Question

explain the double circulation of heart

Answer 1

double circulation means for only single unit of purification blood flows twice into the heart for purification ,first from arteries and veins and then from pulmonary artery and vein.

Answer 2

The majority of mammals (including humans) utilize a double circulatory system. This means we have two loops in our body in which blood circulates. One is oxygenated, meaning oxygen rich, and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.
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