| A | B |
|---|
| pollution | the presence of harmful substances in the environment |
| renewable resource | any natural resource that can be used again and again |
| nonrenewable resource | a natural resource that cannot be used again or only after millions of years |
| overpopulation | when the population of an organism is too great for resources available to it causing the resources to become limiting factors |
| alien species | an organism that makes a home in a place other than its native environment |
| biodiversity | different species in an area "variety of life" |
| biodegradable | able to be broken down by the environment |
| conservation | the good management of natural resources |
| recycling | reusing trash |
| resource recovery | changing garbage into electricity |
