Enzymes showing substrate specificity are specific to, how many substrates?

Explanation

In an enzyme activity, the substrate must bind with the enzyme to become a catalyst of a chemical reaction. And most enzymes are highly specific, particularly to the nature of the substrate they bind to. Substrate specificity is one of the most essential distinctive features of enzymes. As the term indicates, an enzyme can only be specific to one substrate. This process is further explained by Emil Fischer's 'Lock and Key' model. It explains that an enzyme is specific to a single substrate. In the same way only a single key can open a lock, only a specific substrate can act on an enzyme. In an enzyme activity, the substrate must bind with the enzyme to become a catalyst of a chemical reaction. And most enzymes are highly specific, particularly to the nature of the substrate they bind to.