Respiratory System Crossword Puzzle

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Across
  1. 1. Gelatinous, slippery fluid that traps dust and other particles entering the respiratory system.
  2. 4. Primary function of the respiratory system (2 words).
  3. 7. Process of gas exchange in the body.
  4. 8. Tubes from the trachea to the lungs.
  5. 9. The left lung is smaller than the right lung to make room for this organ.
Down
  1. 1. Secondary external opening that brings air into the respiratory tract.
  2. 2. The bronchi are part of this respiratory system.
  3. 3. Exhalation occurs when the air pressure in the lungs is __________ than outside the body.
  4. 5. Prevents food from entering the airway.
  5. 6. The diaphragm separates the thorax (chest) from this region in the body.