| A | B |
|---|
| fossil fuel | An energy source formed from the buried remains of decayed plants and animals that lived hundreds of millions of years ago. |
| natural resource | Materials from the environment that people used to carry on their daily lives. |
| renewable resource | A natural resource, such as trees or soil, that can be replaced by natural cycles or processes. |
| biomass energy | Energy that is released when plants and plant products are burned. |
| nuclear energy | Energy released by either the splitting apart or the joining together of atoms of certain elements. |
| solar energy | Energy from the sun |
| nonrenewable resource | A natural resource, such as oil or natural gas, that cannot be replaced by natural processes. |
| geothermal energy | Energy that comes from heat from the earth’s hot interior. |
| smog | Air pollution caused by automobile exhaust, or burning coal, or by other mans, resulting in air that is unhealthy to breathe. |
| acid rain | Highly acidic droplets formed when gases produced by the burning of fossil fuels combines with moisture in the clouds. |
| hazardous waste | Waste substances that are very harmful to humans and other organisms. |
