Question

What double Circulation? And what is
excretion.​

Answer 1

Double circulation in human beings allows the separation of oxygenated and deoxygenated blood in the body. It helps in maintaining a high blood pressure required for essential processes. It enables pure blood to reach the different tissues and organs of the body like kidney, liver, etc. 3.

Answer 2

Double circulation is the circulation of blood through the heart twice to complete one cardiac cycle .
Excretion is a process in which organisms put out the metabolic waste through excretory system.