| A | B |
|---|
| the place where an organism lives | habitat |
| organisms in the ecosystem that belong to one species | population |
| a close relationship between species | symbiosis |
| the study of interactions among organisms and their environment | ecology |
| all the organisms living in an area and the nonliving features of their environment | ecosystem |
| a symbiotic relationship in which one partner benefits but the other is not affected | commensalism |
| how an organism survives in its environment | niche |
| organisms that use an outside energy source to make energy-rich molecules | producer |
| a symbiotic relationship in which one organism benefits but the other is harmed | parasitism |
| a symbiotic relationship in which both species benefit | mutualism |
| all the populations in an ecosystem | community |
| organisms that cannot make their own energy-rich molecules | consumers |
| anything that restricts the number of individuals in a population | limiting factor |
| the feeding relationships among the organisms in an ecosystem | food web or chain |
| the part of Earth that supports life | biosphere |
