What offspring will result from crossing a hornless, black bull (heterozygous in both traits)

What offspring will result from crossing a hornless, black bull (heterozygous in both traits) with a horned red cow, if hornless and black are the dominant traits?

Let’s designate the hornless gene as A, then the gene that determines the development of horns will be a.

Let’s designate the gene that determines the black color of the cows’ coat as B, then the gene for the red suit will be b.

The diheterozygous black hornless bull is AaBb, it produces spermatozoa AB, ab, Ab and aB.

The red horned cow is aavb, since homozygosity is a condition necessary for the phenotypic realization of a recessive trait. Her eggs are av.

The offspring of this pair are represented by the following options:

black hornless calves (AaBb) – 25%;

red horned calves (aabb) – 25%;

black horned calves (Aabb) – 25%;

red hornless calves (aaBb) – 25%.