Module 2.1 Flashcards
What is genetic diversity
Genetic variation within species (eye colours, Tre crown shape)
what is biodiversity
general term refers to the variety and variability of life on earth (genetic diversity, species diversity, ecological diversity))
what is population
a randomly breeding group of individuals that is largely isolated from others
what is population genetics
the study of genetic variation within and among populations and its response to evolutionary forces over space and time
why is population genetics important?
1) individuals exist in communities
2) genotypes of individuals are largely determines by the gene pool of the population
3) genetic diversity is defined at the population level
how to calculate proportion of each genotype in a population
number of individuals with each genotype / total individuals sampled
f(BB) = 1/4
f(Bb) = 1/2
f(bb) = 1/4
Sum must be equal to 1
what is allele frequencies + formula
proportion of an allele at a particular locus (of a gene) in a population for a diploid organism
count of specific allele / (2 * total individuals samples)
f(B) = 0.5
f(b) = 0.5
sum = 1
Hardy Weinberg principle
allele and genotype frequencies within a population will remain constant from generation to generation in the absence of other evolutionary forces
when these conditions are met, the population is said to be in hardy Weinberg equilibrium
what is the hardy Weinberg formula
p^2 + 2pq + q^2 = 1
p,q = allele frequencies
when allele frequencies are changed, the equilibrium will be reached again after one generation random mating
p+q=1
what is the proportion of heterozygosity in hardy Weinberg
2pq
what is the frequency of dominant in hardy Weinberg
p^2
what is the frequency of recessive in hardy Weinberg
q^2
what is heterozygosity
the proportion of heterozygotes for a particular locus
what is gene diversity
the proportion of polymorphic loci across genome
assumptions for HW principle
slide
what are the evolutionary forces
mutation
selection
gene flow (migration)
genetic drift (random effect)
what is mutation
source of all genetic variation
three ingredients for evolution by Darwin
variation, heredity, selection
what is point mutation
changes in one or a few nucleotides
how does mutation occur
point mutation, insertion/deletion
mutation rate in humans
1.0 - 1.5 x 10^-8
30 new DNA variants with each gamete
are most mutations good?
no, most are neutral or harmful
beneficial are rare
what is selection force
climate, predator, selective breeding
what is gene flow
movement of genes between population with gametes (pollen), individuals (seeds)
what are effects of gene flow
slides
what is genetic drift
change in allele frequency in a population from generation to generation due to random sampling
bottleneck effect
slides
effect of genetic drift
slides
