Across
- 2. the muscle that helps your lungs expand
- 3. tubes that branch out from the bronchial tubes
- 4. the number of times a person inhales in one minute
- 6. 20% of air enters through here
- 8. the process in which the body takes in fresh air, containing oxygen, and forces out used air, containing carbon dioxide
Down
- 1. your windpipe
- 3. two tubes that branch out from the trachea
- 5. to breathe out
- 7. airsacs
- 9. to breathe in