Chapter 11.7, Problem 43PE

Scientist Gregor Mendel (1822-1884) is often called the “father of modem genetics� and is famous for his work involving the inheritance of certain traits in pea plants. Suppose that the genes controlling the color of peas are $\text{Y}$ for yellow and $\text{y}$ for green. Each plant has two genes, one from the female (seed) and one from the male (pollen). The $\text{Y}$ gene is dominant, and therefore a plant with genes $\text{YY}$ will have yellow peas, a plant with genes $\text{Yy}$ or $\text{yY}$ will have yellow peas, and a plant with genes $\text{yy}$ will have green peas.

If a plant with two yellow genes $\left(\text{YY}\right)$ is crossed with a plant with two green genes $\left(\text{yy}\right)$ , the result is four hybrid offspring with genotypes $\text{Yy}$ . The offspring will be yellow, but will carry the recessive green gene.

Suppose that both parent pea plants are hybrids with genotype $\text{Yy}$ .

a. Make a chart showing the possible genotypes of the offspring.

b. What is the probability that a given offspring will have green peas?

c. What is the probability that a given offspring will have yellow peas?