Chapter 20 - HWE

allele

copy of a gene

genetic drift

random change in allele frequency

gene flow

movement of alleles in and out of population

bottleneck effect

random event reduces diversity in small population size

founder's effect

small group breaks off from a larger group

P^2

homozygous dominant

q^2

homozygous recessive

2pq

heterozygous

p

frequency of p allele

q

frequency of q allele

HWE equation

p2 + 2pq + q2 = 1

HWE equation 2

p+q=1

homozygous dominant for no sickle cell

no sickle cell + vulnerable to malaria

heterozygous dominant for sickle cell

no malaria + protects against sickle cell

homozygous recessive for sickle cell

dies from sickle cell but protects against malaria

chi square is lower than critical value

insignificant, equillibrium

chi square is higher than critical value

significant, no equillibrium

p>.05

fatass, insignificant

p<.05

petite, significant