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Ch. 21 7th Grade

Populations and Communities

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
Created by: SSmith01