TLS Online TPP Program

#Question id: 16130


You are studying regulation of the yeast enzyme glutamine synthetase (GS), which is encoded by the GLN1 gene. You have isolated two mutants, designated gln2– and gln3–, that give decreased GS activity. Mating of either gln2– or gln3– haploids to wild type produces heterozygous diploids that show normal amounts of GS expression. When you cross either a gln2– or gln3– haploid to a gln1– strain the resulting diploids show normal expression of GS.              
How many units of ß-galactiosidase would you expect to be expressed from deletion 1 in a gln2– mutant? 

#SCPH01 Biochemistry
  1. 1 units of beta-galactosidase expression in deletion 1 in a gln2 mutant
  2. 3 units of beta-galactosidase expression in deletion 1 in a gln2 mutant
  3. 0 units of beta-galactose expression in Deletion 1 in a gln2 mutant
  4. no change in beta-galactosidase expression in Deletion 1 in a gln2 mutant