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Ecology
ecology
Question | Answer |
---|---|
ecology - | study of interactions of organism with other organisms and with the physical environment |
habitat - | place where an organ lives |
population - | organisms within an area belonging to the same species |
community - | consists of all the various populations interacting at a location |
ecosystem - | contains a community of populations and also, the abiotic environment |
biosphere - | zones of the earth's soil, water, and air where living organisms are found |
modern ecology describes and ________ | predicts distribution of an abundance of organisms |
population density - | number of individuals per unit area or volume. |
population distribution - | pattern of dispersal of individuals within the area of interest |
limiting factors - | factors that determine whether an organism can live in an area |
population size - | number of individuals contributing to the gene pool. |
intrinsic rate of natural increase - | allows us to calculate the growth and size of a population (births/deaths; immigration/emigratoin) |
discrete breeding - | they only have one reproductive event in their life (insects / annual plants) |
continuous breeding - | their entire lifes, they continue to invest energy in reproducing again (vertebrates, bushes, trees) |
exponential growth - | when reproduction accelerates |
biotic potential - | the maximum population growth that can possibly occur under ideal circumstances |
environmental resistance - | environmental conditions that prevent populations from achieving biotic potential (no food, predators) |
logistic growth - | growth when considering environmental resistance |
carrying capacity of an environment is _________ | maximum number of individuals of a given species the environment can support |
cohort - | all the members of a population born at the same time |
survivorship - | the probability of newborns of a cohort surviving to a particular age |
a population contains 3 major age groups: ________,_______, and ______. | prereproductive, reproductive, postreproductive |
density independent factors - | abiotic factors such as weather and natural disasters (# of organisms present does not influence the effect of the factor) |
density dependent factors - | biotic factor such as parasitism, competition, predation. |
r strategy - | produce large numbers of offspring when young (many offspring, little parental care) |
k strategy - | produce few offspring, and lots of parental care |
equilibrium species - | (the k strategy) |
opportunistic species - | (the r strategy) |
doubling time - | length of time it takes for population size to double (approx 53 years for humans) |
more developed countries (mdc's) | North America and Europe, population growth low, good life |
less developed countries (ldc's) | latin america, africa, asia; population grows rapidly, poverty |
demographic transition - | decreased death rate followed by decreased birthrate |
ways to reduce expected increase in population - | 1. family planning programs (birth control) 2. educate to reduce desire for large families 3. delay onset of childbearing (early babies) |
zero population growth - | no increase in population size. |
replacement reproduction - | having 2 babies to replace the parents (will still increase population due to longer lives) |
environmental impact (e.i.) | (population size) x (resource consumption per capita) = pollution per unit of resource Used |
community - | an assemblage of populations interacting with one another within the same environment. |
the composition of a community is... | simply a listing of the various species in the community |
diversity of a community includes... | both A. species richness (# of species) and B. species evenness (the relative abundance of individuals of different species) |
individualistic model - | suggests that each population in a community is there because its own particular abiotic requirements are met by a particular habitat. |
interactive model - | communities are the highest level of organization (cell -> tissue -> organ -> organism -> population -> community |
modern ecologists support individualistic or interactive model? | individualistic |
community composition is composed of... | abiotic gradients( climate,inorganic nutrients) biotic interactions (organic food source) |