Respiratory system
Across
- 4. voice box for animal
- 5. external openings
- 7. sheet of muscle below the lungs
- 8. valve like structure that shuts when swallowing food
Down
- 1. common passageway for food and air but not same time
- 2. two elastic spongy material that fill with air
- 3. smallest bronchioles, exhausts carbon dioxide
- 6. two tubes from trachea