Across
- 5. Essential gas for aerobic respiration.
- 8. Process of gradual development and change over time.
- 9. Transfer of pollen from male to female reproductive organs in plants.
- 10. Long-term alteration in Earth's climate patterns.
- 12. Cell division resulting in two identical daughter cells.
- 15. Unit of heredity that determines traits.
- 17. Essential element found in proteins and nucleic acids.
- 18. Biological community and its physical environment.
- 20. A massive system of stars, gas, and dust.
Down
- 1. Force that attracts two objects toward each other.
- 2. Element essential to life and found in organic compounds.
- 3. Subatomic particle with no electric charge.
- 4. Biological community and its physical environment.
- 6. Process in which two atomic nuclei combine to form a larger nucleus.
- 7. Preserved remains or traces of ancient organisms.
- 11. Study of celestial objects and phenomena.
- 13. Process by which green plants and some other organisms use sunlight to synthesize foods.
- 14. Capable of being decomposed by bacteria or other living organisms.
- 16. Genetic material carrying instructions for the development and functioning of living organisms.
- 19. Dense forest found near the equator, characterized by high rainfall and biodiversity.