Across
- 1. main organ for gas exchange
- 4. passage way to lungs
- 5. main airways that distribute glasses in the lungs while breathing
- 7. tiny air sacs that absorb O2 and release CO2 from capillaries
- 8. muscle that assists with breathing
Down
- 2. entryway for oxygen
- 3. blood vessels that pick up O2 and deliver CO2
- 6. another entryway for oxygen