Across
- 4. under the lungs
- 6. co2
- 8. major air passages of the lungs
- 9. the most important part of the respiratory system
Down
- 1. a tube where air gets in
- 2. an opening to our windpipe
- 3. tiny air sacs of the lungs
- 5. something that is waste in your body
- 7. protects your lungs