Write briefly about the work done by William Harvey on circulation of blood.
A. 1) William Harvey was an Englishman who after became a doctor went to Italy for further education.
2) Harvey dissected the hearts of dead people and studied the valves between each atrium and its ventricle.
3) Harvey noticed that they were one way valves which allow blood to flow from atrium to the ventricle, but not from ventricle into the atrium.
4) He also noticed that all the veins in the human body allows blood to flow towards heart.
5) Harvey also identified that the blood flows through the heart twice in human beings.
Hence it is called double circulation. .
6) Harvey also showed that it was impossible to suppose that the blood was used up in the body and that new blood was formed
7) He found that in one hour, the heart pumped out a quantity of blood that was three times the weight of a man.
8) The same blood had to circulate and be used over and over again.