Enzymes are considered to be proteins. They function as biological catalysts that accelerate chemical reactions within organisms by lowering the activation energy required for these reactions to occur. Each enzyme is specific to a particular substrate, binding to it at an active site and facilitating its conversion into products. This specificity is crucial for regulating metabolic pathways and maintaining homeostasis in living cells. Enzymes play vital roles in various processes, including digestion, DNA replication, and energy production.