the respiratory system

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Across
  1. 1. windpipe
  2. 3. airway
  3. 5. muscle for inflating
  4. 7. organ that collects air
  5. 10. protect organs
  6. 11. where you get air from
  7. 12. a heavy gas
Down
  1. 2. air sacs that exchange oxygen
  2. 4. blood vessels
  3. 6. movement of molecules
  4. 8. hole to breathe from
  5. 9. small air tubes