1. Respiratory System

2. Purpose of the Respiratory System
To provide a constant supply of oxygen to keep your body cells functioning
To remove carbon dioxide from the body cells

4. Nostrils/Nasal Cavity
Nostrils bring air into the body
Nasal hair traps dust
Air is moistened and warmed in the nasal cavity
Mucus produced by glands traps dust, pollen and other materials not trapped by the nasal hair
cilia (tiny, hairlike structures) sweep mucus and trapped material to the back of the throat where it can be swallowed

5. Pharynx
a muscular structure at the top of the trachea, containing the vocal cords
used by food, water and air
Epiglottis - flap of tissue that folds down to prevent food and water from entering the airway

6. Larynx and Trachea Larynx Trachea Voice box
Airway to which the vocal cords are attached
windpipe
the tube through which air travels from the larynx to the lungs.
Strong cartilage prevents the trachea from collapsing
Lined with mucous membranes and cilia to trap dust bacteria and pollen

7. Bronchi Two short tubes that branch off the lower end of the trachea
Bronchi branch into smaller tubes
The smallest tubes are called bronchioles
Carry air into the lungs.

8. Alveoli
Tiny, thin-walled, grapelike clusters at the end of each bronchiole
Surrounded by capillaries
Where carbon dioxide and oxygen exchange take place

9. Breathing and Respiration

10. When you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward.
When you breathe out, or exhale, your diaphragm relaxes and moves upward into the chest cavity.