Question

What is double circulation? Explain.

Answer 1

• In double circulation, blood passes twice through the heart making one complete round through the body. De-oxygenated blood comes from the body to the right atrium, as it expands. Then it contracts to transfer the blood to the right ventricle causing it to dilate. (1.5 Mark)
• The right ventricle, in turn, pumps it to the lungs for oxygenation. From the lungs, oxygenated blood is brought back to the left side chambers of the heart by pulmonary vein which is pumped to rest of the body by aorta. (1.5 Mark)