Wendy’s mother has blue eyes and her father has brown eyes. The allele for brown eye color is dominant (B) ?to the allele for blue eye color (b), ?but Wendy has blue eyes. Therefore, Wendy’s ________ ?must be ________ ?and her father’s must be Bb.
The correct answer and explanation is:
Answer:
Wendy’s genotype must be bb, and her father’s must be Bb.
Explanation:
Eye color in humans is primarily determined by genetic inheritance, with brown eyes being a dominant trait and blue eyes being a recessive trait. This means that for a person to have blue eyes, they must inherit two copies of the recessive allele (b), one from each parent.
Understanding Dominance and Recessiveness
- The brown eye allele (B) is dominant, meaning that if a person has at least one B allele, they will have brown eyes.
- The blue eye allele (b) is recessive, meaning that a person will only have blue eyes if they inherit two b alleles (bb), one from each parent.
Wendy’s Genotype
Since Wendy has blue eyes, she must have inherited two recessive b alleles, one from her mother and one from her father. This means her genotype must be bb.
Her Father’s Genotype
Wendy’s mother has blue eyes, meaning her genotype must be bb, as she can only pass the b allele to her children.
Wendy’s father has brown eyes, which means he could have either of the following genotypes:
- BB (homozygous dominant)
- Bb (heterozygous, meaning he carries both a dominant and a recessive allele)
However, since Wendy has blue eyes (bb), she must have inherited a b allele from her father. This means her father cannot be BB because then he would only have B alleles to pass on. Instead, he must be Bb, meaning he carries one dominant allele (B) and one recessive allele (b).
Conclusion
For Wendy to have blue eyes, she must be bb. Since her mother is bb and her father has brown eyes but passed a b allele, he must be Bb. This confirms that Wendy’s genotype is bb, and her father’s genotype is Bb.