1. The Respiratory System
Video (3min 22sec):

2. The Respiratory System
This organ system that is made up of the trachea, bronchioles, lungs, alveoli and other structures
It connects the lungs to the outside
Its function is taking in oxygen and removing carbon dioxide

3. Breathing
Hiccups happen when the diaphragm quickly contracts, letting air in quickly, snaping shut the epiglottis

4. The Respiratory System
How do we keep food from going down the trachea? Epiglottis is a flap of tissue that covers the trachea when we swallow food.

5. Gas Exchange
Alveoli have very thin walls, and are surrounded by capillaries
Oxygen diffuses through the walls of the alveoli, through the capillary walls, and into the blood stream
Carbon dioxide in the blood diffuses from the capillaries into the alveoli, which is then exhaled by the lungs

6. Gas Exchange in the Alveoli

7. Your turn
Outline the path oxygen takes going from the air, to your lungs (alveoli)
Outline the path carbon dioxide takes going from your lungs (alveoli) to the air.
How does breathing result in gas exchange?