The ________ valve (letter A) prevents blood from flowing back into the right ventricle. It is called a semilunar valve because its cusps are shaped like a half moon.

Semilunar Valve

A type of heart valve with half-moon-shaped flaps that prevents blood from flowing back into the heart chambers after it has been ejected.

Right Ventricle

One of the four chambers of the heart, located in the lower right portion, responsible for pumping deoxygenated blood to the lungs via the pulmonary artery.

Blood Flow

The movement of blood through the circulatory system of the body, delivering oxygen and nutrients to cells and removing waste products.