population genetics Flashcards
name the requirements of natural selection
variation in members
hereditary traits in offspring
individual traits must affect survival/fitness
define population genetics
study of allele frequencies in a population
define HWE
expected genotype frequencies given the allele frequencies
dominance alone doesnt change freq
does a dominant allele rise in frequence just because its domant?
NO
if P2+2PQ+Q2=1 does this mean the population is at HWE?
no
assumptions of hardy weinberg
large, randomly mating, diploid, sexual populations with no mutations, selection or migration
how can you detect selectrion or indreeding for exampe?
the genotype frequency willdiffer from whats expected in HWE
diturbing influences of HWE
non random mating assortive mating migration genetic drife selection
how does nonrandom mating impact HWE
inbreeding for example
reduced the heterozygosity over the genomeee
how does assortive mating affect HWE
also reduced the heterozygotsity
how can migration impact HWE
moves the population away from the equlibrium
how does genetic drift impact HWE
alleles fall and rise in freq or lose altogether
nornammly smaller populations lose diversity in conservaton and captive breeeding
what does selection do to HWE
against certain genotypes
moves the population away from the equlibrium
how do you calculate frequency
indivivuals divided by the totoal polulation
why does hardy weinbery equlobrium almost never happen in nature?
one rule is always being violated
how can you be sure a population is on HWE?
have to observe at least two generations
ifthe allel freqs are the same for both generations then the population is said to be in HWE
genetic locus
speific location of a gene or DNA sequence on a chromosomes
mutations at a locus generates new alleles
what kind of hypothesis is hardy weinber?
null hypothesis
if a population deviates from the HWE we can then learn more about evolution
