It's Great to Circulate!

You probably guessed that the blood just doesn't slosh around your body once it leaves the heart. It moves through many tubes called arteries and veins, which together are called blood vessels. The movement of the blood through the heart and around the body is called circulation (say: sur-kyoo-lay-shun), and your heart is really good at it — it takes less than 60 seconds to pump blood to every cell in your body.Your body needs this steady supply of blood to keep it working right.The left side of your heart sends that oxygen-rich blood out to the body.