Cardiac Function: Interactive Learning Quizzes for Physiology Students

Question 1

What is the function of the sinoatrial node?

Accepted Answer

Generate electrical impulses

Answer

Relay electrical impulses

Answer

Control heart rate

Answer

Regulate blood pressure

Question 2

Which of the following is NOT a role of the heart valves?

Accepted Answer

Control heart rate

Answer

Prevent backflow of blood

Answer

Regulate blood pressure

Answer

Maintain unidirectional blood flow

Question 3

What is the Starling's Law of the Heart?

Accepted Answer

The force of contraction is directly proportional to the end-diastolic volume.

Answer

The heart rate is inversely proportional to the stroke volume.

Answer

The cardiac output is directly proportional to the systemic vascular resistance.

Answer

The blood pressure is directly proportional to the heart rate.

Question 4

Uncover the energy demands of the heart. Explain the metabolic pathways essential for ATP production and their relative contributions.

Accepted Answer

Fatty acid oxidation is the primary energy source for the heart, with lactate and glucose playing supporting roles.

Answer

The heart's energy needs are low, relying solely on glucose oxidation for ATP production.

Answer

Ketones cannot be utilized as an energy source by the heart.

Answer

Anaerobic glycolysis is the main ATP-generating pathway in the heart at rest.

Question 5

Define cardiac failure, outlining its pathophysiology and consequences, including its impact on organ perfusion and overall health.

Accepted Answer

Cardiac failure occurs when the heart cannot pump enough blood to meet the body's needs, leading to inadequate organ perfusion and reduced oxygen delivery to tissues.

Answer

Cardiac failure only affects the heart and has no impact on other organs or overall health.

Answer

Cardiac failure is solely caused by sudden cardiac events like heart attacks or arrhythmias.

Answer

The effects of cardiac failure are limited to shortness of breath and fatigue.

Question 6

Which phase is NOT part of the cardiac cycle?

Accepted Answer

Plateau

Answer

Systole

Answer

Diastole

Answer

Isovolumetric relaxation

Question 7

What is the impact of increased vagal tone on heart rate?

Accepted Answer

Decreases heart rate

Answer

Increases heart rate

Answer

Has no effect on heart rate

Question 8

Which of the following accurately depicts the sequence of cardiac events during systole?

Accepted Answer

Atrial depolarization, ventricular depolarization, ventricular contraction, atrial repolarization

Answer

Atrial depolarization, ventricular contraction, ventricular repolarization, atrial repolarization

Answer

Ventricular depolarization, atrial depolarization, ventricular contraction, atrial repolarization

Question 9

Which of the following factors is known to increase heart rate?

Accepted Answer

Sympathetic stimulation

Answer

Hypothermia

Answer

Increased venous return

Answer

Parasympathetic stimulation

Question 10

What is the primary determinant of cardiac output?

Accepted Answer

Stroke volume multiplied by heart rate

Answer

Central venous pressure multiplied by pulmonary vascular resistance

Answer

Mean arterial pressure multiplied by systemic vascular resistance

Answer

End-diastolic volume multiplied by ejection fraction

Question 11

Which of the following is considered a compensatory mechanism for heart failure?

Accepted Answer

Increased renin-angiotensin-aldosterone system activity

Answer

Decreased sympathetic tone

Answer

Reduced ejection fraction

Question 12

Which component of the heart is responsible for initiating the heartbeat?

Accepted Answer

Sinoatrial node

Answer

Atrioventricular node

Answer

Purkinje fibers

Answer

Bundle of His

Question 13

How does increased preload affect the Frank-Starling curve?

Accepted Answer

It shifts the curve up and to the right

Answer

It shifts the curve down and to the left

Answer

It has no effect on the curve

Question 14

Which of the following is a known risk factor for coronary artery disease?

Accepted Answer

Hypertension

Answer

Bradycardia

Answer

Increased heart rate

Answer

Reduced ejection fraction

Question 15

During the cardiac cycle, the ventricular contraction phase in which blood is ejected from the ventricles into the arteries is called:

Accepted Answer

Systole

Answer

Reperfusion

Answer

Ischemia

Answer

Diastole

Question 16

The electrical impulse that triggers the cardiac cycle originates from the:

Accepted Answer

Sinoatrial node (SA node)

Answer

Atrioventricular node (AV node)

Answer

Purkinje fibers

Answer

Bundle of His

Question 17

Cardiac output is calculated as the product of which two factors?

Accepted Answer

Heart rate and stroke volume

Answer

Blood pressure and peripheral resistance

Answer

Venous return and preload

Answer

Inotropy and lusitropy

Question 18

The electrical event corresponding to the depolarization of the atrial myocardium is the:

Accepted Answer

P wave

Answer

T wave

Answer

QRS complex

Answer

U wave

Question 19

Which of the following measurements reflects the pressure generated by the contracting left ventricle?

Accepted Answer

Systolic blood pressure

Answer

Diastolic blood pressure

Answer

Mean arterial pressure

Answer

Pulmonary artery pressure

Question 20

The Starling curve describes the relationship between:

Accepted Answer

Ventricular preload and stroke volume

Answer

Afterload and myocardial contractility

Answer

Cardiac output and systemic vascular resistance

Answer

Heart rate and cardiac output

Question 21

Which branch of the autonomic nervous system increases heart rate and myocardial contractility?

Accepted Answer

Sympathetic

Answer

Somatic

Answer

Enteric

Answer

Parasympathetic

Question 22

The measurement of blood flow through the heart's coronary arteries is known as:

Accepted Answer

Coronary angiography

Answer

Echocardiography

Answer

Magnetic resonance imaging (MRI)

Answer

Electrocardiography

Question 23

Which of the following medications is commonly used to treat heart failure by reducing preload and afterload?

Accepted Answer

Enalapril

Answer

Aspirin

Answer

Amiodarone