Breathe in... The air comes into your nose.
Breathe out... The air comes out.

Look inside the nose...

Hello! We are little bugs living inside your nose and lungs.

Hello! We make snot and bogeys to trap dirt and dust.

Healthy lungs have lots of different kinds of bugs. But too many of some types of bugs can make you poorly.

Breathe in... The air comes into your nose.
Breathe out... The air comes out.

The air goes down in a big breathing tube and goes into each lung.

The air is inside the lungs. The breathing tubes in the lung look like a tree!

At the end of each branch of the breathing tubes there are little air bags called alveoli.

The air reaches the alveoli.

Oxygen from the air you breathe goes inside the body. All the cells in your body need oxygen which is why breathing is so important.

Breathe in... The air comes into your nose.
Breathe out... The air comes out.

Dirt and smoke in the air can go inside your lungs when you breathe in.

Smoke and dirt can sometimes cause sneezes and wheezes and coughs when you breathe in lots of it.

Breathe in... The air comes into your nose.
Breathe out... The air comes out.

Tiny grains of pollen are spread in the air by trees and other plants. Pollen in the air can go inside your lungs when you breathe in.

Pollen can sometimes cause sneezes and runny noses and itchy eyes when you breathe lots of it in.