Nature and Ecology

4. The protection and preservation of the natural environment
9. Decayed organic material used as fertilizer
11. A group of living organisms consisting of similar individuals capable of interbreeding
12. The ability to be maintained at a certain rate or level
15. Capable of being renewed or sustained
16. The surroundings or conditions in which a person, animal, or plant lives
18. A biological community of interacting organisms and their environment
20. A large naturally occurring community of flora and fauna occupying a major habitat

1. A mutually beneficial relationship between different organisms
2. The process by which green plants use sunlight to synthesize foods
3. The natural home or environment of an animal, plant, or other organism
5. Derived from living matter
6. The process by which pollen is transferred from the male part of a plant to the female part
7. The prevailing weather conditions of an area over a long period
8. The variety of plant and animal life in a particular habitat
10. A chemical element that is the basis of all life
13. An animal that naturally preys on others
14. A change by which an organism becomes better suited to its environment
17. An animal that is hunted and killed by another for food
19. To convert waste into reusable material