Help!! Biology question??

Question

The muscular walls of the ATRIA and VENTRICLES differ considerably in elasticity and thickness. Explain why their walls are different in thickness...i just posted this question, but somehow everyone didn't pick up this part - why there is a difference between the muscular walls of the atria and ventricles NOT the left ventricle from the right ventricle.

If any1 can help...that'd would be awesome! =)

Answer 1

atria and ventricles differ in thickness because atria just receive blood and pump it to ventricles which are just below.so they don't have to contract strongly and so don't need thick muscular walls.while ventricles either right or left have to pump blood to lung and aorta which are further so ventricles need to contract strongly to pump all the blood.
but what u don't know that although ventricles are thicker than atria.also left ventricle is thicker that right ventricle by 3 times more.this is because as I said right ventricle pumps blood to lungs which are closer to the heart so need moderate muscular walls.while left ventricle pumps blood to aorta then to the whole body(even till ur toes)so u have to imagine how thick the left ventricle should be to pump the blood that far...

Answer 2

The thickness depends on how much work they do. The left ventricle pushes blood around the body, the right ventricle to the lung circulation. The atria just have to push it into the ventricles. Therefore the LV muscle is thickest, then RV, then the atrial muscles.

Answer 3

ya the atria just fill with incoming blood and then it gets pushed into the ventricles when they are empty. the ventricles are much thicker because when they contract they need extreme force to push the blood back into the bloodstream.

Answer 4

cos the atria just collect blood that comes in and pushes it into the ventricles......