Chapter 6.5, Problem 27E

Genetics Traits passed from generation to generation are carried by genes. For a certain type of pea plant, the color of the flower produced by the plant (either red or white) is determined by a pair of genes. Each gene is of one of the types C (dominant gene) or c (recessive gene). Plants for which both genes are of type c (said to have genotype cc) produce white flowers. All other plants—-that is, plants of genotypes CC and Cc—-produce red flowers. When two plants are crossed, the offspring receives one gene from each parent.

Genotype	Color
Cc Cc CC	White Red Red

(a) Suppose that you cross two pea plants of genotype Cc. What is the probability that the offspring produces white flowers? Red flowers?

(b) Suppose that you have a batch of red-flowering pea plants, of which 60% have genotype Cc and 40% have genotype CC. If you select one of these plants at random and cross it with a white-flowering pea plant, what is the probability that the offspring will produce red flowers?