What does the heart do?

Find out about how blood delivers oxygen and nutrients to every cell in the human body

How the circulatory system works

What is the heart?

The heart is a muscle. It pumps blood all around the body.

What is blood?

Blood is the transport system for our bodies.

It picks up and carries oxygen and nutrients to where they are needed. It also picks up waste products and helps transport them out of the body.

Blood is also part of the immune system. White blood cells fight off infections.

How does the circulatory system work?

The left side of the heart pumps blood that contains oxygen around the body through arteries.

When blood passes the intestines, it picks up nutrients that have been absorbed from food.

Blood travel from arteries into capillaries. These deliver oxygen and nutrition to every cell in the body and pick up waste products including carbon dioxide.

Veins take the blood back to the right side of the heart. It is then pumped to the lungs.

The lungs absorb carbon dioxide and the blood absorbs oxygen. It then travels back to the left side of the heart, ready to be pumped around the body again.

The heart is so strong that this whole process only takes about one minute!