Part A: If the ability to taste PTC were controlled by only two alleles: one dom
ID: 278782 • Letter: P
Question
Part A: If the ability to taste PTC were controlled by only two alleles: one dominant (T) and one recessive (t), would there be any way to distinguish between the heterozygous (Tt) individuals and homozygous dominant (TT) individuals without mating or performing DNA analysis? Explain your answer.
Part B: Explain how a child could display a dominant phenotype that was inherited from two recessive phenotype parents.
Part C: Explain the purpose of using two different taste papers to test for the ability to taste PTC.
Explanation / Answer
Ans a) If you are a taster, one could be either TT or tt where one of the T is from either mother or father that predicts one of the parent is definitely a taster. If you are a taster it is sure that atleast one of your parents is definitely a taster (TT or Tt) as the dominant trait T is passed on to you. If you are a non-taster it is still possible that one of your parents is taster as they could be heterozygous (Tt) and you received the recessive gene.
Ans b) There is a possibility that a child could display dominant phenotype that was inherited from two recessive phenotype parents in case both the parents were heterozygous. By inheriting the dominant allele from both recessive parents, the child can be dominant.
Ans c) PTC tasting is a simple genetic trait which is governed by pair of alleles either dominant T for tasting and recessive for non-tasting. Using two different taste papers to test for the ability to taste PTC is to find out if the person is dominant or recessive for tasting.