Final answer:
The induced-fit model of enzyme action explains how enzymes and substrates undergo dynamic modifications during the reaction.
Step-by-step explanation:
The induced-fit model of enzyme action accounts for the flexibility of enzyme and substrate molecules. According to this model, the flexibility of the enzyme molecule allows the active site to adapt to the shape of the substrate and, at the same time, the substrate adopts the shape of the enzyme to acquire the best possible orientation for the reaction to occur. The active site shape re-adjusts to let the products be released, allowing the next cycle of the enzyme action. The observation from experiments during the actual catalysis reaction supports the view that not only does the active site of the enzyme change shape, but the backbone and the side chains of the enzyme molecule remain in constant motion during the enzyme action.