Across
- 2. what is one thing that respiration produce
- 4. makes lung contract
- 9. makes sounds
- 10. passage that direct air into the lungs
Down
- 1. what moisten cleans and warms the air
- 2. what is another name for trachea
- 3. movement of air into and out of the lungs
- 5. breathing is controlled by
- 6. what is another name for pharynx
- 7. Dark sticky substance that is formed when tobacco burns
- 8. what is the main organ of the respiratory system