TLS Online TPP Program

#Question id: 15147


You have isolated a set of five yeast mutants that form dark red colonies instead of the usual white colonies of wild-type yeast. You cross each of the mutants to a wild-type haploid strain and obtain the results shown below;
you cross each haploid mutant strain to a different haploid mutant of the opposite mating type. From the results shown below deduce as much as you can about which mutations lie in the same gene. Clearly state any remaining ambiguities and suggest some general ways that the ambiguities might be resolved
a) That mutants 1 and 3 form one complementation group and are mutations in the same gene (gene A) 
b) That mutations 2 and 5 form a second complementation group and are mutations in a second gene (gene B).
c) That mutations 3 and 5 form a second complementation group and are mutations in a second gene (gene B).
d) The first ambiguity is whether mutant 4 has a mutation in gene A or B, or whether it represents a unique gene.
Which of the following is the correct prediction about mutants?

#Unit 8. Inheritance Biology
  1. b, c and d
  2. a, b and c
  3. c and d only
  4. a, b and d