Across
- 2. system that works together with respiratory
- 6. another word for breathing in
- 8. used to inhale and exhale
- 9. synonym for the windpipe
Down
- 1. dome shape muscle involved in breathing
- 3. dioxide air that we breathe out
- 4. tiny air sacs in the lungs
- 5. air that we breathe in
- 7. another word for breathing out