Respiratory system.

All our muscles and organs need oxygen to function.

We breathe in Oxygen.

We breathe out carbon dioxide.

Oxygen enters our blood when we breathe in.

Carbon dioxide leaves our body when we breathe out.

The respiratory system is made up of:

NostrilsWindpipe

Bronchi

Lungs

Diaphragm

The air enters the nostrils

The nostrils have lots of little hairs to stop any object (like dust and insects).

When an object gets in, we sneeze it out.

The air passes through the

windpipe (or trachea).

The trachea is divided in two tubes called bronchi.

In the lungs there are alveoli.

Oxygen passes into the blood.

Carbon dioxide passes into the air.

Alveoli are little sacks sorrounded by blood capillaries.

When we breathe in

Our diaphragm goes down

When we breathe out

Our diaphragm goes up

And in a secret laboratory in mystery town…

A very clever scientist investigates the respiratory system…

To be continued…