Question

what is atria???define??

Answer 1

i believe you're referring to one of the chambers in the heart. there are 4 chambers total. 2 atria and 2 ventricles.

the atria receive blood from either the lungs or the body and pumps it into the ventricles. the ventricles pump the blood out to the lungs or the body.

Answer 2

no actually atria i the cnecction link b/w atrium and ventricle beacuse at the time of contraction heart dont moves dese fibres move

Answer 3

No, that is not correct. Atria is the plural form for the word atrium. There are valves that "link" the atria to the ventricles : the tricuspid valve and the mitral valve.

The heart is a muscle activated by nodes. Nodes conduct electricity within the heart. Activity in these nodes causes the heart to contract.

This link explains the cardiac cycle:
http://en.wikipedia.org/wiki/Cardiac_cycle