Question

If you assume that the black alleles (red items) are dominant and the brown alleles (white items) are recessive traits, what would be the ratio of black rabbits to brown rabbits among the offspring of two rabbits with heterozygous genotypes?

A) 1:2
B) 2:1
C) 3:1
D) 1:1

Answer 1

The ratio of black rabbits to brown rabbits among the offspring of two rabbits with heterozygous genotypes would be 2:1.

Step-by-step explanation:

The ratio of black rabbits to brown rabbits among the offspring of two rabbits with heterozygous genotypes can be determined using a Punnett square. The genotypes of the parents would be Bb, where B represents the black allele and b represents the brown allele. When these genotypes are crossed, the possible genotypes of the offspring would be BB, Bb, and bb. Among these, the black rabbits would have the genotypes BB and Bb, while the brown rabbits would have the genotype bb.

Since the black allele is dominant, a rabbit with either BB or Bb genotype would have a black coat. Therefore, the ratio of black rabbits to brown rabbits would be determined by the ratio of BB:Bb:bb genotypes. In this case, the ratio would be 2:1, meaning there would be twice as many black rabbits as brown rabbits among the offspring.