Question

45/59
which chamber of the heart does old blood from
the body first enter?
right atrium right ventricle
left atrium left ventricle

Explanation:

The circulatory system's basic pathway: de - oxygenated (old) blood from the body returns via the vena cava. The vena cava empties into the right atrium. This is the first chamber of the heart that old blood from the body enters. The right ventricle then pumps this blood to the lungs for oxygenation. The left atrium receives oxygenated blood from the lungs, and the left ventricle pumps it out to the body.

Answer:

Right Atrium