Across
- 2. Muscular tube behind the nose and mouth; shared by the respiratory and digestive systems.
- 3. Organs that expand and contract as you breathe.
- 4. Tiny air sacs where gas exchange takes place.
- 6. Two large passages that split from the trachea to the lungs.
- 9. The first structure air enters; filters, warms, and moistens air.
- 11. Tube that carries air from the throat to the bronchi; lined with cartilage rings.
- 13. The smaller branching air tubes inside the lungs.
- 15. Main muscle responsible for breathing; contracts during inhalation.
- 16. Tiny blood vessels surrounding the alveoli where gas exchange occurs.
Down
- 1. Gas that enters the blood during inhalation.
- 5. Flap of tissue that covers the trachea during swallowing to prevent choking.
- 7. system Organ system responsible for bringing oxygen into the body and removing carbon dioxide.
- 8. dioxide Gas released as a waste product during exhalation.
- 10. Structure containing the vocal cords; also called the voice box.
- 12. Breathing in; diaphragm moves downward.
- 14. Breathing out; diaphragm relaxes upward.
- 15. The process in which oxygen and carbon dioxide move by concentration differences.