respiratory system

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Across
  1. 1. the tube that connects mouth and lungs
  2. 4. the trachea is dividad into 2 ...
  3. 6. muscle that helps us to breathe, under the lungs
  4. 7. the action of "take in air"
Down
  1. 2. the exchange of gases happens here
  2. 3. the gas we need to live
  3. 5. small blod vessels that carries oxygen and carbon dioxide