Question

A man having a dominant genetic trait (TT genotype) can laste phenylthiocarbamide (PTC), marries a woman who cannot taste PTC. The PTC tasting ability of their biological son and daughter is

• A. Son taster; Daughter non-taster
• B. Daughter taster, Son non-taster
• C. Both are non-tasters
• D. Both are tasters

Answer 1

The Correct Option is D

This question revolves around understanding genetics, particularly the inheritance of the ability to taste phenylthiocarbamide (PTC). PTC tasting is a classic example of simple Mendelian inheritance where the ability to taste PTC is determined by a dominant allele.

Let's break down the problem:

1. Genotype Explanation: In this scenario, we have two possible genotypes:
   • TT or Tt: Taster (can taste PTC).
   • tt: Non-taster (cannot taste PTC).
2. Parent Genotypes:
   • The man has a genotype TT which means he is a taster and homozygous for the taster allele.
   • The woman is a non-taster with the genotype tt.
3. Offspring Genotypes:
   • The offspring receive one allele from each parent.
   • Therefore, the children will have genotypes:
     • T (from the father) + t (from the mother) = Tt
   • Since Tt includes the dominant allele T, both offspring will be tasters.
4. Conclusion: Both the son and the daughter will have the genotype Tt and, therefore, both will be tasters. Thus, the correct option is:
   Both are tasters
   .