Across
- 1. Flat bone located in the middle of the chest
- 4. Tiny balloon shaped air sacs
- 5. Activities that don't require oxygen
- 8. Process of taking in oxygen and getting rid of carbon dioxide
Down
- 2. Scientific name for chest
- 3. Main airway into the lungs
- 4. Activities that require oxygen
- 6. Byproduct of anaerobic respiration
- 7. Smallest blood vessel in the body