Across
- 3. Injection that prevents disease
- 5. Center of an atom
- 7. Electric potential difference
- 9. Negatively charged atomic particle
- 10. Complete set of DNA in an organism
- 14. Cell division process
- 15. How plants convert sunlight to food
- 16. Element essential to all life
- 17. Preserved remains of ancient life
- 20. Protein that speeds up reactions
- 21. Pure substance on the periodic table
- 22. Noble gas that makes balloons float
Down
- 1. Lightest and most abundant element
- 2. Splitting an atomic nucleus
- 4. Physics of very small particles
- 6. Force that keeps us on Earth
- 8. Temperature scale where water freezes at zero
- 11. Water movement through a membrane
- 12. Positively charged atomic particle
- 13. Splits white light into colors
- 14. Object that attracts iron
- 18. Gas we breathe to survive
- 19. Range of light wavelengths
- 20. When one celestial body blocks another