Question

Valves are present in:

• A. Atria , veins and ventricles
• B. Pacemaker, veins and arteries
• C. All of the above
• D. SA node. AV node and arteries

Answer 1

The correct option is A Atria , veins and ventricles

Valves present in the heart and veins prevent the backflow of blood, that is, flow of blood in the direction opposite to that in which it is flowing.

The heart has four valves - one for each chamber of the heart. They are: Aortic valve, pulmonary valve, mitral valve and tricuspid valve.

The valves keep blood moving through the heart in the right direction.
The mitral valve and tricuspid valve are located between the atria (upper heart chambers) and the ventricles (lower heart chambers). The aortic valves are located between the left ventricle and the aorta. The pulmonary valve or the pulmonic valve lies between the right ventricle and pulmonary artery.

• Veins have valves as small crescent-shaped flaps of tissue, that help prevent a backflow of blood.