Respiratory System

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Across
  1. 2. What happens to your muscles when you exhale
  2. 4. The two passages that direct air into the lungs
  3. 6. Main organ of the respiratory system
  4. 7. The exchange of gases between the inside and outside of the body
Down
  1. 1. The windpipe
  2. 3. Tiny thin-walled sacs of lung tissue
  3. 5. Cellular _______ is the process cells use to break down glucose