19 terms

Final 2012 - Modern Biology Chpt. 16-17 test pt. 1

dogwood trees in Middletown, Conn.
a description of a population
recombination of genes as a result of sexual reproduction
cause of variation in genotype
phenotype frequency
# of individuals w/ a particular phenotype divided by total # of individuals in the population
occurence of mutations, nonrandom mating, genetic drift
reasons proportions of homozygotes & heterozygots can differ from Hardy-Weinberg predictions
no mutations occur, population is infinitely large, individuals neither leave nor enter population
conditions required for Hardy-Weinberg genetic equilibrium
phenotypes that are expressed
what natural selection acts on
genetic drift, migration, nonrandom mating
conditions that can cause evolution to take place
movement of genes from one population to another
gene flow
small populations
type of populations most susceptible to loss of genetic variability as a result of genetic drift
directional selection
a change in frequency of a particular gene in 1 direction in a population
disruptive selection
type of selection that may eliminate intermediate phenotypes
one extreme in a range of phenotypes
what directional selection tends to eliminate
attract potential mates
reason large, brightly colored tail feathers of male peacock are valuable to him
there may be phenotypic variability in a species, organisms that can interbreed may have different physcial characteristics, does not consider whether individuals of a species can mate
reason for major limitations to morphological concept of species
populations that live in different environments may be exposed to different selection pressures
reason speciation can occur as a result of geographic isolation
hypothesis that evolution occurs at a slow, constant rate
punctuated equilibrium
the hypothesis that evolution occurs at an irregular rate through geologic time
the science of classifying living things
become more similar in appearance
this happens as organisms move through the biological hierarchy from kingdom to species level