A yellow guinea pig, when crossed with a white one, produces cream offspring.
A yellow guinea pig, when crossed with a white one, produces cream offspring. Crossing cream-colored pigs with each other gave 26 yellow, 22 white and 50 cream. Why? Determine the genotypes of all family members.
From the condition of the problem, it should be concluded that the inheritance of the hair color of guinea pigs is intermediate, which means the appearance of a third, usually intermediate in quality, trait (cream wool) in heterozygotes compared to homozygotes for a dominant or recessive gene (with yellow or white animals) …
Let’s designate the gene that causes the yellow color of the guinea pig’s fur as C, then the gene for white wool will be designated as c.
Guinea pigs with cream-colored coats will have a heterozygous genotype – Cc.
These guinea pigs produce two types of germ cells – C and c. When crossing them among themselves, splitting will be observed in the offspring. The offspring will be represented by the following theoretically possible options:
heterozygous cubs with cream hair (Cc) – 50%;
homozygous young with yellow hair (CC) – 25%;
homozygous cubs with white hair (cc) – 25%.