How is a four-chambered heart more efficient than a two or three chambered heart?

Answer 1

The oxygenated blood from the lungs going to the body is kept separate from the non-oxygenated blood from the body going to the lungs in the separate ventricles of the 4 chambered heart while the oxygenated and non-oxygenated blood are mixed in the single ventricle of the 3 or 2 chambered heart thus diluting the oxygen in the blood going to the body.

Answer 2

In four-chambered heart there is complete separation of oxygenated and deooxygenated blood. Two- chambered heart pumps only deoxygenated blood.In three- chambered heart, there is a possibility of both oxygenated and deoxygenated blood getting mixed in the ventricle.In the four -chambered heart the left side has pure blood and the right side has impure blood.The blood from the right ventricle goes to the lungs, while the blood from the the left ventricle goes to the whole body.Crocodiles, brids and mammals have four-chambered heart.

Answer 3

It keeps the oxygenated blood separate from the deoxygenated blood. A three chambered heart has one ventricle where both oxygenated blood and deoxygentated blood enter and sometimes mix with one another. This mixing is inefficient because the body is not getting the maximum amount of oxygen this way.

There is much more I could tell you about the pathway the blood travels, but I believe that is enough to answer your question.

Answer 4

a 4 chamber heart has two chambers for the heart to lung circulation and two for the heart to body circulation.
A crocodile has 3 chambers where the 2 circulations partly mix, reducing the efficiency.
Having 2 chambers in a row provides a higher bloodpressure, than a single chamber can manage

Answer 5

Because God made it that way. Or are you needing a more "scientific" answer. My answer above is the best one. God Bless you.