Final answer:
The region of an enzyme that catalyzes reactions is known as the active site. It is a specific part of the enzyme where the substrate binds, and this interaction is necessary for the enzyme to catalyze chemical reactions without being consumed itself.
Step-by-step explanation:
The region of an enzyme that catalyzes reactions is called the active site. Enzymes are proteins that speed up chemical reactions in the body by lowering the activation energy required. The active site is a unique and specific region on the enzyme where the substrate molecules bind, and it is typically a small portion of the enzyme's total structure, often described as a pocket or crevice. The shape of the active site and the substrate must be compatible, allowing the enzyme to bind to only specific substrate molecules, thus displaying specificity for their particular biochemical reaction.
Once the substrate is bound to the active site, the enzyme catalyzes the chemical reaction, transforming the substrate into products without being consumed in the process. This enables the enzyme to be used repeatedly for the same type of reaction. Enzymatic reactions have critical roles in the body and are fundamental for the functioning of biological systems.