Question

The valve which allows blood from the ventricle into arteries are not in opposite direction are
a. The aortic valve and mitral valve
b. AV valve and semilunar valve
c. Bicuspid and tricuspid valve
d. Semilunar valve and tricuspid valve

Answer 1

Heart is composed of the right and left atria at the upper and right and left ventricle in the lower. There are four valves found in the mammalian heart. These four valves are the bicuspid valve, tricuspid valve, aortic valve, and pulmonary valve.

Complete answer:
Right atria comprise inferior and superior vena cava which allow the deoxygenated blood to enter into the left atria. From the right atrium deoxygenated blood enters into the right ventricle. From the right ventricle, blood is transported to the lungs by the pulmonary artery. The left atria of the heart comprise a pulmonary vein that carries out oxygenated blood from the lung into the left atria. Left atria transfer the blood into the left ventricle. From the left ventricle blood supplies to the body by the aorta.

The bicuspid valve is composed of 2 cups and is located between the left atrium and left ventricle. It allows the flow of blood from the left atria to the left ventricle and prevents the backward flow of blood from the left ventricle to the left atria. The tricuspid valve (comprises 3 cups)is located between the right atria and right ventricle which prevents the blood from flowing from the right ventricle to the right atria.

Pulmonary semilunar valve or pulmonary valve is found between the right ventricle and the pulmonary trunk. Blood can’t return to the right ventricle from the pulmonary trunk due to the pulmonary trunk. The aortic semilunar valve restricts the blood flow from the aorta to the left ventricle.

Hence, the correct answer is option (B).

Note: Heart valves are responsible for flowing the blood only in one direction. The endocardium lines the heart valves as well as the chambers. Bicuspid and tricuspid valves are known as the Atrioventricular valve or AV valve and a pulmonary valve and aortic valve are known as the semilunar valve.