Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
30 Cards in this Set
- Front
- Back
|
what does HIV infect? |
helper T cells |
|
|
how does HIV inhibit immune function |
- Lyses helper T cells after infection - infected cells removed by killer T cells |
|
|
how are new alleles made? |
point-mutations from errors made by DNA polymerase |
|
|
What are the different origins of new genes? |
- gene duplication - overprinting - Insertions |
|
|
how does overprinting occur for creating a new gene? |
point mutations produce new start codons and create a new reading frame |
|
|
How is a new gene added by insertion? |
RNA is reversed transcribed and DNA inserted into genome |
|
|
how does gene duplication occur? |
- results from unequal crossovers - redundant copy called pseudogene |
|
|
what are the different chromosome alterations and how do they occur? |
- inversion: two breaks in chromosome and middle piece inverts - polyploidy: meiosis errors forming diploid gametes or mitosis errors |
|
|
what are the assumptions of HW equilibrium? |
- no selection - no migration - no mutations - large population - random mating |
|
|
what is inbreeding depression |
deleterious recessive alleles become more prominent |
|
|
what is linkage equilibrium and disequilibrium? |
LE: genotype at one locus independent of genotype at second locus
LD: do not assort independently |
|
|
how is linkage diseqm created? |
- physical linkage - Selection at multi-locus genotypes - genetic drift |
|
|
How can you tell if linkage diseqm is present? |
freq AA* freqBB not= freqAABB |
|
|
what reduces linkage diseqm? |
sexual reproduction |
|
|
how to calculate freq(AB) in the next generation (freq(AB')) in a two locus HW |
freq=g
g(AB')=gAB-r(gAB*gab)-(gaB*gAb) = gAB -rD
r=recomb. rate |
|
|
How do you calculate the coefficient of diseqm |
D=coeff. of diseqm D=(gAB*gab)-(gAb*gaB) D=0 when no LD |
|
|
if a population is in linkage eqm, what does gAB equal to in two locus HW |
gAB=p*s p=freq(A) s=freq(B) |
|
|
Why is sexual preferred over asexual for females since energy is costly and and would pass 100% of genes on? |
- allows for adaptation to selection forces - reduces genetic linkage -- if deleterious mutation present, not all offspring receive it through sexual - if mother not adapted to new conditions, asexual offspring wouldn't do well |
|
|
what is a quantitative trait? |
a trait that shows continuous variation |
|
|
how do you calculate heritability? |
heritability=h^2
h^2=Vg/Vp
Vg=genetic variation
Vp=total phenotypic variation |
|
|
how do you calculate total phenotypic variation? |
total phenotypic variation=Vp
Vp=Vg + Ve
Vg=genetic var
Ve=enviro var |
|
|
what is broad sense vs narrow sense heritability? |
broad sense: H^2=Vg/Vp narrow sense: ratio of additive genetic variance to total phenotypic variance |
|
|
How do you measure selection? |
Selection differential = S = difference between before and after selection S=P* - P |
|
|
how do you calculate response to selection? |
Response = R
R=h^2*S R= O* - O |
|
|
in selection calculations, what does heritability equal to in relation to S and R and what does the heritability mean? |
H^2=R/S = (O*-O)/(P*-P)
H^2 is the slope |
|
|
what are the types of selection? |
- stabilizing - directional - disruptive |
|
|
what is phenotypic plasticity? |
you get different phenotypes depending on the environment |
|
|
What maintains genetic variation? |
- mutation - heterozygote advantage - freq. dependent selection - gene flow - environmental heterogeneity |
|
|
what are darwin's postulates? |
- individuals within a species are variable - some variations are passed to offspring - more offspring are produced than survive - survival and repro are non-random |
|
|
what is adaptation vs evolution? |
adaptation: genetically based trait that increases fitness relative to others without the trait evolution: change in allele freq. in a pop over time |
