General

Pulmonary circulation

The right atrium of the heart receives the blood from the body. When the valve of the right atrium opens, blood flows down into the right ventricle.

The right ventricle has a muscular wall. When its muscles contract, the blood is propelled out of the heart. The blood then flows through the pulmonary or lung artery into the lungs, where it absorbs oxygen. It then flows back to the heart.

This heart-lungs-heart route is the pulmonary blood circulation.