The ability to taste the chemical PTC is determined by a single gene in humans with the ability to taste given by the dominant allele T and the inability to taste by the recessive allele t. Suppose two heterozygous tasters (Tt) have a large family.
QUESTION A: Predict the proportion of their children who will be tasters and non-tasters. Use a Punnett square to illustrate how you make these predictions.
QUESTION B: What is the likelihood that their first child will be a taster?
Tt x Tt= 1:TT 2:Tt 1: tt 75% of the offspring are PTC tasters (TT and Tt) 25% are not (tt). Every time they have a child, the odds are 75% taster, 25-% not.