THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -Blood enters the right atrium and passes through the right ventricle. The right ventricle pumps the blood to the lungs where it becomes oxygenated. The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium.

Detailed explanation-2: -The right atrium receives deoxygenated blood from systemic circulation and the left atrium receives oxygenated blood from pulmonary circulation.

Detailed explanation-3: -The inferior and superior vena cava bring oxygen-poor blood from the body into the right atrium. The pulmonary artery carries oxygen-poor blood from the right ventricle into the lungs, where oxygen enters the bloodstream.