Question

describe double circulation in human beings. why is it necessary?

answer :
during a single cycle blood goes twice in the heart which is known as double circulation ​

Answer 1

Answer:

double circulation is seen in mammals and aves.

Explanation:

double circulation consist of 1) Systemic circulation and 2) Pulmonary circulation

★ In pulmonary circulation the blood purification takes place and in Systemic circulation the purified blood is send throughout body to replenish tissue.

so ; Double circulation is necessary in human beings.