1) Which of the following scenarios best describes an epistatic gene?
a. Fur pattern is controlled by two genes such that one gene inhibits the expression of the other gene.
b. Mouse fur colours are expressed as a blend of the dominant black colour and the recessive white colour, resulting in a heterozygous brown colour.
c. Individuals with sickle cell anemia and carriers of the sickle cell allele have some resistance to malaria.
d. Chicken combs follow a dominance hierarchy whereby a walnut comb is the most dominant and a single comb is the least dominant.
2) SEE IMAGE ATTACHED PLEASE
3) If the P1 generation is a rose comb (RRpp) crossed with a pea comb (rrPP), which of the following represents the correct genotype and phenotype of the F1 offspring?
a. Genotype Phenotype
RrPp pea comb
b. Genotype Phenotype
RrPp walnut comb
c. Genotype Phenotype
RRPP walnut comb
d. Genotype Phenotype
RRPP Single comb
4) Which of the following represents the correct phenotypes of the F2 offspring?
a. Phenotype
Single Walnut Pea Rose
1 / 16 9 / 16 3 / 16 3 / 16
b. Phenotype
Single Walnut Pea Rose
3 / 16 1 / 16 9 / 16 3 / 16
c. Phenotype
Single Walnut Pea Rose
3 / 16 9 / 16 1/ 16 3 / 16
d. Phenotype
Single Walnut Pea Rose
9 / 16 3 / 16 3 / 16 1 / 16
5) The Labrador Retriever’s coat colours are black, yellow, and chocolate.
Yellow is produced by the presence of a recessive epistatic gene, which has the effect of masking the black and chocolate colour genes. Black (B) is dominant to chocolate (b).
Therefore, the possible genotypes and corresponding phenotypes are:
Phenotype Possible Genotypes
Black G__B__
Brown G__bb
Yellow gg__
Predict the percentage of offspring that would be black in colour for each of the following crosses. Record your answer as a whole number.
Cross: GgBb X GgBB GGBb X GGBb
Percentage
of
Offspring: Answer % Answer %
6) SEE IMAGE TWO ATTACHED PLEASE