Across
- 3. oxygen and ... are needed for aerobic respiration
- 8. the process oxygen is inhaled and carbon dioxide is exhaled is called
- 11. blood cells that fight infections and protect the body from germs
- 13. to prevent backflow of blood
- 15. substance that make person very difficult for a person to quit smoking
- 17. largest artery in the human body
- 18. tiny air sacs in the lungs where oxygen enters the blood
- 20. smoking increases the risk of .... eye problem
Down
- 1. carries oxygenated blood from the lungs to the heart
- 2. tube that carries air from the throat to the lungs
- 4. tiny blood cell fragments that help stop bleeding by forming clots
- 5. layered membrane that surrounds the lungs and provides lubrication
- 6. Blood vessel that leaves the right ventricle to travel to the lung
- 7. chamber of the heart that pump blood to the entire body
- 9. type of blood vessel for gas exchange and extremely thin
- 10. bronchi transport air from … to lungs
- 12. bronchi to become restricted (get smaller) so air can't get to the lungs.
- 14. muscle below the lungs that helps you breathe in and out
- 16. exercise that strengthens the heart and improves blood circulation
- 19. anaerobic respiration need the substance