Answer to Question #308240 in Genetics for Mark

Question

1. Most individuals of a certain wild flower have white petals, but a few are blue. Crosses have shown that the blue color is due to a recessive allele. Use "W" for white and "w" for blue.

a. What is the genotype of a blue-flowered plant and what gametes would it produce as a result of meiosis?

b. What is/are the genotype(s) of each of a blue-flowered plant's parents?

c. If a blue-flowered plant has two white-flowered parents, and the parents produced many offspring, what fraction of them would you expect to be blue?

d. If a blue-flowered plant is crossed with its white-flowered parent, what fraction of their offspring would have the genotype "ww"?

e. If two blue-flowered plants cross, what fraction of their offspring will be blue? White?

Answer 1

(a) Genotype of blue-flowered plant is homozygous ww, and the all the gametes will be (w)

(b) The genotypes of the blue-flowered plants parents are either Ww or ww

(c) 1/4 of them will be blue

(d) The cross will be Ww x ww

The offspring that will be blue will be genotype ww will be 1/2 (half)

(e) All offspring will be blue, and none will be white