In a certain dog breed, the allele B for a black coat is dominant, and the allele b for a spotted coat is recessive. What genotypes for this dog breed would lead to a spotted phenotype? **Make a Punnet square for help**(1 point)

Responses

BB

Bb

BB and bb

bb

1 answer

In the given scenario, the allele B (black coat) is dominant, and the allele b (spotted coat) is recessive. For a dog to exhibit a spotted phenotype, it must have the genotype that expresses the recessive trait, which is "bb."

Here's a simple Punnett square to demonstrate the possible genotypes from a cross. Assuming we are looking at a cross between a homozygous recessive (bb) dog and a heterozygous (Bb) dog:

         B     |     b
       ----------------
    b |    Bb   |    bb
       ----------------
    b |    Bb   |    bb

From the Punnett square:

  • 50% of the offspring will be Bb (black coat)
  • 50% of the offspring will be bb (spotted coat)

Thus, only the genotype "bb" leads to a spotted phenotype.

Answer:

The genotypes for this dog breed that would lead to a spotted phenotype is bb.