MBG 3060 (questions with complete
solutions)
qualitative traits - correct answer ✔✔specific phenotype directly associated w/specific
genotype
ex. coat color, HYPP
quantitative trait - correct answer ✔✔trait we can measure, controlled by many loci, slow
selection progress bc unable to identify one good genotype ex. milk yield, conformation
additive genetic component (A) - correct answer ✔✔measure of sum of effects of individual
alleles
genes working together
dominance genetic component (D) - correct answer ✔✔measure of combined dominance
effects of individual loci
interaction genetic component (I) - correct answer ✔✔measure of combined interactions b/w
loci
epistasis
σP2 - correct answer ✔✔phenotypic variance
= σG2+σE2
σG2 - correct answer ✔✔genotypic variance
= σA2+σD2+σ2
, σA2 - correct answer ✔✔additive genetic variance
σD2 - correct answer ✔✔dominance genetic variance
h^2 - correct answer ✔✔heritability
measures proportion of total variation that is addtive geentic variation
indicates degree of genetic resemblance b/w relatives and generations
helps define how much genetic change would result from selection
R and how to increase? - correct answer ✔✔response to selection
=Sh^2
can be increased by increasing selection (fewer individuals, inbreeding concern) or heritability
(measure phenotype more precisely, reduce σE2 bc equal to error in stats ex. if measuring how
tall horse is, depends on when farrier was last in, if on level ground, etc.)
generation interval for cattle - correct answer ✔✔4-7 years
generation interval for poultry - correct answer ✔✔<1 year
generation interval for pigs - correct answer ✔✔1-2 years
generation interval for humans - correct answer ✔✔25-35 years
realized heritability - correct answer ✔✔cumulative R/cumulative S
solutions)
qualitative traits - correct answer ✔✔specific phenotype directly associated w/specific
genotype
ex. coat color, HYPP
quantitative trait - correct answer ✔✔trait we can measure, controlled by many loci, slow
selection progress bc unable to identify one good genotype ex. milk yield, conformation
additive genetic component (A) - correct answer ✔✔measure of sum of effects of individual
alleles
genes working together
dominance genetic component (D) - correct answer ✔✔measure of combined dominance
effects of individual loci
interaction genetic component (I) - correct answer ✔✔measure of combined interactions b/w
loci
epistasis
σP2 - correct answer ✔✔phenotypic variance
= σG2+σE2
σG2 - correct answer ✔✔genotypic variance
= σA2+σD2+σ2
, σA2 - correct answer ✔✔additive genetic variance
σD2 - correct answer ✔✔dominance genetic variance
h^2 - correct answer ✔✔heritability
measures proportion of total variation that is addtive geentic variation
indicates degree of genetic resemblance b/w relatives and generations
helps define how much genetic change would result from selection
R and how to increase? - correct answer ✔✔response to selection
=Sh^2
can be increased by increasing selection (fewer individuals, inbreeding concern) or heritability
(measure phenotype more precisely, reduce σE2 bc equal to error in stats ex. if measuring how
tall horse is, depends on when farrier was last in, if on level ground, etc.)
generation interval for cattle - correct answer ✔✔4-7 years
generation interval for poultry - correct answer ✔✔<1 year
generation interval for pigs - correct answer ✔✔1-2 years
generation interval for humans - correct answer ✔✔25-35 years
realized heritability - correct answer ✔✔cumulative R/cumulative S
