Question

Write 3 paragraphs describing the valves in the heart, and name all 4 valves and where blood flows coming into and out of each valve.

Answer 1

The heart has 4 valves namely mitral or bicuspid valve, tricuspid valve, aortic valve and pulmonary valve.

The heart valves are made up of flaps called as leaflets or cusps. The leaflets are flap like structures which are thin, bu strong. Also these flap of tissues of heart valves are supported by a ring of tough and fibrous tissues called as annulus which maintains the shape of the valves at their position. It is to be noted that, the bicuspid or mitral valve has two flaps of tissues or two leaflets only, while the other 3 valves has three flap of tissues or 3 leaf lets.

Mitral valve :

It is also called as bicuspid valve and are present between the left auricle and left ventricle. When the left auricle contracts, the bicuspid valve opens by the pressure of auricular blood of left auricle allowing the blood to flow to the left ventricle. In the next phase, when the left auricle gets relax and the left ventricle contracts, the bicuspid valve closes preventing the back flow of blood from the left ventricle to the left auricle.

Tricuspid valve :

This valve is present between the right auricle and right ventricle. When the right auricle contracts this valve opens by the pressure of right auricular blood allowing the flow of blood from right auricle to right ventricle. When the right ventricle contracts, the tricuspid valve closes preventing the back flow of blood from the right ventricle to the right auricle.

Pulmonary valve :

This valve is present between the right auricle and pulmonary artery. When the right ventricle contracts, the pulmonary valve opens allowing the flow of blood into the pulmonary artery which carries the deoxygenated blood from right ventricle to the lungs. When the right ventricle relax, the pulmonary valve closes preventing the back flow of blood from the pulmonary artery to the right ventricle.

Aortic valve :

This valve is present between the aorta and the left ventricle. On contraction of the left ventricle, this valve opens allowing the flow of oxygenated blood to the aorta from the left ventricle. Than the aorta branches to form many arteries and supplies blood to whole body. But when the left ventricle relax, the aortic valve closes preventing the back flow of blood into left ventricle from the aorta.