| A | B |
|---|
| autotrophs | use sun for energy |
| producer | can produce food |
| photosynthesis | use light energy to power chemical reaction |
| chemosynthesis | use chemical energy to produce carbohydrates |
| heterotrophs | obtains energy from the foods it consumes |
| consumer | relies on other organisms for its energy and food supply |
| herbivore | obtains energy by eating only plants |
| omnivore | obtains energy by eating both plants and animals |
| decomposer | breaks down and obtains energy from dead organic matter |
| food chain | series of steps in an ecosystem in which organisms transfer energy by eating and being eaten |
| food web | network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem |
| trophic level | step in a food chain or food web |
| ecological pyramid | diagram that shows the relative amounts of energy |
| biomass | total amount of living tissue within a given trophic level |
| evaporation | process by which water changes from a liquid into an atmospheric gas |
| transpiration | water leaves plant |
| nutrient | chemical substance that an organism requires to live |
| nitrogen fixation | process of converting nitrogen gas into ammonia |
| biotic factors | biological in fluence on organisms within an ecosystem |
| abiotic factors | physical, or nonliving, factor that shapes an ecosystem |
| niche | the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. |
| predation | interaction in which one organism captures and feeds on another organism |
| symbiosis | relationship in which two species live closely together |
| mutualism | symbiotic relationship in which both species benefit from the relationship |
| commensalisms | symbiotic relationship in which one member of the association benefits andthe other is neither helped nor harmed |
| parasitism | symbiotic relationship in which one organism lives in or on another organism and harms it |
| deforestation | loss of forests |
