Across
- 2. very thin blood vessels
- 4. You use this to smell
- 7. muscle that inflates lungs
- 8. connects bronchus to alveoli
- 9. 02
- 11. molecules from high to low concentration
Down
- 1. bone casing
- 3. exchanges oxygen and carbon dioxide
- 5. sends air to lungs
- 6. C02
- 8. splits air into lungs
- 10. collects air