| A | B |
|---|
| population | a group of organisms of the same species living together in the same area |
| community | all the different organisms that live together in an ecosystem |
| environment | all the living and nonliving things that an organism may interact with |
| ecosystem | all living and nonliving things in a given area that interact with one another |
| habitat | the place in which an organism lives and obtains the resources it needs to survive |
| producer | an organism that is unable to make its own food by using a source of energy to turn simple raw materials into food |
| consumer | an organism that cannot make its own food |
| decomposer | an organism that breaks down the bodies of dead organisms into simpler substances |
| food chain | a representation of a series of events in which food energy and matter are transferred from one organism to another |
| food web | a diagram that consists of many overlapping food chains |
| competition | the type of interaction in which organisms struggle with one another to obtain resources |
| predator | an organism that kills and eats another organism |
| prey | an organism that is eaten by a predator |
| symbiosis | a close relationship between two organisms in which one organism lives near, on, or even inside another organism and in which at least one organism benefits |
| commensalism | a form of symbiosis in which one organism benefits and the other is not harmed |
| mutualism | a form of symbiosis in which both organisms benefit |
| parasitism | a form of symbiosis in which one organism benefits and the other is harmed |
| host | an organism that provides a home for another organism |
| niche | an organisms' role in an ecosystem which includes everything the organism does and needs |
| ecology | the study of relationships and interactions of living things with one another and their environment |
