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Chapter 18 bio vocab

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ecology
the study of the interactions between organisms and their environment
Abiotic factors
consists of nonliving chemical and physical factors
Biotic factors
consists of living factors- all the other organisms that are part of an individual's environment
organismal ecology
the study of evolutionary adaptations that enable individual organisms to meet the challenges posed by their abiotic environments
population
a group of interacting individuals belonging to one species and living in the same geographic area
population ecology
the study of how members of a population interact with their environment, focusing on factors that influence population density and growth
community
consists of all the organisms that inhabit a particular area
community ecology
the study of how interactions between species affect community structure and organization
ecosystem
all the organisms in a given area, along with the nonliving factors with which they interact
ecosystem ecology
the study of energy flow and the cycling of chemicals among the various biotic and abiotic factors in an ecosystem
bioshpere
the global ecosystem; that portion of each that is alive
habitats
specific environments in which organisms live
abiotic factors of the biosphere
water, sunlight, temperature, wind, rocks and soil, periodic disturbances, and physiological responses
acclimation
physiological response that is longer term, though still reversible
population density
the number of individuals of a species per unit area or volume
mark-recapture method
a sampling technique used to estimate wildlife populations
dispersion pattern
the way individuals are spaced within the population's geographic range
clumping
due to unequal distribution of resources
uniform
results from interactions among the individuals of a population
random dispersion
individuals in a population are spaced in a patternless, unpredictable way
growth rate
the change in population size per time interval
exponential growth model
the whole population multiplies by a constant factor during constant time intervals
population-limiting factors
environmental factors that restrict population growth
logistic growth model
a description of idealized population growth that is slowed by limiting factors
carrying capacity
the number of individuals in a population that the environment can just maintain with no net increase or decrease
intraspecific competition
competition between individuals of the same species for a limited resource
density-dependent factor
a population-limiting factor whose effects intensity as the population increases in density
age structure
the proportion of individuals in different age-groups
life history
the series of events from birth through reproduction and death
life table
tracks survivorship and mortality in population
survivorship curve
a plot of people still alive at each age
Type I
flat, steady, drops steeply in old age death
Type II
mortality constant over life span
Type III
indicates high death rates for the very young and then a period when death rates are very low for survivors of a certain age
opportunistic life history
the pattern of reproducing when young and producing many offspring
equilibrial life history
generally results in a type I survivorship curve; mature later and produce few offspring but care for their young