Question

A woman that is homozygous recessive (bb) for blue eyes and a man that is heterozygous (Bb) for brown eyes have a child. Based on what you have learned about genotypes and phenotypes in regards to genetic alleles, answer the following questions:

1. What percentage of change is there that the child will have a phenotype of blue eyes? Explain.

2. If the child is born with blue eyes, would the pair of alleles the child carries be homozygous or heterozygous? Can blue eyes ever be heterozygous? Explain.

Answer 1

1. There is a 50% chance that the child will have blue eyes. It is rare for a homozygous recessive allele to be shown.

2. If the child has blue eyes the pair of alleles it carries would be homozygous. Blue eyes can never be heterozygous that is why it is a rare occurance that homozygous recessive alleles are shown. The is always a 50% chance that the alleles may be homozygous or hetrozygous.