Question 1

Which of the following best describes the function of the pulmonary circuit in the cardiovascular system?

Accepted Answer

It carries oxygen-poor blood from the right ventricle to the lungs for gas exchange.

Question 2

The pericardial cavity is important because it:

Accepted Answer

Contains serous fluid that reduces friction between the heart and pericardial layers.

Question 3

Which layer of the heart wall is responsible for the heart’s contractile force?

Accepted Answer

Myocardium

Question 4

A patient has a blockage in the left coronary artery. Which area of the heart is most likely to be affected?

Accepted Answer

The left ventricle and interventricular septum

Question 5

Which of the following statements about the atrioventricular (AV) valves is correct?

Accepted Answer

They are anchored by chordae tendineae to papillary muscles.

Question 6

During which phase of the cardiac cycle does the ventricular pressure exceed atrial pressure, causing the AV valves to close?

Accepted Answer

Isovolumetric contraction phase

Question 7

Which of the following equations correctly calculates cardiac output (CO)?

Accepted Answer

$$CO = HR 	imes SV$$

Question 8

If a patient’s end diastolic volume (EDV) is 130 ml and end systolic volume (ESV) is 60 ml, what is their stroke volume (SV)?

Accepted Answer

$$SV = 130\,ml - 60\,ml = 70\,ml$$

Question 9

Which of the following best explains why the left ventricle has a thicker wall than the right ventricle?

Accepted Answer

It must generate more force to pump blood through the systemic circuit.

Question 10

Which event is represented by the QRS complex on an electrocardiogram (ECG)?

Accepted Answer

Ventricular depolarization

Question 11

A patient is experiencing bradycardia. Which of the following best describes their condition?

Accepted Answer

Resting heart rate below 60 beats/min

Question 12

Which of the following is a direct effect of increased sympathetic stimulation on the heart?

Accepted Answer

Increased heart rate and contractility

Question 13

Which of the following best describes the role of gap junctions in cardiac muscle?

Accepted Answer

They electrically connect cardiac muscle cells, allowing coordinated contraction.

Question 14

Which sequence correctly traces the path of an action potential through the intrinsic conduction system of the heart?

Accepted Answer

SA node → AV node → AV bundle → bundle branches → Purkinje fibers

Question 15

A patient with persistent high blood pressure is at risk for heart failure primarily because:

Accepted Answer

High blood pressure increases afterload, making it harder for the ventricles to eject blood.

Question 16

Which of the following is true regarding the heart sounds 'lub-dup'?

Accepted Answer

The 'lub' is caused by the closing of the AV valves; the 'dup' is caused by the closing of the SL valves.

Question 17

Which of the following would most likely result from a blockage in the coronary arteries?

Accepted Answer

Myocardial infarction (heart attack)

Question 18

If the vagus nerve to the heart were cut, what would happen to the heart rate?

Accepted Answer

It would increase to about 100 beats/min, the intrinsic rate of the SA node.

Question 19

Which of the following best describes the effect of increased venous return on stroke volume?

Accepted Answer

It increases preload and increases stroke volume.

Question 20

Which of the following is the correct formula for stroke volume (SV)?

Accepted Answer

$$SV = EDV - ESV$$

The Cardiovascular System: The Heart – Structure, Function, and Physiology

Study Guide - Practice Questions