1. Respiratory System

2. Respiratory system/functions Nose: air enters Nose: air enters –Hairs block or trap dust and unwanted objects Nasal passage: warms air and adds moisture as it enters Nasal passage: warms air and adds moisture as it enters Larynx: flap that closes over trachea during swallowing Larynx: flap that closes over trachea during swallowing –Keeps food and liquid out of the lungs

3. Continued Trachea: tube that carries air from nasal Trachea: tube that carries air from nasal –Chamber to bronchi Bronchi: tube that carries air from trachea to the right and left lungs Bronchi: tube that carries air from trachea to the right and left lungs

4. Continued Lungs: main organ of respiratory system Lungs: main organ of respiratory system –Tiny air sacs and blood capillaries where oxygen moves into blood and carbon dioxide moves out

5. Continued Diaphragm: muscle at bottom of chest cavity Diaphragm: muscle at bottom of chest cavity –Moves up when relaxed and helps with breathing out –Moves down when contracted and helps with breathing in

6. Continued Capillaries: blood vessel that surrounds alveoli Capillaries: blood vessel that surrounds alveoli –Site of gas exchange between blood and air Alveoli: air sacs Alveoli: air sacs –Site of gas exchange between blood and air

7. Exhaling The chest cavity shrinks which pushes air out of the lungs The diaphragm relaxes

8. The End

9. Inhaling The chest cavity expands and so do the lungs. Air rushes in and fills the enlarged lungs. The diaphragm contracts.