Across
- 4. Taking air into the lungs
- 6. A substance that moistens the air as well as trapping foreign substances
- 7. Bone structure which protects the heart and lungs
- 9. Muscle located under the lung
- 10. Filters the air we inhale and branches into the air tubes
Down
- 1. Letting air out of the lungs
- 2. Main organ of the respiratory system
- 3. The process of producing energy using sugar and oxygen
- 5. Allows air to enter and leave the body
- 8. tubes Tubes which leads from windpipe to each lung