Substrates bind to what site on an enzyme?

The active site of an enzyme is the specific region where substrates bind. This site is uniquely shaped and chemically suited to accommodate the substrate(s), enabling the enzyme to facilitate a biochemical reaction. The lock-and-key model and the induced fit model describe how the active site interacts with its specific substrates, ensuring high specificity and catalytic efficiency.

In contrast, the allosteric site is a different area on the enzyme that binds regulatory molecules, which can alter the enzyme's activity either by enhancing or inhibiting its function, but is not directly involved in substrate binding. The competitive site is not a formal term commonly used in enzyme biology; competition refers more to the dynamics of substrate and inhibitor interactions at the active site. Lastly, an inhibitory site would generally refer to areas where inhibitors might bind, but this still would not be the point of substrate binding, thus distinguishing it from the active site function.