Question

describe the double circulation in human being ? why is it neccesary ​

Answer 1

During a single cycle blood goes twice in the heart which is known as double circulation. It is necessary in human being to separate oxygenated and de-oxygenated blood because this makes their circulatory system is more efficient and helps in maintaining constant body temperature.

Answer 2

in the double circulation blood is passed twice from heart in one complete cycle