Across
- 3. Fast breathing, low blood carbon dioxide
- 4. The process of air leaving the lungs
- 5. Bones that provide physical protection to the heart and lungs
- 7. Small branches of airways connected to the alveoli
- 8. Opening to the trachea
Down
- 1. The windpipe
- 2. Passageway at the back of the throat
- 4. A flap that closes on top of the trachea
- 6. Small pouches that form grape-like clusters
- 7. Branches off of the trachea