Respiratory System

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Across
  1. 3. firm, flexabile connective tissue in structures such as the ear and nose
  2. 4. an organ situated within the ribcage and is the main part of the respitory system
Down
  1. 1. a large membranous tube reinforced by the rings of cartilage.
  2. 2. the movement of a substance from an area of high concentration to an area of lower concentration.