The respiratory system

The respiratory system is made up of organs that help us breathe.

We breathe in oxygen from the air and breathe out carbon dioxide.

We breathe in air through the nose and mouth. The pharynx, a cavity behind the nasal (nose) and oral (mouth) cavities, opens and the air goes down a tube called the trachea.

The air then travels down two tubes called bronchi and enters the lungs.

The oxygen from the air passes from the lungs into our blood.

When we breathe in, a sheet of muscle called the diaphragm contracts to allow our lungs to fill with air.

When we breathe out, the diaphragm relaxes and the carbon dioxide leaves our lungs.

Try this quiz!!!!