Across
- 4. process of breathing out
- 7. form a clot to stop bleeding
- 9. two cavities inside the nose
- 10. protect the body against infections
- 12. transports nutrients and gases
Down
- 1. two branches of the trachea
- 2. transports nutrients, oxygen, and waste substances
- 3. process of breathing in
- 5. two sponge-like organs
- 6. pumps the blood around the body
- 8. tiny air sacs at the end of the bronchioles
- 11. tube made up of rings of cartilage