The black furry rabbit, heterozygous for both traits, is crossed with a white smooth rabbit.

The black furry rabbit, heterozygous for both traits, is crossed with a white smooth rabbit. Make a crossing scheme and determine the genotypes of the offspring from crossing a black smooth rabbit, heterozygous for the first trait, with a smooth-haired white rabbit homozygous for both traits. What is the law of genetics manifested in this case?

Let’s designate the gene that causes the black color of the rabbit fur as A, then the gene for white fur will be a. The designation of the black fur gene by a capital letter can be explained by the phenotypic realization of this very trait in the black rabbit, which, according to the condition of the problem, is heterozygous for it (Aa).

Let’s designate the gene that causes the development of shaggy hair as C, then the gene for smooth hair will be c. Let us explain this also by the heterozygosity of the hairy rabbit genotype from the condition (Cc).

A black hairy, diheterozygous rabbit would be AaCc.

A black smooth rabbit, heterozygous for coat color, will be Aass, it will produce spermatozoa Ac and ac.

The white smooth rabbit will be aacc, because such traits have a chance to be phenotypically realized only in conditions of homozygous representation in the genotype. The rabbit produces oocytes ac.

From crossing such rabbits, we get the following offspring options:

black smooth rabbits (Ааcc) – 50%;

white smooth rabbits (aacc) – 50%.

This problem demonstrates the law of independent inheritance.