Question

Valves which allow blood from ventricles into arteries and not in opposite direction are

• A. Aortic valve and mitral valve
• B. AV valves and semilunar valves
• C. Bicuspid and tricuspid valves
• D. Semilunar valves and tricuspid valves

Answer 1

Answer: (B)

AV valves and semilunar valves

• AV or atrioventricular valves are present between atria and ventricles. These include tricuspid and bicuspid valves.

1. Tricuspid valve is present between right atrium and right ventricle. It prevents the backflow of blood from right ventricle into right atrium during ventricular contraction.
2. Bicuspid valve is also known as mitral valve. It is present between left atrium and left ventricle. It prevents the backflow of blood from left ventricle into left atrium during ventricular contraction.

• Semilunar valves are paired, one of which is present at the base of aorta and the other is present at the base of pulmonary artery. These valves prevent the backflow of blood from aorta and pulmonary artery into left ventricle and right ventricle respectively.

So, the correct answer is 'AV valves and semilunar valves'.