The way you taste certain flavors is a genetic trait inherited from your parents. For instance, the ability to taste the bitter compound phenylthiocarbamide (PTC) is inherited as a dominant trait in humans. In the United States, approximately 70% of the population can taste PTC, whereas 30% cannot.

Every person inherits a pair of genes from their parents. Let T represent the gene for tasters (dominant), and let t represent the gene for nontasters (recessive). The presence of at least one T means that a person can taste PTC.
a. Complete the rectangle diagram of possible gene-pair combinations. Using the variables T and t, what algebraic expression does this diagram represent?
b. The sum of all possible gene-pair combinations must equal 1, or 100%, for the entire population. Write an equation to express this relationship.
c. Use the fact that 70% of the U.S. population are tasters to write an equation that you can use to solve for t.
d. Solve for t, the frequency of the recessive gene in the population.
e. What is the frequency of the dominant gene in the population?
f. What percentage of the U.S. population has the gene-pair TT?

Transcribed Image Text:

T2 그