Lithosphere

3. a major ecological community type
4. Chain a hierarchical series of organisms each dependent on the next as a source of food
6. organisms that can form nutritional organic substances from simple inorganic substances
8. an organism deriving its nutritional requirements from complex organic substances
12. a process where green plants use sunlight to synthesize foods with carbon dioxide and water. Oxygen being a byproduct
13. animals that eat both meat and green foods
15. An autotrophic organism that serves as a source of food for other organisms in a food chain
16. animals that only eat meat
19. the region that is occupied by living organisms
20. a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding
21. a biological community of interacting organisms and their physical environment

1. the branch of biology that deals with the relations of organisms to one another and to their physical surroundings
2. Level each of several hierarchical levels in an ecosystem
5. interacting group of various species in a common location
7. the total mass of organisms in a given area or volume
9. synthesis of carbohydrate from carbon dioxide and water; limited to certain bacteria and fungi
10. groups of individuals belonging to the same species that live in the same region at the same time
11. an organism that decomposes organic material
14. animals that only eat green foods
17. Bloom rapid increase or accumulation in the population of algae in a water system
18. a substance that provides nourishment essential for growth and the maintenance of life