The Punnett square below shows the genotypes of two parents for trait R. Trait R is the Mendelian trait in humans for tongue rolling. The allele for the ability to roll the tongue (R) is dominant over the allele for the inability to roll the tongue (r). Use this Punnett square to answer to following three questions.
Mom
R r
R
Dad
r RR Rr
Rr rr
1. What is the mother’s genotype and phenotype?
2. What is the father’s genotype and phenotype?
3. What is the probability that their child will be able to roll their tongue?
4. Use the following information to answer questions #9-#13.
Consider two traits in humans: freckles (F) and widow’s peak (W). Having freckles (F) is dominant over not having freckles (f), and having a widow’s peak (W) is dominant over not having a widow’s peak (w).
Suzy is heterozygous for freckles and widow’s peak.
José is homozygous recessive for freckles and widow’s peak.
Suzy and José are about to have a baby, and they are curious about the likelihood that their child will inherit these traits.
5. What is the likelihood that Suzy and José’s child will have freckles but will not have a widow’s peak?
6. What is the likelihood that Suzy and José’s child will not have freckles but will have a widow’s peak?
7. What is the likelihood that Suzy and José’s child will have freckles and a widow’s peak?
8. What is the likelihood that Suzy and José’s child will not have freckles or a widow’s peak?
