$$CO = Stroke\ Volume \times Heart\ Rate$$

Question 1

Which layer of the heart is primarily responsible for its contractile function?

Accepted Answer

Myocardium

Question 2

Which valve prevents backflow of blood from the right ventricle into the right atrium?

Accepted Answer

Tricuspid valve

Question 3

During which phase of the cardiac cycle do the ventricles contract to pump blood out of the heart?

Accepted Answer

Systole

Question 4

Which structure initiates the electrical impulse that triggers the heartbeat?

Accepted Answer

Sinoatrial (SA) node

Question 5

What is the main function of the coronary circulation?

Accepted Answer

To deliver oxygen and nutrients to the heart muscle itself

Question 6

Which of the following best describes the role of intercalated discs in cardiac muscle?

Accepted Answer

They connect cardiac muscle cells and allow rapid electrical communication

Question 7

A blockage in which artery is most likely to cause a myocardial infarction?

Accepted Answer

Coronary artery

Question 8

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

Accepted Answer

Ventricular depolarization

Question 9

Which formula correctly calculates cardiac output ($$CO$$)?

Accepted Answer

$$CO = Stroke\ Volume 	imes Heart\ Rate$$

Question 10

Which of the following is NOT a common cause of congestive heart failure?

Accepted Answer

Low blood glucose

Question 11

Which heart sound ('lub-dub') is caused by the closure of the AV valves?

Accepted Answer

First heart sound (S1)

Question 12

Which of the following best describes bradycardia?

Accepted Answer

A slow heart rate below 60 beats per minute

Question 13

Which of the following statements about cardiac muscle is TRUE?

Accepted Answer

Cardiac muscle cells are branched and connected by intercalated discs

Question 14

Which valve is located between the left atrium and left ventricle?

Accepted Answer

Mitral (bicuspid) valve

Question 15

What is the primary function of the aorta?

Accepted Answer

To supply oxygenated blood to the body

Question 16

Which phase of the cardiac cycle is associated with ventricular relaxation and filling?

Accepted Answer

Diastole

Question 17

Which of the following is a direct effect of ventricular depolarization?

Accepted Answer

Ventricles contract

Question 18

Which of the following best explains why the heart rate increases during exercise?

Accepted Answer

To increase oxygen delivery to tissues

Question 19

Which of the following is the correct sequence for the electrical conduction pathway in the heart?

Accepted Answer

SA node → AV node → Bundle of His → Purkinje fibers

Question 20

Which of the following is a function of chemoreceptors in the cardiovascular system?

Accepted Answer

Detect changes in blood oxygen, carbon dioxide, and pH levels

Study Guide: The Cardiovascular System – The Heart

Study Guide - Practice Questions