Question

In humans, brown eyes (B) are dominant, and blue eyes are recessive (b). If a homozygous dominant male is crossed with a heterozygous female, what are the most likely genotypes of the offspring?

Answer 1

When a homozygous dominant male with brown eyes is crossed with a heterozygous female, 50% of the offspring will be homozygous dominant and 50% will be heterozygous, resulting in all brown-eyed children.

Step-by-step explanation:

In humans, brown eyes (B) are dominant, and blue eyes (b) are recessive. When a homozygous dominant male (with genotype BB) is crossed with a heterozygous female (with genotype Bb), the offspring will most likely have the following genotypes:

• 50% are likely to be homozygous dominant (BB)
• 50% are likely to be heterozygous (Bb)

Since brown eyes are dominant, all of the offspring will have brown eyes. The presence of the dominant allele B ensures that even the heterozygous offspring express the brown-eyed phenotype.

Answer 2

B B

B BB BB

b Bb Bb

If you create a punnet square with the parents, you can see all possible outcomes for the offspring. The offspring will be 50% homozygous dominant with brown eyes and 50% heterozygous also with brown eyes.