Why does your body need air? How do you breathe? Why is exercise good for your body? Your body is amazing! There are parts you can see and parts under your skin that you can't see. These parts work together to keep you alive and help you to do incredible things. You need to breathe to stay alive. Have you ever wondered why, or wanted to know what happens to the air you breathe in? Read this book in the 'Body Systems' series to find out!
