Respiratory System

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Across
  1. 4. Located within the thoracic cavity and protected by the sternum, ribs and vertebral column
  2. 7. The respiratory system is a biological system consisting of specific organs and structures used for gas exchange in animals and plants
  3. 10. Each bronchus subdivides into smaller branches called bronchioles
  4. 12. Involuntary or smooth muscle that contracts and always relaxes to aid breathing
Down
  1. 1. the movement of substances from a high to low concentration through a semi-permeable membrane
  2. 2. Cup shaped sacs found at the end of bronchioles
  3. 3. Where the back of the mouth and nose meet
  4. 5. by capillaries, they provide the site for continual exchange of 02 and CO2
  5. 6. Where the air enters the respiratory system
  6. 8. 2 tubes that provide air to the lungs
  7. 9. Assists with air delivery. Also known as windpipe
  8. 11. Produces sound when air passes over the larynx