Map of the Human Heart
Originally appeared on the NOVA Web site Cut to the Heart.
Let's get straight to the heart of the matter—the heart's job is to move
Day and night, the muscles of your heart contract and relax to pump blood
throughout your body. When blood returns to the heart, it follows a complicated
pathway. If you were in the bloodstream, you would follow the
steps below one by one.
Oxygen-poor blood (shown in blue) flows from the body into the right
Blood flows through the right atrium into the right ventricle.
The right ventricle pumps the blood to the lungs, where the blood releases
waste gases and picks up oxygen.
The newly oxygen-rich blood (shown in red) returns to the heart and enters
the left atrium.
Blood flows through the left atrium into the left ventricle.
The left ventricle pumps the oxygen-rich blood to all parts of the body.