Final answer:
The lock-and-key analogy is inadequate because it does not account for the enzyme's active site's dynamic structural changes upon substrate binding, as described by the induced-fit model.
Step-by-step explanation:
The analogy of enzyme-substrate binding being compared to a lock and key is flawed because it oversimplifies the dynamic nature of enzyme action. The lock-and-key model suggests that the enzyme's active site and substrate have fixed, complementary shapes that fit together without altering their structure. However, the induced-fit model provides a more accurate description by proposing that the enzyme's active site undergoes a mild structural change upon substrate binding. This conformational change helps form a snug fit around the substrate, enhancing the enzyme's ability to catalyze the reaction.