Question

The walls of ventricles are much thicker than atria. Explain.

Answer 1

The structure of heart of fishes, reptiles, birds and mammals show many structures of evolutionary significance. Thicker walls of ventricles are one of them.

Ventricles have thick walls because these are mainly involved in pumping the blood to the body parts with a certain pressure.

The walls of the left ventricle are about 3 times thicker from the right ventricle, while the atria acts as a collecting chamber for the blood which is starting to the heart thus have thin walls. Also, they have to force the blood into the ventricles that lie just below there thus atria have thin walls.