| A | B |
|---|
| community | all the living things in an ecosystem |
| competition | the struggle among organisms for water |
| ecosystem | all the living and nonliving things in an environment and their interactions with each other |
| niche | the role of an organism in an ecosystem |
| overpopulation | too many of at least one kind of thing in an area compared to the available resources |
| population | all the members of one species in an area |
