I am not sure, but i think they empty into the chambers.
the atriventriculart node causes both atria to contract
Those are the veins that drain blood from the lungs, and empty into the left atria.
They both contract at the same time.
The Sinoatrial Node sends a wave of electric impulses through the heart, which causes both atria to contract.
Contraction of both atria
SA node sends an impulse for the atria to contract. AV node is then activated which contracts the ventricles.
The atria contract simultaneously to push blood into the ventricles. This coordinated contraction ensures efficient filling of the ventricles with blood before they contract to pump blood out to the rest of the body.
The are extentions of the Atria.
the atria
both the right and left atria receive blood.
The atria are a part of your heart which is in the circulatory system
The upper portion of your heart contains the atria, both right and left.