Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 5, Problem 42P
Indicate the percentage of tetrads that would have 0, 1, 2, 3, or 4 viable spores after Saccharomyces cerevisiae a / α diploids of the following genotypes are sporulated:
a. | A true-breeding wild-type strain (with no mutations in any gene essential for viability). |
b. | A strain heterozygous for a null (completely inactivating) mutation in a single essential gene. |
For the remaining parts of this problem, consider crosses between yeast strains of the form
|
|
c. | a and b are unlinked, and both are 0 m.u. from the centromere. |
d. | a and b are unlinked; a is 0 m.u. from the centromere, while b is 10 m.u. from the centromere. |
e. | a and b are 0 m.u. apart. |
f. | a and b are 10 m.u. apart. Assume all crossovers between a and b are SCOs (single crossovers). |
g. | In part (f), if a four-strand DCO (double crossover) occurred between a and b, how many of the spores in the resulting tetrad would be viable at high temperature? |
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Chapter 5 Solutions
Genetics: From Genes to Genomes
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