Across
- 3. An opening in the nose where incoming air is warmed and filtered
- 6. A thin layer that forms a barrier
- 10. A tiny air sac in a lung where gas exchange occurs
- 12. A gas needed by cells to release energy
- 15. A body part that performs a specific function
- 18. The main airway between the throat and the lungs
- 19. The process used by all living cells to release energy
- 20. An organ where gas exchange occurs between air and blood
Down
- 1. A thin band of muscle between two ribs that helps with breathing
- 2. A tiny blood vessel where substances pass to and from the blood
- 4. The movement of molecules from an area of high to low concentration
- 5. A large sheet of muscle that contracts to draw gas into the lungs
- 7. A flap of cartilage that stops food entering the trachea
- 8. A gas produced as waste when cells release energy
- 9. A group of organs that work together to perform a function
- 11. The movement of oxygen into the blood and carbon dioxide out of it
- 13. A tube that carries air through a lung
- 14. The process used by animals to exchange gases with the atmosphere
- 16. The upper part of the trachea, containing the vocal cords
- 17. The common pathway for air and food