Across
- 1. Air sac where gas exchange occurs.
- 5. Separate lungs and thorax.
- 7. The blood vessels that covered the alveolus.
- 8. Movement of molecules from high to low concentration area.
Down
- 2. A disease related to respiratory system.
- 3. Pigment in red blood cells which combines with oxygen.
- 4. Carcinogenic substance that causes lung canser.
- 6. An addictive substsnce thst causes bronchitis.