Heart Valves Overview

What is the primary function of the heart valves?

Which valves are categorized as atrioventricular valves?

What happens when the ventricles are relaxed?

What occurs when the ventricles contract?

How do the semilunar valves prevent backflow of blood into the ventricles?

What triggers the closing of the AV valves during the cardiac cycle?

What mechanism prevents the AV valves from everting during ventricular contraction?

What material mainly composes the structure of the heart valves?

Heart Valves

Heart valves are structures ensuring one-way blood flow. They're made of connective tissue and endocardium (inner heart layer).
Four main valves: two atrioventricular (AV) valves and two semilunar valves.

Atrioventricular Valves

AV valves (tricuspid and mitral/bicuspid) connect atria to ventricles.
Tricuspid valve is between the right atrium and right ventricle.
Mitral/bicuspid valve is between the left atrium and left ventricle.
When ventricles relax, cusps are open, allowing blood flow from atria to ventricles.
When ventricles contract, pressure forces cusps to close, preventing backflow to atria. This is aided by chordae tendineae and papillary muscles that prevent the cusps from inverting. Damage to these structures can cause regurgitation.

Semilunar Valves

Semilunar valves (pulmonary and aortic) control blood flow from ventricles into arteries.
Pulmonary valve is between the right ventricle and pulmonary artery.
Aortic valve is between the left ventricle and aorta.
When ventricles contract, pressure forces cusps open to allow blood into arteries.
Relaxation causes backflow to close the valves.
Crescent-shaped cusps, with each attaching to arterial wall.

Explore the functions and structures of heart valves in this quiz. Understand the differences between atrioventricular and semilunar valves, their roles in blood flow, and the mechanisms that prevent backflow. Test your knowledge on the anatomy of the heart.