Your heart’s job is to pump blood rich in oxygen and nutrients to all parts of your body. The figure below shows how this happens.
The Four Pumping Chambers of the Heart
Veins return oxygen-poor blood from the body to the right atrium of the heart. From there, the blood enters the right ventricle, which pumps the blood to the lungs to get a fresh supply of oxygen.
When oxygen-rich blood returns to the heart from the lungs, it is received by the left atrium. It then enters the left ventricle, which pumps the blood out to all parts of the body.
Your Hardworking Heart
Your heart is a hard-working muscle. On average, it beats 60-100 times each minute, every day of your life. Each beat pumps blood to all parts of your body. By the time you’re 70 years old, your heart will have pumped almost 50 million gallons of blood - quite a feat for an organ about the size of your fist!