If a strain of bacteria had a mutation that blocked expression of the lac repressor, what would you expect as a result?
A. The mutant strain would outcompete wildype strains, since it could always utilize lactose.
B. The mutant strain would act the same, because it would still require lac activator protein to turn on.
C. The mutant strain would waste energy producing enzymes in the absence of lactose.
D. The mutant strain would grow at the same rate as wildtype if lactose was not present.
Answer: C
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