| A | B |
| food chain | the path by which energy is passed from one living thing to another |
| food web | the combined food chains in a habitat or eco system |
| habitat | a place where a population of plants and animals live and interact with their environment |
| population | the living things of the same kind that live in an environment |
| community | the different populations of living things that live together in an environment |
| ecosystem | the living and non-living things such as air, water, sunlight, and soil in an environment |
| succession | a series of changes in an ecosystem and the communities found in an ecosystem |
| symbiosis | a partnership between living things |