Respiratory structures

3. The flap of cartilage that covers the windpipe during swallowing to prevent choking.
5. The muscle separating the chest and abdomen; it contracts during inhalation.
7. The throat; a common passageway for both food and air.
8. The lower part of the lung resting on the diaphragm.
10. Fine hair-like structures in the nose that filter foreign bodies.
11. The process of breathing air into the lungs.
13. The "voice box" containing the vocal cords.
14. The scientific term for the "windpipe".
17. The uppermost part (tip) of the lung.
19. The gas that passes from the alveoli into the pulmonary capillaries.

1. The overall process of exchanging gases between the atmosphere and body cells.
2. The midline region where bronchi, blood vessels, and nerves enter and exit the lungs.
4. The smallest branches of the bronchi that lead to alveolar ducts.
6. Tiny air sacs at the end of bronchioles where gas exchange occurs.
9. Tiny blood vessels surrounding the alveoli for gas exchange.
12. The process of breathing air out of the lungs (synonym: Expiration).
15. The gas produced by cells and expelled from the lungs.
16. The double-folded membrane surrounding each lung.
18. A division of the lung (The right lung has 3, the left lung has 2).