Why is the heart considered two pumps?

Answer 1

The heart of mammals (and birds) is completely divided into two sides, left and right. Blood cannot pass directly from one side to the other, but has to leave the heart first. For example, blood from the right side goes first to the lungs before returning to the left side of the heart. Blood from the left side goes round the body before returning to the right side. Blood passing through the right side of the heart is deoxygenated ie it has had oxygen removed as it circulated through the body. Blood passing through the left side of the heart is oxygenated, as it has collected oxygen in the lungs before returning to the heart. So, each side of the heart works as a separate pump, one side pumping deoxygenated blood and the other pumping oxygenated blood. Because the two pumps are physically connected to form one organ, the heart is called a double pump. In the embryo, the heart begins as two separate tubes lying side by side which then fuse together. See: http://www.bbc.co.uk/science/humanbody/body/factfiles/heart/heart.shtml

Answer 2

First heart sound ("lubb"): Sounds associated with closing of the atrioventricular valves (tricuspid and

bicuspid) valves.

• Second heart sound ("dupp"): Sounds associated with closing of the semilunar valves (aortic and

pulmonary).

Answer 3

its considered a two pumps because it produces blood to your left and the other pump to your right- im an eleven year old so dont be that reliable on me...