In rabbits, hair of normal length is dominant (B), short-recessive (b). In a rabbit with short hair

In rabbits, hair of normal length is dominant (B), short-recessive (b). In a rabbit with short hair, 7 rabbits were born – 4 short-haired and 3 with normal hair. Determine the genotype and phenotype of the father.

According to the condition of the problem, rabbits with short hair, like the rabbit herself, demonstrate an externally realized recessive trait, therefore, they are homozygous for it. Let’s write them bb.

Rabbit bb produces eggs of the same type b and is capable of transmitting only the gene that causes the development of short hair to the offspring.

To be the father of both short-haired and long-haired rabbits, a rabbit father must pass both types of genes to them: both B and b, therefore, he is a heterozygote Bb, which is outwardly manifested in the normal length of his coat.

Rabbits: Bb – 50%, normal coat length; bb – 50%, short coat.

Answer: the father rabbit is heterozygous (Bb), he has normal hair length.