Passing of blood through the heart twice during a cardiac cycle is known as double circulation. Once, the deoxygenated blood passes through the right side of heart and the oxygenated blood passes through the left side. So, deoxygenated blood is totally separated from oxygenated blood. Benefit of this is that it is highly efficient method of blood circulation.
Final Answer:-
Animals that show double circulation are more active, more energetic and are warm blooded animals. Double circulation is present in mammals and bird
