evol bio exam 2

mutation

any change in the genomic sequence within an organism

mutation

the ultimate sure of genetic variation caused by external source (radiation) or an error

what are processes of evolution

• mutation

• drift

• natural selection

• migration

genome

all DNA that an organism has

allele

version of a gene at a locus

locus

spot/place on chromosome, “gene”

point mutation

single base pair changing to another base pair

most frequent type of mutation

point mutation

insertion

3 base pairs get added

deletion

3 base pairs get deleted

gene duplication

whole gene gets deleted

genome duplication

whole genome gets fully duplicated

inversion

gene order gets changed around

fusion

2 chromosomes get fused into 1

synonymous

encoded the same amino acid

no change in sequence

non synonymous

new codon that changes sequence

nonsense

the new codon is changed to a stop codon (premature termination of translation)

in frame (insertion or deletion)

• deletion or addition in the same codon

• it has to be exactly 3 base pairs removed

frame shift mutation

deletion or addition in more or less than 3 base pairs

lethal mutation

less than 1

beneficial mutation

higher than 1

frequency

# of things in the same category/total # of things

f(A1)=

p= 1-q

f(A2)=

q= 1-p

p+q=

1

hardy weinburg equilibrium

allele and genotype frequencies don’t predominately rely on mendelian ratios

both published work at same time

hardy weinburg equilibrium

allele and genotype frequencies in a population will remain constant from generation to generation with the absence of evolutionary influences

what is the mendelian phenotype ratio

3:1 (two heterozygotes with dominant trait)

what is the mendelian genotype ratio

1:2:1 (assuming random mating)

w

fitness

average fitness equation

w̄ = p2w11 + 2pqw12 + q2w22

a1a1

p2

a1a2

2pq

a2a2

q2

change in p equation

p = (p2w11 + pqw12) / w̄

what are the natural selection conditions

• variation (differences in phenotype)

• fitness differences

• heritability

haldane sieve

dominant (or partially) allele have a much greater contribution to adaptation that recessive alleles

founder effect

diversity in larger population

• new population started by a small number of individuals

probability of eventually fixing an allele

p

probability of eventually losing an allele

1-p

cline

region of polymorphism maintained migration

• selection balanced

best genotype

1

worst genotype

1-s

allele frequencies & genotypes will not change when what occurs

• random mating (no inbreeding or geographic structure)

• genotypes don’t differ (no selection)

• no mutation

• no migration

• no drift

stochastic

random

Vp

phenotypic variance

Vg

genetic variance

Ve

environmental variance

equation for phenotypic variance

Vp = Vg + Ve

equation for genetic variance

Vg = Va + Vd + Vi

Va

additive genetic variance

Vd

dominance genetic variance

Vi

epistatic (interaction) genetic variance

additive genetic variance

due to alleles

dominance genetic variance

interactions between alleles at a locus

epistatic genetic variance

interactions across loci

genetic drift

allele frequency change due to sampling that is caused by a finite population size (probability in each generation)

var (change in p) =

pq / 2n

small population is equal to

more variation

E (p’) =

p

E (change in p) =

0

drift

no direction

• depends on current allele frequency & population size

• more likely to lose rare alleles

dominant equation

q̂ = ų/s

recessive equation

q̂ = sqrt (ų/s)

additive equation

q̂ = 2ų/ s

incomplete dominance

q̂ = ų/hs

ų

mutation rate

s

selection coefficient

q̂

equilibrium frequency

Pe =

p2

He =

2pq

Qe =

q2

p =

Po + 1/2(Ho)

what is the dominant equation

balance between new mutation and removal

what is the recessive equation

balance between new mutation & retention of all mutations vs. removal (homozygotes)

probability of eventual mutations

p

p(initial) =

1/2N

equation for probability that allele will be lost

1-p(initial) = (2N-1) / 2N

bottleneck effect

a sharp drop in the size of a population caused by a random event that leaves behind only a small, non-representative group of survivors

types of mutations

• dominant

• recessive

• additive

• imcompletely dominant

deletarious mutations

a genetic alteration that reduces an individual's reproductive fitness or increases their susceptibility and predisposition to a genetic disorder

what is higher, base pair mutations or deletarious mutations?

deletarious mutations

broad sense heritability

measures the proportion of total phenotypic variance explained by all types of genetic variation combined

narrow sense heritability

proportion of phenotypic variance explained only by additive genetic variance

• causes evolutionary change

narrow sense heritability equation

h2 =Va/Vp

broad sense heritability equation

H2 =Vg/Vp

parent offspring regression

measure how much a physical trait (like height, weight, or milk production) is passed down from parents to their children

half sibling breeding design

a controlled mating system where half-siblings (animals sharing one parent but having different parents of the opposite sex) are bred together

R

response to selection

h

heritability

s

selection differential

how to get h2 from parent offspring regression

h2 =R/s

z̄

mean

z̄0

mean of offspring of selected parents

how to get response to selection (R)

R = z̄0 - z̄

how to get selection differential

s = z̄s - z̄

incomplete dominance has what dominance parameter

h in w12

additivity

a type of gene action where multiple genes or alleles contribute to a physical trait (phenotype) as the direct sum of their individual effects, without dominance or masking interactions

additivity w12

1-1/2s

incomplete dominance w12

1-hs