Final answer:
Lactose would accumulate if lactase is inhibited, as it would not be broken down. This situation pertains to lactase enzyme activity, possibly relating to the lac operon system in bacteria, where lactose is necessary to remove the repressor and allow digestion of lactose.
Step-by-step explanation:
If lactase dehydrogenase is inhibited, lactose would accumulate because it would not be broken down efficiently. The question, however, appears to contain a small error, as lactase is the enzyme that breaks down lactose, whereas lactate dehydrogenase is involved in the metabolism of pyruvate to lactate during anaerobic respiration.
When lactose intake exceeds the lactase available to digest it, undigested lactose remains in the digestive system. Within the context of bacteria and the lac operon, when lactose is available, it binds to the repressor and removes it from the operator.
This allows RNA polymerase to transcribe the genes necessary to digest lactose. If lactase, responsible for breaking down lactose, was not present or was inhibited, it would prevent lactose from being metabolized, which would lead to an accumulation of lactose within the bacterial cell.