Across
- 4. windpipe
- 7. passagewayforairandfood
- 11. bloodVessel
- 13. sleepy
- 14. smalltubes
- 17. bloodandbodytissues2ndphase
- 18. tubesthatbranchoutfrtrachea
- 19. airsacs
Down
- 1. filter
- 2. vocalcords
- 3. sheetofmusclebelowchestcavity
- 5. breathingout
- 6. trap
- 8. mechanicalprocess
- 9. exchange
- 10. incompleterings
- 12. absorbbacterialarynx
- 15. 1stphase
- 16. entrance