Chapter 5, Problem 47P

A single yeast cell placed on a solid agar will divide mitotically to produce a colony of about 10 cells. A haploid yeast cell that has a mutation in the ade2 gene will produce a red colony; an ade2⁺ colony will be white. Some of the colonies formed from diploid yeast cells with a genotype of ade2⁺ / ade2− will contain sectors of red within a white colony.

a.	How would you explain these sectors?
b.	Although the white colonies are roughly the same size, the red sectors within
	some of the white colonies vary markedly in size. Why? Do you expect the
	majority of the red sectors to be relatively large or relatively small?