In the Normal Heart:
Video: Heart and circulatory system — How they work
Oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, and then is pumped through the pulmonary artery into the lungs where it receives oxygen.
Oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped through the aorta out to the body.
Other External Links:
Children's Heart Institute
The Heart Profilers
More CHD Facts