• The heart is the pump of the circulatory system.
• It is made of cardiac muscle which does not tire.
• Cardiac muscle receives its own blood supply through the coronary arteries and veins.
• The septum divides the heart into right and left sides.
• The heart has four chambers; right atrium, right ventricle, left atrium, left ventricle.

Blood Flow Through the Heart

1. The blood flows into the vena cava into the right atrium. It is deoxygenated blood.
2. The valves open and allow the blood flow into the right ventricle. The valves close.
3. The right ventricle contracts, valves open and blood is pushed... (More)