| A | B |
|---|
| individual | a single organism in an environment |
| population | organisms of the same kind living in the same environment |
| community | all the populations of organisms living together in an environment |
| ecosystem | the animals and plants in an environment along with its physical factors |
| habitat | the part of the environment where a population lives |
| niche | a population's role in the ecosystem |
| producers | capture the energy of the sun and change it into living tissue |
| consumers | these must eat to get the energy they need |
| food chain | shows how consumers in an ecosystem ar connected to one another according to what they eat |
| decomposers | thee break down the tissues of dead organisms |
| food web | shows the relationships between many food chains within a single ecosystem |
| energy pyramid | shows the amount of energy available to pass from one level of a food chain to the next |
| competition | when organisms must share limited resources |
| symbiosis | a long relationship between different kinds of organisms |
| instinct | a behavior that an organism inherits |
| learned behavior | a skill that an animal develops to help it survive |
| endangered | organisms that have populations so small that they are likely to die out if steps aren't immediately taken to save them |
| threatened | likely to become endangered if these organisms are not protected |
| extinct | when the last individual of a population dies |
