ECOLOGY VOCABULARY REVIEW

2. Organisms that feed on other organisms.
5. A group of ecosystems that share similar climates and typical organisms.
7. The parts of Earth on which life exists.
8. A layer of permanently frozen soil.
10. Cycles in which elements, chemical compounds, and other forms of matter are recycled from one organism to another and from one part of the biosphere to another.
14. Wetland where the river meets the ocean.
15. Zone in the water where sunlight can reach.
16. The scientific study of interactions among organisms and between organisms and their environment.
17. Process of converting nitrogen gas into nitrogen compounds.
19. Process where chemical energy is used to produce food like carbohydrates.
20. A group of individuals in the same species that live in the same area.
22. The total mass of living tissue within a trophic level.
23. Living things within the environment that interact with other organisms.

1. Process by which nitrates are converted back to nitrogen gas by bacteria.
3. Also called heterotrophs, they get energy by feeding on other organisms.
4. The physical or nonliving part of the environment like sunlight.
6. Different populations that live together in a defined area.
9. Organisms that use chemicals or sunlight to make their own food.
11. Pyramid showing the relative amount of energy or matter contained within each trophic level in a food chain or food web.
12. A group of similar organisms that can interbreed and produce fertile offspring.
13. Series of steps in which organisms transfer energy by eating and being eaten.
15. Type of first producer of energy-rich compounds.
18. Zone in the ocean where sunlight does not get to.
21. _______ levels, which are steps in a food chain or food web.