Two genes interact to produce various phenotypic ratios amon

Two genes interact to produce various phenotypic ratios among F2 progeny of a dihybrid cross. Design a different pathway explaining each of the F2 ratios below, using hypothetical genes R and T and assuming that the dominant allele at each locus catalyzes a different reaction or performs an action leading to pigment production. The recessive allele at each locus is null (loss-of-function). Begin each pathway with a colorless precursor that produces a white or albino phenotype if it is unmodified. The ratios are for F2 progeny produced by crossing wild-type F1 organisms with the genotype RrTt.

- Its a multiple choice question, this section goes up to Part G, but the next question will not appear after finishing Part C.

Question:

Part C. 9/16 green : 3/16 yellow : 3/16 blue : 1/16 white

Select one of these options:

* At least one copy of both dominant alleles in homozygous condition results in green. The first recessive allele functions as a suppressor of the second; therefore the result is yellow. The second recessive allele functions as a suppressor of the first; therefore, the result is blue. If both recessive alleles are present, it will produce white.

* At least one copy of both dominant alleles results in green, at least one copy of one dominant allele results in yellow, at least one copy of the other dominant allele results in blue, and the absence of either dominant allele results in white.

* At least one copy of both dominant alleles results in white, at least one copy of one dominant allele results in yellow, at least one copy of the other dominant allele results in blue, and the absence of either dominant allele results in green.

Solution

Answer:

At least one copy of both dominant alleles results in green, at least one copy of one dominant allele results in yellow, at least one copy of the other dominant allele results in blue, and the absence of either dominant allele results in white.

Explanation:

R_T_ = Green

R_ tt = yellow

rrT_ = blue

rrtt = white or albino