Question

What is circulatory system? Describe the circulatory system of humans.

Answer 1

Circulatory system: It is a system of organs that takes part in the flow of materials in the body of an organism inside an extracellular fluid.
Circulatory system in humans:
(a) The right atrium receives deoxygenated blood from all the parts of the body through large veins called vena cava.
(b) When the right atrium is full of blood, it contracts and the blood is forced into right ventricle.
(c) When the right ventricle is full of blood, it contracts and the blood is pumped into the pulmonary trunk.
(d) From right ventricle, the pulmonary artery carries the blood to the lungs for oxygenation.
(e) The oxygenated blood returns to the heart via pulmonary veins that empty into the left auricle.
(f) When the left auricle contracts, the blood passes into the left ventricle by the opening of bicuspid valve.
(g) On contraction of the left ventricle, the blood is pumped into the artery called aorta.
(h) The aorta branches into vessels which transports blood to the heart and all the body parts.