| A | B |
|---|
| biotic factors | living influences on organisms within an ecosystem |
| abiotic factors | nonliving factors that shape ecosystems |
| habitat | the area where an organism lives |
| niche | an organism's role within the ecosystem; what an organism does to survive |
| competitive exclusion principle | states that no two species can occupy the same niche in the same habitat at the same time |
| predation | an interaction in which one organism captures and feeds on another organism |
| mutualism | both organisms benefit from the relationship |
| parasitism | one organims live on or inside another organism and harms it |
| commensalism | one organism benfits from the relationship and the other is neither helped nor harmed |
| ecological succession | series of predictable changes that occur in a community over time |
| primary succession | succession that occurs on surfaces where no soil exists |
| secondary succession | succession that occurs after a disturbance that destroys a community without destroying the soil |
| pioneer species | the first species to populate an area |
| climax community | a mature community |
| symbiosis | an relationship in which two organisms live closely together |
