Across
- 4. percent of oxygen in atmospheric air
- 8. voicebox
- 9. direction diaphragm moves on inhale
- 11. respiratory gas that is expelled to outside air
- 12. airway that extends from the larynx to the carina
- 14. valve separating esophagus from larynx
- 15. membranes that surround the lungs within the thorax
Down
- 1. most abundant gas in the atmosphere (78%)
- 2. network of bronchial tubes extending from trachea to alveoli
- 3. blood vessels surrounding alveoli
- 5. terminal sacs where external respiration occurs
- 6. tissue folds in larynx creating sounds as air blows over them
- 7. atmospheric gas that diffuses into alveoli from outside air
- 10. cavities in skull lined with mucus membranes
- 13. muscles between the ribs that elevate the ribs during inspiration