Question

In mice, the allele for black fur is dominant to the allele for brown fur. A male homozygous black mouse is crossed with a female brown mouse, and the F1 offspring are allowed to breed. What percentage of F2 offsprings do you predict will be homozygous black mice?

Answer 1

25%

Step-by-step explanation:

Given that the allele for black fur is dominant to the allele for brown fur. A male homozygous black mouse (BB) is crossed with a female brown mouse (bb). The F1 progeny would have black fur with heterozygous dominant genotype (Bb).

Self crossing of F1 progeny would obtain the F2 progeny in following genotype ratio= 1/4 BB (homozygous black): 1/2 Bb (heterozygous black): 1/4 bb (homozygous brown).

Hence, 25% of the F2 progeny would be homozygous black.