Across
- 3. small, spongy air sacs where gas exchange happens
- 6. the dome-shaped muscle under the lungs
- 8. the windpipe
- 9. to breathe out
- 11. the voice box
- 12. the two main organs we use to breathe
- 15. little air passages in the lungs
- 16. the vein that takes oxygen-rich blood from the lungs to the heart
- 19. A process: sugar + oxygen => carbon dioxide + energy + water
- 20. to breathe in
- 21. the type of muscles between the ribs
- 22. the gas we need for cellular respiration
- 23. we breathe in through this organ
Down
- 1. the two openings in the nose, filled with hairs inside
- 2. the two tubes connecting the trachea to the lungs that are lined with cilia
- 4. the cells that transport gases in the bloodstream
- 5. the part of the throat behind the nasal passage and the mouth
- 7. the tiny blood vessels around the alveoli
- 10. the artery that takes carbon dioxide-rich blood from the heart to the lungs
- 13. special tiny hairs that move mucus up to the mouth
- 14. the part of the respiratory tract consisting of the nasal cavity
- 17. a sticky substance that collects dust and germs from the air we breathe in
- 18. the gas we breathe out