$$CO = 80 \times 70 = 5600\ \text{mL/min}$$

Question 1

Which layer of the heart is responsible for the muscular contractions that pump blood throughout the body?

Accepted Answer

Myocardium

Question 2

What is the main function of the intercalated discs found in cardiac muscle tissue?

Accepted Answer

To allow rapid transmission of electrical signals and strong mechanical connection between cells

Question 3

Which of the following correctly describes the flow of blood through the heart starting from the vena cava?

Accepted Answer

Right atrium → Right ventricle → Pulmonary artery → Lungs → Left atrium → Left ventricle → Aorta

Question 4

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

Accepted Answer

Tricuspid valve

Question 5

During which phase of the cardiac cycle are all heart valves closed?

Accepted Answer

Isovolumetric contraction

Question 6

What is the formula for cardiac output ($$CO$$)?

Accepted Answer

$$CO = HR 	imes SV$$

Question 7

Which of the following best describes the role of the sinoatrial (SA) node?

Accepted Answer

It initiates the electrical impulses that set the pace for the heart rate

Question 8

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

Accepted Answer

Left ventricle and interventricular septum

Question 9

Which of the following events occurs during the QRS complex of an ECG?

Accepted Answer

Ventricular depolarization

Question 10

Which of the following is NOT a function of the pericardium?

Accepted Answer

Generating electrical impulses for heart contraction

Question 11

If a patient’s heart rate is 80 beats per minute and their stroke volume is 70 mL, what is their cardiac output?

Accepted Answer

$$CO = 80 	imes 70 = 5600\ 	ext{mL/min}$$

Question 12

Which of the following best explains why the heart requires its own circulation (coronary circulation)?

Accepted Answer

Because the myocardium is too thick for nutrients to diffuse from the blood inside the heart chambers

Question 13

Which of the following structures is responsible for delaying the electrical signal before it reaches the ventricles?

Accepted Answer

Atrioventricular (AV) node

Question 14

Which of the following correctly matches the heart valve with its function?

Accepted Answer

Aortic valve: prevents backflow into the left ventricle

Question 15

Which phase of the cardiac cycle is associated with the first heart sound ($$S_1$$)?

Accepted Answer

Isovolumetric contraction

Question 16

Which of the following factors would increase stroke volume?

Accepted Answer

Increased contractility of cardiac muscle

Question 17

Which neurotransmitter is released by the parasympathetic nervous system to decrease heart rate?

Accepted Answer

Acetylcholine

Question 18

Which of the following best describes the plateau phase of the cardiac muscle action potential?

Accepted Answer

Influx of Ca$$^{2+}$$ ions maintains depolarization

Question 19

Which structure in the cardiac conduction system is responsible for distributing the electrical signal throughout the ventricles?

Accepted Answer

Purkinje fibers

Question 20

A patient’s ECG shows a prolonged PR interval. Which part of the cardiac conduction system is most likely affected?

Accepted Answer

AV node

Heart Anatomy, Cardiac Muscle, and Cardiac Physiology Study Guide

Study Guide - Practice Questions