Respiratory System

Structure of the Respiratory System

Larynx – voice box

Trachea – windpipe

Bronchi – left and right to each lobe of lung

Bronchioles – smaller tubes leading to: Alveoli – small air sacs – site of gas exchange

1 of 6

Other Structures of the Respiratory System

Pleural membranes – cover and protect lungs

Diaphragm – dome shaped muscle separates chest from abdomen

Intercostal muscles – contract and relax to expand the chest volume

Pulmonary arteries and veins – move blood through the lungs

2 of 6

Functions of the Respiratory System

Inspiration/expiration (breathing!) 

Gaseous exchange of oxygen and carbon dioxide

3 of 6

Gas Exchange is Based on Passive Diffusion

A large surface area for exchange of gases

A short distance for the gases to diffuse

Concentration gradients for the gases

4 of 6

Alveoli are:

Numerous (large surface area)

Thin walled (short distance)

Surrounded by many tiny capillaries (keeps a concentration gradient)

To speed up diffusion!

5 of 6

Transport of Gases

Oxygen binds to haemoglobin to form oxyhaemoglobin

Carbon dioxide is dissolved in the blood plasma

6 of 6


No comments have yet been made

Similar Health & Social Care resources:

See all Health & Social Care resources »See all Anatomy and physiology in practice resources »