1. The Human Body A closer look at your Heart in Action

2. The Human Heart Muscle –Pumps blood Not the typical heart –Upside-down pear Size of clenched fist –Weighs 11 ounces

3. Four Chambers Atrias- top 2 chambers –Left –Right Ventricles- bottom 2 chambers –Left Pumps blood to rest of body Is the strongest –Right

4. Valves There are four valves Help to direct blood flow Opening and closing causes it to make a beating sound –This is why the doctor uses a stethoscope to see if your valves are working correctly.

5. Interesting Facts The human heart beats 40 million times a year. It pumps 4300 gallons of blood a day. Beats about 72 times a minute It will have beaten 2.3 billion times when you are 70 years old. Your heart pumps 2.4 ounces a heart beat