Lecture 20: Population Genetics Flashcards
population
group of individuals with gene flow
Hardy-Weinberg Equilibrium
allows for calculation of allele and genotype frequencies
what does “p” represent?
frequency of dominant allele in a population
what does “q” represent?
frequency of recessive allele in a population
what equation is used to calculate allele frequencies?
p + q = 1
what represents homozygous dominant?
p^2
what represents homozygous recessive?
q^2
what represents heterozygous
2pq
what is the diploid genotype equation?
p^2 + 2pq + q^2 = 1
What are the 5 mechanisms of evolution?
- Natural selection 2. gene flow 3. mutation 4. nonrandom mating 5. genetic drift
what are the 3 types of selection for natural selection?
- stabilizing selection 2. disruptive selection 3. directional selection
stabilizing selection
keeps population the same where you select from the middle and against the extremes
disruptive selection
select for the extremes at the expense of the middle; involved in speciation
directional selection
select for one end of the distribution at the expense of the other
gene flow
movement of alleles in or out of a population; changes in allele frequencies ex: migration
Nonrandom mating
when a person prefers a mate; geographic, location
mutation
any random change in a sequence; ultimate source of variation
genetic drift
random changes in allele frequency leads to a smaller population; decrease in variation
founder effect
have a big population and then a little group leaves; will experience genetic drift–>decrease in variation
bottleneck effect
big population that gets small quickly; lose variation; survival is random
