Across
- 2. site where gas exchange occurs and made of air sacs
- 4. the act of breathing
- 8. where air passes through
- 10. a muscle that contracts and expands to assist breathing
- 11. an automatic process we do to survive
Down
- 1. branch that leads to the lungs
- 3. 2 organs that assist breathing
- 5. breathing out
- 6. breathing in
- 7. the diaphragm does this when breathing out
- 9. the diaphragm does this when breathing in