Twenty-Five Years Ago,when Oshima and Colleagues Discovered That a Mutation

Multiple Choice

Twenty-five years ago,when Oshima and colleagues discovered that a mutation in the GAL4 gene led to the inability to synthesize all five enzymes required for galactose catabolism (breakdown) ,they couldn't be blamed for wanting to apply a bacterial model to explain this finding.What they expected,but did not find,was _____.

A) for all five genes to constitute an operon
B) five widely separated genes,each containing a GAL4 binding site in its regulatory region
C) for chromatin decondensation to play an important role in regulating the genes of galactose catabolism
D) for transcription to be important in regulating the genes of galactose catabolism