If a red cow (homozygous dominant) is crossed with a white cow (homozygous dominant), what alleles will the offspring have?

A. Rw
B. RW
C. rW
D. rw



Answer :

Certainly! Let's examine the genetic cross between a red cow and a white cow, both of which are described as homozygous dominant.

1. Definition of Homozygous Dominant:
- A homozygous dominant organism has two copies of the dominant allele (e.g., "RR" or "WW"). In this case, we have:
- Red cow: RR (since it's homozygous dominant for the red color)
- White cow: WW (since it's homozygous dominant for the white color)

2. Crossing the Two Parents:
- To determine the alleles the offspring will have, we perform a genetic cross between RR and WW.

3. Formation of Alleles in Offspring:
- Each offspring will inherit one allele from each parent. Thus, each possible combination for the alleles must be considered.
- Since the red cow can only contribute an "R" allele and the white cow can only contribute a "W" allele, the offspring will consistently receive one "R" allele from the red cow and one "W" allele from the white cow.

4. Resulting Alleles of the Offspring:
- Therefore, the alleles of the offspring will be a combination of one allele from each parent, which results in "RW".

Hence, the alleles for the offspring of a red cow (homozygous dominant) crossed with a white cow (homozygous dominant) will be:
RW