In mammals, why are there 4 chambers to the heart?

Question

hey, In mammals, why are there 4 chambers to the heart? any help appreciated!

Answer 1

What the 4 chambers do:

Right atrium loads in body's venous blood.

Right ventricle sends blood to lungs.

Left atrium loads in lungs' blood.

Left ventricle sends blood to the body.

How did they get that way?

(a) Evolution:  Something with a simpler heart mutated in such a way as to have this type of heart, and didn't have something half-way, which would have killed it.

(b) Creationist:  Evolution is designed.

(c) Strict creationist: Poof.

Answer 2

Can't answer "why," sorry.  I can only tell you that the double circulation, separating oxygen-depleted blood from oxygenated, is more efficient for active warm-blooded creatures than the previous "reptilian" three chambered system that mixed oxygenated and depleted blood.

Answer 3

Hi  =]

The heart has four chambers. The two ventricles (right and left) are muscular chambers that propel the blood out of the heart (the right ventricle to the lungs, and the left ventricle to all other organs). The two atria (right and left) hold the blood returning to the heart, and at just the right moment empty into the right and left ventricles.

Basically they all have their own task to do and job whether it is to the lungs or away from the heart.

Hope this helped =)

Roah