Across
- 1. Maintain an original state
- 3. Energy from the sun
- 5. Production of gas or radiation
- 9. Contaminating water or air with harmful chemicals
- 11. Conditions that an animal lives in
- 13. A animals or insects or persons natural living place
- 14. Dropping trash to the ground
- 15. Biology that deals with living organisms
- 19. To reuse a used item (like plastic
- 20. How the environment and the animals interact with each other
Down
- 2. A species that is no longer living
- 4. A reusable material
- 6. Able to be maintained at a certain rate or level
- 7. Creating a higher product than its original state
- 8. Recycling organic materials for fertilizer
- 10. Well-engineered and managed facilities for the disposal of solid waste
- 12. The gasses surrounding the earth
- 16. Colorless unstable toxic gas
- 17. Protecting an environment from destruction
- 18. Made from growing or living materials