In enzyme activity, what is a substrate?

A substrate is the specific molecule that an enzyme acts upon during a biochemical reaction. Enzymes are catalysts that speed up chemical reactions by binding to their substrates at an active site. This interaction forms an enzyme-substrate complex that facilitates the transformation of the substrate into products, ultimately leading to a chemical reaction.

Understanding the role of a substrate is crucial, as it underlines the specificity of enzymes; each enzyme is designed to work with particular substrates based on their structure and chemical properties. This specificity is a fundamental concept in biochemistry, as it explains how enzymes can regulate and catalyze various metabolic pathways in living organisms.