The general plan of human blood circulatory system:

Many scientists worked for discovering the facts about the circulation of blood in the human body. Two important scientists who revealed much knowledge of the blood circulatory system were Ibn-e-Nafees and William Harvey. Ibn-e-Nafees (1210-1286) was a physician and he is honored as the first scientist who described the pathway of blood circulation. William Harvey (1578. 1657) discovered the pumping action of the heart and the pathway of blood in major arteries and veins.