricle.

Question 38

Increased afterload (e.g.,hypertension)

A) is usually caused by arteriolar dilation.
B) increases the work of the heart.
C) can only occur when preload increases.
D) is usually caused by intense parasympathetic (vagal)discharge.

Question 39

Which of the following most accurately describes the vagus nerve?

A) "fight or flight"
B) norepinephrine
C) parasympathetic
D) causes tachycardia

Question 40

Vagal stimulation on the heart

A) increases the force of myocardial contraction.
B) increases the amount of blood that flows into the heart from the vena cava.
C) causes tachycardia.
D) slows the heart rate.

Question 41

Digoxin,a drug used in the treatment of heart failure,increases contractile force and is therefore called a

A) diuretic.
B) (+)dromotropic agent.
C) (+)inotropic agent.
D) (+)chronotropic agent.

Question 42

Furosemide (Lasix),a potent diuretic,is administered in acute ventricular failure in order to

A) strengthen myocardial contractile force.
B) increase plasma K⁺.
C) excrete excess water and relieve the edema.
D) relieve pain.

Question 43

Milliliters/beat x beats/minute defines

A) stroke volume.
B) ejection fraction.
C) cardiac reserve.
D) cardiac output.

Question 44

An increase in venous return causes an increase in cardiac output.This is accomplished by

A) a (+)inotropic effect.
B) depolarization.
C) Starling's law of the heart.
D) a (+)chronotropic effect.

Question 45

Which of the following is an example of forward failure?

A) Blood accumulates in the pulmonary capillaries,elevating pressure and causing pulmonary edema.
B) Diminished renal blood flow stimulates the kidney to decrease urinary output and to retain Na+ and water.
C) Blood distends the jugular vein.
D) Blood distends the liver,causing hepatomegaly and digestive symptoms.