Semilunar valve

Definition

Semilunar valves are located at the bases of the large arteries that leave the heart. They prevent blood from flowing back into the ventricles after it has been pumped out of the heart.

5 Must Know Facts For Your Next Test

1. There are two semilunar valves in the heart: the aortic valve and the pulmonary valve.
2. The aortic semilunar valve is located between the left ventricle and the aorta.
3. The pulmonary semilunar valve is located between the right ventricle and the pulmonary artery.
4. These valves open to allow blood to be ejected from the heart during ventricular contraction (systole) and close during ventricular relaxation (diastole).
5. Malfunctioning semilunar valves can lead to conditions such as aortic stenosis or pulmonary regurgitation.

Review Questions

Related terms

Atrioventricular Valves: Valves located between each atrium and ventricle that prevent backflow into atria.

Systole: The phase of the heartbeat when ventricles contract and pump blood out of the heart.

Diastole:

The phase of relaxation when ventricles fill with blood following contraction.