click below
click below
Normal Size Small Size show me how
Ch. 21 7th Grade
Populations and Communities
| Term | Definition |
|---|---|
| biosphere | parts of the Earth and the atmosphere where there is life |
| biotic potential | potential growth of a population in perfect conditions with no limiting factors |
| carrying capacity | largest number of individuals of one species that an environment can support |
| competition | struggle in a community for the same resources |
| limiting factor | anything that restricts the size of a population |
| population | all the organisms of the same species that live in the same area at the same time |
| population density | size of a population compared to the amount of space available |
| birthrate | number of offspring produced over a given time period |
| death rate | number of individuals that die over a given time period |
| endangered species | population that is at risk of extinction |
| estimate | to determine roughly the size, nature, or extent of something |
| exponential | mathematical expression that contains a constant raised to a power |
| extinct species | population that has died out |
| migration | instinctive seasonal movement of a population |
| threatened species | population at risk but is not yet endangered |
| commensalism | symbiotic relationship that benefits one species but does not harm or benefit the other |
| consumer | organism that gets energy by eating other organisms |
| habitat | place within an ecosystem where an organism lives |
| mutualism | symbiotic relationship in which both partners benefit |
| niche | what a species does in its habitat to survive |
| parasitism | symbiotic relationship that benefits one species and harms the other |
| predator | organism that gets energy from making its own food |
| symbiosis | close, long-term relationship between two species that usually involves exchange of food and energy |