Assume that the structural genes of the lac operon have been fused, through recombinant DNA techniques, to the regulatory apparatus of the ara operon. If arabinose is provided in a minimal medium to E. coli carrying this gene fusion, would you expect β-galactosidase to be produced at induced levels? Why?

The correct answer is "Yes, β-galactosidase would be produced at induced levels".

Explanation:

The L-arabinose operon, also known as ara operon, is activated in the absence of glucose and in the presence of arabinose. In this study the ara operon was fused with the lac operon, therefore arabinose would active not only the genes of ara operon but also lac operon. Once the researchers provide E. coli with arabinose, the bacteria would produce β-galactosidase as a result of lac operon activation.