Question

In guinea pigs, the color of the fur is determined by a single gene with two alleles control. The brown allele (B) is dominant over the white allele (b). Two heterozygous guinea pigs are crossed. Draw a genetic diagram with the genotypic, phenotypic and ratio information of the P₁ and F ₁ generations of this cross.​

Answer 1

See

Step-by-step explanation:

Given:

Brown allele (B) is dominant over the white allele (b).

It will be assumed that the alleles are not related to the X and Y chromosomes.

See attached diagram for details of the general case (for both homo-zygous and hetero-zygous parents)

For both parents hetero-zygous,

P1:

Genotype: Bb (100%)

Phenotype: brown (100%)

F1:

Genotypes : BB, Bb, bB and bb in equal proportions, i.e.

BB (25%), Bb (50%), bb (25%)

Phenotypes: 75% brown (from BB and Bb), 25% white (from bb)