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Chapter 21
Vocabulary
Term | Definition |
---|---|
biosphere | the parts of Earth and the surrounding atmosphere where there is life |
community | all the populations of different species that live together in the same area at the same time |
population | all the organisms of the same species that live in the same area at the same time |
competition | the demand for resources suck as food and water and shelter in short supply in a community |
limiting factor | anything the restricts the size of a population |
population density | the size of a population compared to the amount of space available |
biotic potential | the potential growth of a population if it could grow in perfect conditions with no limiting factors |
carrying capacity | the largest number of individuals of one species that an environment can support |
birthrate | the number of offspring produced of a given time period |
death rate | the number of individuals that die over the same time period |
extinct species | a species that had died out and no individuals are left |
endangered species | a species whose population is at risk of extinction |
threatened species | a species at risk but not yet endangered |
migration | the instinctive seasonal movement of a population of organisms from one place to another |
habitat | the place within an ecosystem where an organism lives |
niche | what a species does in its habitat to survive |
producers | organisms that get energy from the environment |
consumers | organisms that get energy by eating other organisms |
symbiosis | long term relationship between two species that usually an exchange of food and eneergy |
mutualism | a symbiotic relationship in which both partners benfit |
commensalism | a symbiotic relationship that befits one species but does not harm or benefit the other |
parasitism | a symbiotic relationship that benefits species and harms the other |