Question

the ability to taste phenylthiocarbamide (ptc) is a dominant trait. if a heterozygote woman has a child with a man who is not a taster, what is the chance will be a taster? multiple choice

Explanation:

Step1: Define alleles

Let \(T\) represent the dominant allele for tasting PTC and \(t\) represent the recessive allele for non - tasting. The heterozygous woman has the genotype \(Tt\) and the non - taster man has the genotype \(tt\).

Step2: Set up Punnett - square cross

When we cross \(Tt\times tt\), the possible gametes from the woman are \(T\) and \(t\), and the only possible gamete from the man is \(t\). The Punnett - square shows two possible genotypes for the offspring: \(Tt\) and \(tt\).

Step3: Calculate probability

Out of the two possible genotypes (\(Tt\) and \(tt\)), the genotype \(Tt\) results in a taster. So the probability of having a taster child (\(Tt\)) is \(\frac{1}{2}\) or 50%.

Answer:

50%