pathway of air through respiratory system

How does oxygen enter the body

Through our mouths and noses, passing into the nasal cavity where it is warmed and moistened

What happens to oxygen after that

It then travels to the lungs and diffuses into the bloodstream

What happens to carbon dioxide in the respiratory system

Passes in opposite direction to oxygen, exiting the body

The trachea

The air moves into the trachea, which is supported by cartilage rings to stay open

Ciliated cells inside trap dust

The trachea then splits into 2 bronchi, leading to lungs

Bronchi and bronchioles

• lungs split into 2 bronchi, with right bronchi leading to right lung and left to the left lung

• These bronchi divide into smaller bronchioles, narrow tubes less than 1mm in diameter

What are alveoli

Tiny air sacs responsible for gas exchange between the lungs and blood

How many alveoli are there and what does it cause

Millions of them provide a large surface area

Alveoli thin walls

Their thin walls, lined with a film of water l, help dissolve Oxygen from inhaled air

Function of respiratory system

To provide oxygen and remove carbon dioxide