In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If two black, solid dogs were crossed several times and the total offspring were eighteen black, solid and five black, spotted puppies, the genotypes of the parents would most likely be
A) Bb Ss x Bb Ss .
B) Bb Ss x Bb SS .
C) BB Ss x Bb ss .
D) BB Ss x Bb Ss .
E) Bb ss x Bb SS .

Question

Quizplus · Accepted Answer

The parents must be heterozygous for coat color (Bb) to produce both black and red offspring. They must also be heterozygous for solid color (Ss) to produce both solid and spotted offspring. The only genotype combination that meets these requirements is BB Ss x Bb Ss.

In Cocker Spaniels, Black Coat Color (B) Is Dominant Over