In the yawncat (a rare hypothetical animal), the dominant allele R causes solid tail color, and the recessive allele r results in white spots on a colored background. The black coat color allele B is dominant to the brown allele b, but the B and b alleles can only be expressed if the animal has an mm genotype at a third gene locus. Animals that are M_ are yellow regardless of which allele from the B locus is present. A mating between a solid yellow-tailed male yawncat and a solid brown-tailed female yawncat produces 16 offspring with the following tail phenotypes: six solid yellow, two spotted yellow, three solid black, one spotted black, three solid brown, and one spotted brown.
- What is the MOST likely genotype of the male parent?
A) MM BB RR
B) MM Bb RR
C) Mm Bb RR
D) Mm BB Rr
E) Mm Bb Rr

Question

Quizplus · Accepted Answer

The male parent must be Mm to produce yellow offspring and Bb to produce both black and brown offspring. The presence of spotted offspring indicates he must also carry the recessive r allele, making him Rr.

In the Yawncat (A Rare Hypothetical Animal), the Dominant Allele