The heart is a huge organ of muscle. The function of the heart is to pump the blood through the body. The heart is made up of four chambers, but has two hard working pumps; one is to force blood to the lungs and the other to force blood to the rest of the body.
Each person’s body contains about 4.7 liters of blood. The function of blood is to help carry food and oxygen and the other is to protect us from germs. The tubes that receive blood from the body are called veins. The blood in the veins is dark read because it is full of oxygen. The white cells act to protect the body from invading germs. The blood receives oxygen from the lungs.