| A | B |
|---|
| Ecology | the study of the relationship of organisms to their environment |
| Community | all the organisms that live in an ecosystem |
| Habitat | physical location where an organism lives |
| Ecosystem | self-sustaining collection of organisms and their physical environment |
| Diversity | measure of the number of species living in an ecosystem |
| Producer | autotroph in an ecosystem |
| Consumer | organism that obtains energy by eating other organisms |
| Decomposer | organism that obtains its energy by consuming organic wastes |
| Trophic Level | group of organisms whose energy source is the same number of steps away from the sun |
| Autotroph | organism that makes its own food |
| Heterotroph | organism that cannot make its own food and must feed on another organism or its waste |
| Herbivore | consumer that eats only plants |
| Carnivore | flesh eating organism |
| Omnivore | organism that eats both plants and animals |
| Nitrogen Fixation | conversion of atmospheric nitrogen to ammonia by bacteria |
| Greenhouse Effect | warming of the Earth's atmosphere resulting from heat trapped by carbon dioxide and other gases |
| Plankton | floating or weakly mobile aquatic bacteria, protists, and animals |
| Biome | major type of terrestrial ecological community |
