.

123456789101112
Across
  1. 2. tiny hair in your respiratory system
  2. 3. this regulate temperature and humidity of the air
  3. 5. the lungs fill in?
  4. 8. tube that delivers air from your mouth and nose to the trachea
  5. 10. small branches that lead to the alveoli
  6. 11. these are classified millions of microscopic air sacs called -------?
  7. 12. external extension of fishes are called
Down
  1. 1. also called as voice box
  2. 4. found on land and transport oxygen and carbon dioxide in their skin
  3. 6. used in photosynthesis in exchange of Oxygen
  4. 7. a major organ that expands and contracts
  5. 9. Gas pass through pores called ---- in the epidermis