| Flap 1 | Flap 2 |
| The flow of energy from one orginism to another is called what? | food chain |
| What do sewage treatment plants clean? | waste water |
| What process breaks down carbon compounds in the carbon dioxide-oxygen cycle? | cell respiration |
| What kind of consumers are humans? | omnivores |
| What is the process by which water vapor (gas) is changed into a liquid called? | condensation |
| Overlapping food chains form what? | food webs |
| When nitrogen is "fixed" what is it changed into? | nitrogen compounds |
| The process by which liquid water changes into water vapor is called what? | evaporation |
| What compound acts as the building blocks of living things? | proteins |
| In the nitrogen cycle, what is converted (changed) to a usable form? | nitrogen gas |
| During phytosynthesis plants give off what as a waste product? | oxygen |
| As plants decay they add________compounds to the air and soil. | carbon |
