Across
- 4. a structure that surrounds the cell
- 5. large body of air
- 7. harmful material in the air
- 8. most meteorites burn up
- 10. dark clouds when it rains
- 12. lower layer of atmosphere
- 15. the control center of the cell
- 17. where photosynthesis occurs
- 18. power house of the cell
- 19. Cell organelle that stores materials
- 20. a tiny cell structure that carries out
Down
- 1. the condition of the air
- 2. light energy from the sun
- 3. a cell that controls what can enter
- 6. layer of the thermosphere
- 9. wispy feathery clouds
- 11. pattern of wind
- 13. water vapor in the air
- 14. mid level clouds
- 16. made of a single cell