The Respiratory system

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Across
  1. 1. main organ for gas exchange
  2. 4. passage way to lungs
  3. 5. main airways that distribute glasses in the lungs while breathing
  4. 7. tiny air sacs that absorb O2 and release CO2 from capillaries
  5. 8. muscle that assists with breathing
Down
  1. 2. entryway for oxygen
  2. 3. blood vessels that pick up O2 and deliver CO2
  3. 6. another entryway for oxygen