Chapter 15: Ecology Flashcards
ecology
-study of interactions of organisms with their physical environment and with each other
population
-group of a species that are can interbreed and interact with each other
community
-all organisms in one area
ecosystem
-organisms and abiotic factors that they interact with
biosphere
-global ecosystem
size
-number of individuals in a population
density
-number of individuals per unit area
dispersion
-pattern of spacing of individuals within the are
biotic potential
-maximum rate at which a population could increase under ideal conditions
limiting factors
- factors that limit population growth
- density-dependent: factors that increase as population density increases (predation)
- density-independent: factors whose occurrence is unrelated to the population density (earthquakes)
species richness
-number of different species in a community
relative abundance
-contributes to species diversity
competitive exclusion principle
-two species can’t coexist in a community if they share the same niche (same role)
resource partitioning
-one species that is competing for a resource will evolve through natural selection to exploit different resources
character displacement
-divergence in body structure
aposematic coloration
-bright coloration that warns predators of possible poison
batesian mimicry
- copycat coloration in which one harmless animal mimics the coloration of one that is poisonous
- viceroy and monarch butterfly
mullerian mimicry
-two or more poisonous species resemble each other and gain advantage from their combined numbers
mutalism
-symbiotic relationship in which both organisms benefit
commensalism
-symbiotic relationship in which one organism benefits and the other is unaffected
gross primary productivity (GPP)
-amount of light energy converted to chemical energy by photosynthesis per unit time
net primary productivity (NPP)
-GPP minus energy used by primary producers during cellular respiration
food pyramid
-represent the interactions of organisms in a food chain from one trophic level to the next
food web
-interwoven food chains
dominant species
-most abundant (have the largest biomass)
keystone species
-exert major control over other species in a community
ecological succession
-sequential rebuilding of an ecosystem after a disaster
primary ecoloical succession
-soil building through introduction of pioneer organisms
secondary ecological succession
-occurs when the soil is still intact after a disaster
nitrogen-fixing bacteria
-convert free nitrogen to ammonium ion
acid rain
-caused by combustion of fossil fuels
greenhouse effet
- CO2 and water vapor in the atmosphere absorb and retain heat of Earth
- increased levels of atmospheric CO2 i because of global warming
