Across
- 4. site of gas exchange between oxygen and carbon dioxide
- 6. fine blood vessel which surrounds alveoli
- 7. our windpipe
- 8. opens to nasal cavity
- 9. large organ made up of many air sacs
- 10. opening of trachea
Down
- 1. Flap of cartilage that closes over the trachea when you swallow
- 2. filters air particles
- 3. voicebox
- 5. branch of bronchi
- 8. cavity filters and moistens air