Respiratory System

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Across
  1. 2. Taking air into the lungs
  2. 5. Muscle located under the lung
  3. 8. Letting air out of the lungs
  4. 9. Main organ of the respiratory system
Down
  1. 1. Filters the air we inhale and branches into the windpipe
  2. 3. tubes Tubes which leads from windpipe to each lung
  3. 4. Bone structure which protects the heart and lungs
  4. 6. A substance that moistens the air as well as trapping foreign substances
  5. 7. Allows air to enter and leave the body