organ system

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Across
  1. 3. voice box
  2. 5. the sac that exchange gas in the lungs
  3. 7. throat
Down
  1. 1. tubes that branched from windpipe to each lung
  2. 2. tube that carry air from neck to lungs
  3. 4. the dome-shaped muscle that divide the thorax and abdomen
  4. 6. the main organ in the respiratory system