The Heart

Its so easy to use

How it acts and pumps

      Your heart is a muscle. It's located a little to the left of the middle of your chest. It's about the size of your fist. Your heart lies behind your breastbone, inside your ribcage, and between your lungs. Its is about the size of your fist.

The heart beats at about 70 to 90 beats per minute. Before each beat, your heart fills with blood. When the heart muscle contracts, it squeezes to squirt the blood along. Your heart does this all day and all night, all the time. The blood provides your body with the oxygen and nutrients it needs. It also carries away waste.Your heart is a pump. The right side of your heart receives blood from the body and pumps it to the lungs. The left side of the heart does the exact opposite. It receives blood from the lungs and pumps it out to the body.

Before each beat, your heart fills with blood. Then its muscle contracts to squirt the blood along. When the heart contracts, it squeezes. Your heart does this all day and all night. It never stops while you are alive. Your hearts never stops beating while your alive.

The heart is made up of four chambers: two atria and two ventricles. The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-poor blood to the lungs. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle. The left ventricle pumps the oxygen-rich blood to the body.

Between the chambers there are valves which stop blood from flowing the wrong way. The valves open and close and help to move blood through the heart to the right place at the right time. When the valves open, blood surges into the chambers. The valves close, the heart contracts, and the blood flows out.

The blood moves through many blood vessels called arteries and veins. The blood vessels that carry blood away from the heart are called arteries. The ones that carry blood back to the heart are called veins. Blood delivers oxygen to all the body's cells. Without oxygen, these cells would die. Your arteries carry blood away from the heart.

Circulatory System -Cardiovascular System- Facts ,Functions for Kids