$$CO = HR \times SV$$; $$HR is $$heart rate, $$SV is $$stroke volume

Question 1

Which layer of the heart is responsible for the actual contraction of cardiac muscle, and what is its primary function?

Accepted Answer

Myocardium; generates the force needed to pump blood

Question 2

A patient presents with fluid accumulation in the pericardial cavity. Which condition is most likely, and what is the physiological consequence?

Accepted Answer

Pericarditis; restricted heart movement and reduced cardiac output

Question 3

Which of the following correctly describes the pathway of blood through the heart, starting from the right atrium?

Accepted Answer

Right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary trunk → lungs

Question 4

Which equation correctly represents cardiac output ($$CO$$), and what does each variable stand for?

Accepted Answer

$$CO = HR 	imes SV$$; $$HR is $$heart rate, $$SV is $$stroke volume

Question 5

During ventricular systole, which valves are open and which are closed?

Accepted Answer

Atrioventricular valves are closed; semilunar valves are open

Question 6

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

Accepted Answer

Tricuspid valve

Question 7

A blockage in the left coronary artery would most directly affect which region of the heart?

Accepted Answer

Left atrium and left ventricle

Question 8

Which of the following best explains the Frank-Starling law of the heart?

Accepted Answer

The greater the stretch of cardiac muscle fibers, the stronger the contraction

Question 9

Which component of the heart's conduction system is responsible for setting the pace of the heartbeat?

Accepted Answer

Sinoatrial (SA) node

Question 10

If the foramen ovale fails to close after birth, what is the most likely consequence?

Accepted Answer

Decreased oxygenation of systemic blood due to mixing of oxygenated and deoxygenated blood

Question 11

Which of the following is a function of the fibrous skeleton of the heart?

Accepted Answer

Provides structural support and anchors heart valves

Question 12

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

Accepted Answer

Ventricular depolarization

Question 13

Which of the following best describes the role of chordae tendineae?

Accepted Answer

Anchor the atrioventricular valves to papillary muscles, preventing valve prolapse

Question 14

Which equation correctly calculates stroke volume ($$SV$$)?

Accepted Answer

$$SV = EDV - ESV$$; $$EDV is $$end-diastolic volume, $$ESV is $$end-systolic volume

Question 15

Which of the following would most likely increase cardiac output ($$CO$$)?

Accepted Answer

Increased heart rate and increased stroke volume

Question 16

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

Accepted Answer

Increased heart rate and increased contractility

Question 17

Which valve prevents backflow of blood from the aorta into the left ventricle?

Accepted Answer

Aortic semilunar valve

Question 18

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

Accepted Answer

Allow rapid transmission of electrical impulses between cardiac cells

Question 19

A patient with damage to the bundle of His would most likely experience which of the following?

Accepted Answer

Impaired conduction between the atria and ventricles

Question 20

Which of the following is true regarding the pulmonary and systemic circulations?

Accepted Answer

Pulmonary circulation carries deoxygenated blood from the right ventricle to the lungs

The Cardiovascular System: The Heart – Study Notes

Study Guide - Practice Questions