In guinea pigs, disheveled (rosette) hair dominates over smooth, and black over white. when a black

In guinea pigs, disheveled (rosette) hair dominates over smooth, and black over white. when a black rosette female was crossed with a smooth white male, offspring were obtained, half of which consisted of white rosette individuals. determine the genotypes of the female and a known part of the offspring

Let us designate the gene that causes the development of rosette hair type in guinea pigs as C, and the gene for smooth hair as c.

Let’s designate the gene that leads to the development of black wool in guinea pigs as P, then the gene for white wool will be designated as p.

A smooth white male will be dihomozygous because recessive genes are phenotypically realized only if the individual’s genotype is homozygous for them. The male ssrr will produce the same type of spermatozoa cp and transmit only genes for recessive traits to the offspring.

Consequently, cubs with white rosette hair will be heterozygous for the gene for the first trait, receiving the dominant rosette hair gene from the parental female with rosette hair.

Cubs have the Ссрр genotype. Since they have a black coat color due to the homozygosity of their genotype for the black coat gene – pp, it should be concluded that white females are heterozygous for the color gene.

Female guinea pigs, therefore, must have the genotype CCPp, or CcPp.

It is not possible to finally determine the genotype of black females with rosette hair, since the genotypes of the second half of the offspring are unknown.

Answer: calves – Ссрр, females – СсРр / СсРр