Question

Double circulatory system is present in-

• A. Mammals and fishes
• B. Birds and Fishes
• C. Mammals, Birds and Fishes
• D. Mammals and Birds

Answer 1

The correct option is D Mammals and Birds

Double circulation pathways are found in mammals and birds. Double circulation allows the separation of oxygenated and deoxygenated blood in the body. Mammals and birds have four chambered hearts. The right chamber receives deoxygenated blood from the body and the right ventricles sends it to the lungs.