The Respiratory System

123456789101112131415161718192021
Across
  1. 2. The more commonly-used name for the 'pharynx'.
  2. 5. One of the many passageways which branch off of the bronchi within the lungs.
  3. 7. A large muscle which controls the size of the chest cavity. It contracts and then relaxes to enable a person to breath in and out, respectively.
  4. 9. The number of lungs, nostrils and bronchi humans have.
  5. 11. Forms the initial part of the digestive system, in addition to one of the initial parts of the respiratory system - the _______ cavity.
  6. 12. The 'primary' organs of the respiratory system.
  7. 13. The tubes which lead into each lung from the trachea.
  8. 14. Our voice box
  9. 16. The hollow space located within the skull, behind the nose - nasal ____________.
  10. 17. The waste gas that we remove from the bloodstream and expel out into the air - carbon ___________.
  11. 18. The opposite of exhalation.
  12. 20. A reflex that humans use to expel potenially-harmful pathogens and irritants from the respiratory tract.
  13. 21. The millions of tiny sacs, within our lungs, that are responsible for the exchange of gases into/out of the bloodstream.
Down
  1. 1. CO2 is produced as a toxic bi-product of this chemical process that occurs within our cells.
  2. 3. The hairs which line the inside of nostrils are used to __________ out dust and coarse particles.
  3. 4. The process of producing sound from the mouth, using the vocal cords.
  4. 6. The rings that prevent the trachea from collapsing are made from this type of tissue.
  5. 8. The process of taking in and pushing out air from the lungs/mouth/nose.
  6. 10. The gas that we take in from the atmosphere and deliver to our bloodstream.
  7. 15. CO2 can influence this property of blood, since it combines with water to form weak acid.
  8. 19. The correct scientific name for the "windpipe".