| A | B |
|---|
| succession | the gradual change in organisms that occur when the environment makes a change on an ecosystem |
| pioneer species | first hardy species such as microbes, mosses, and lichens that are in the first stage of ecological succession |
| natural resources | materials found in nature that are used by organisms |
| pollution | the release of harmful materials into the environment harming our natural resources |
| biodegradable | refers to a substance that can be broken down by decomposers into harmless chemicals which are released back into the ecosystem safely |
| endangered species | one that is near extinction |
| threatened species | one that is near to becoming endangered |
| nonrenewable resource | one that once use cannot be replace eg, fossil fuels or metals |
