Across
- 5. it is what we exhale
- 8. It is the second airway in the system
- 10. It is the main way we breathe
- 11. tiny branch of air tubes
- 12. High and low concentration
Down
- 1. Thin blood vessels
- 2. it is the first airway in the system
- 3. it contracts involuntarily
- 4. It is what we inhale
- 6. Provides support while breathing
- 7. It is one of the main ways to breathe
- 9. Air sacs that exchange oxygen