In the first step of their experiments, Jacob and Monod treated E. coli cells with UV light or X- rays in order to
A) decrease the number of viable cells.
B) increase the frequency of mutations in all genes.
C) selectively mutate the lac operon, leaving all other genes unmutated.
D) induce DNA repair enzymes.

Question

Quizplus · Accepted Answer

Jacob and Monod treated E. coli cells with UV light or X-rays in order to increase the frequency of mutations in all genes, not selectively mutate the lac operon or induce DNA repair enzymes. This was necessary in order to isolate mutants that were specifically affected in the regulation of the lac operon.

In the First Step of Their Experiments, Jacob and Monod