Our lungs are...................................

• Soft and spongy.

• They expand as you breathe in and contract as you breathe out.

• Controlled by 3 muscles intercostal muscles, heart muscle and diaphragm muscle.

• Protected by ribs.

Bands of muscle between your ribs.

• Intercostal muscles

• Diaphragm muscle

A thick sheet of muscle that separates your heart and lungs from the rest of your organs.

• Intercostal muscles

• Diaphragm muscle

A strong tube that carries air down from your nose and mouth.

• Bronchi

• Trachea

• Alveoli

The two large tubes that carry air from your trachea to your lungs.

• Bronchi

• Bronchiole

• Alveoli

The smaller branches-subdivided tubes- of the bronchus.

• Arteries

• Bronchiole

• Alveoli

A cluster of tiny air spaces found at the end of each bronchiole.

• Arteries

• Trachea

• Alveoli

Arteries, carrying blood to the alveoli threaded between the bronchioles are shown blue on the model.

• True

• False

Each alveolus is surrounded by a network of capillaries.

• True

• False

The walls of the capillaries and alveoli are very thick to help in gas exchange.

• True

• False