Definitions of as level biology enzymes key words
| Front | Lock and key theory |
| Back | The shape of the active site is very precise, and substrates that are not complementary to the shape of the active site cannot bind |
| Front | Active site |
| Back | Region in an enzyme which the substrate can bind to |
| Front | Immobilised enzymes |
| Back | Enzyme that have been fixed to a surface or within a bead of agar gel |