Describe the mechanism(s) as to which an enzyme binds to a substrate.

Two models have been proposed. The first being the 'Lock and Key Model' which simply describes the way in which the active site of an enzyme is complementary to the substrate shape, meaning that only the correct substrate for that enzyme can bind and fit into the active site causing a reaction. But a more developed model is the 'Induced Fit Model' which is similar to the 'Lock and Key' in that the substrate and active site shapes complement eachother, but this time, when the enzyme substrate complex forms, the active site undergoes a conformational changing, making the binding to the substrate stronger and more specific.