Across
- 3. The bones that protects your lungs
- 5. A 4 meter long tube in your throat
- 6. The opposite of oxygen
- 7. The net passive movement of molecules
- 10. How Co2 becomes red blood cells
- 12. Air passages inside the lung
Down
- 1. The smallest of the blood vessels
- 2. The sense of smell
- 4. Air passages that connect to the lungs
- 8. What humans breathe
- 9. A thin skeletal muscle at the base of the chest
- 11. The organ we use to breathe