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