| A | B |
| natural resource | something found in nature that is used |
| recyclable resource | is used over and over without destroying |
| renewable resource | is destroyed but can be replaced |
| nonrenewable resource | cannot be replaced once used |
| humus | decayed pland and animal material that makes soil fertile |
| biotic resources | resources from living things |
| fossil fuels | oil, coal, natural gas |
| salt | nonmetallic mineral important to human health |
| adaptation | how plants and animals adjust to their environment |
| types of coal | peat, lignite, bituminous, anthracite |
| strip mining | removes topsoil to get at coal near surface |
| alternative energy resources | wind, water, solar, geothermal, tides, etc. |
| fresh water | only makes up about 3% of total water supply |