General

Systemic circulation

The oxygen-rich blood from the lungs enters the left atrium of the heart. When the valve of the left atrium opens, the blood flows down into the left ventricle. The wall of this heart chamber is even more muscular than that of the right ventricle. As these muscles contract, the blood is propelled through the rest of the body.

The blood flows via the aorta and the arteries to all organs and all cells of the body. It delivers its oxygen to them. The oxygen-depleted blood then flows back to the heart.

This heart-body-heart route is the systemic blood circulation.