When a blue-eyed male mates with a heterozygous brown-eyed female, what is the expected ratio of brown-eyed to blue-eyed children?

• A. 2:1
• B. 1:1
• C. 3:1
• D. 1:2

Answer: (B)

In this scenario, we are analyzing the genetic inheritance of eye color. The trait for brown eyes (represented by the dominant allele "B") and the trait for blue eyes (represented by the recessive allele "b") follows Mendelian inheritance patterns.

The blue-eyed male has the genotype "bb," meaning he has two recessive alleles. The heterozygous brown-eyed female possesses the genotype "Bb," where she has one dominant allele for brown eyes and one recessive allele for blue eyes.

When these two individuals mate, we can set up a Punnett square to visualize the potential genetic combinations of their offspring. The possible gametes from the male (bb) will always contribute a "b" allele. The female (Bb), however, can contribute either a "B" allele or a "b" allele.

The resulting combinations from the Punnett square would be:

• From the male: b (always)

• From the female: B (with 50% probability) or b (with 50% probability)

The possible genotypes of their offspring are:

1. Bb (brown-eyed)

2. bb (blue-eyed)

This results in one brown-eyed child (Bb) for every blue-eyed child (bb),