William Harvey, a doctor from the 1600s, discovered that the heart is a muscular organ that pumps blood throughout the body. He also found out that there are four chambers in the heart: right atrium, left atrium, right ventricle, and left ventricle. These chambers help to move blood through the body by contracting and relaxing.
The heart is located in the chest between your lungs. It weighs about 10 ounces (283 grams) and is about the size of a fist. The heart beats about 100,000 times per day!
Blood flows through the body in two directions: arterial and venous. Arterial blood carries oxygen and nutrients to your body’s tissues while venous blood carries carbon dioxide and other waste products away from your tissues back to your lungs where they are exhaled out of your body as you breathe normally again. Your blood vessels carry this blood throughout your body by sending it through arteries which go up towards your brain (carotids), then down towards your legs (femoral). All of this happens without us even realizing it because our hearts are so strong!
