The Obvious Advantage of the Lac Operon is That It

Question

The obvious advantage of the lac operon is that it ________________________.  
A) allows bacteria to survive in the presence of lactose
B) eliminates the need for lactose-metabolizing enzymes when lactose is not present
C) enables bacteria to make lactose only in the presence of the proper enzymes
D) negates the need for milk in the diet of adult humans
E) enables glucose to substitute for lactose in the diet of lactose intolerant persons

Accepted Answer

The lac operon allows bacteria to save energy and resources by only producing the enzymes necessary to metabolize lactose when lactose is present in the environment. This means that the bacteria do not waste energy producing lactose-metabolizing enzymes when they are not needed.