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unit 4 biology

unit 4 ecosystems stability and change

measurements of the number of individuals living in a defined space population density
how a population is spread in an area population dispersion
individuals gather into groups where resources are available (ex. fish) clumped
what affects population growth births, deaths, migration, limiting factors
population size increases dramatically over a relatively short period of time exponential growth
population begins with a period of slow growth followed by a period of exponential growth before leveling off at a stable size logisitics growth
competition, disease, and over crowding density dependent
natural disaster density independent
amount of organisms an ecosystem can support carrying capacity
what would happen if a carrying capacity exceeded organisms die because lack of resources
completely destroyed (ice age, mass volcanoes) primary succession
partly destroyed and can come back relatively soon (flood, fire) secondary succession
first species to occupy an area pioneer species
a specific place or role for an organism in an ecosystem niche
2 species cannot share the same niche in the same __________ habitat
causes species to divide resources competition
organisms feed on one another predation
the hunter predator
one who is getting eaten prey
a species that can change an ecosystem dramatically keystone species
when organisms from a relationship symbiosis
both species benefit mutualistic
one benefits and the other is not harmed or helped commensalism
one benefits, one harmed parasitism
bird on cows back a. commensalism b. mutualism c, parasitism mutualistic
tapeworms and humans a. parasitism b. commensalism c. mutualism parasitism
what are the 4 of the major 6 biomes desert, grassland, rain forest, tundra, taiga, deciduous
how much is lost between trophic levels 90%
Created by: agnann1