respiratory system
Across
- 1. contains cells
- 4. plural form of bronchus.
- 6. any of the minute branches into which a bronchus divides.
- 8. membrane-lined cavity behind the nose and mouth
- 9. :a dome-shaped muscular partition
Down
- 2. helps you breath
- 3. large membranous tube reinforced by rings of cartilage: flabby skin surrounding something
- 5. breathes oxygen
- 7. bony frame formed by the ribs round the chest