What type of proteins act as catalysts in biochemical reactions?

Enzymes are specialized proteins that function as catalysts in biochemical reactions, meaning they accelerate the rate of these reactions without being consumed or permanently altered in the process. They achieve this by lowering the activation energy needed for chemical reactions to occur, which increases the likelihood that substrates will interact and form products.

Each enzyme is specific to a particular reaction or type of reaction, often determined by its unique three-dimensional structure. This specificity allows enzymes to play crucial roles in a wide variety of biological processes, including digestion, metabolism, and DNA replication.

In contrast, antibodies are proteins involved in the immune response, hormones are signaling molecules that regulate physiological processes, and structural proteins provide support and shape to cells and tissues. While important for their respective functions, they do not catalyze biochemical reactions like enzymes do. This distinction highlights why enzymes are key to understanding metabolic pathways and biochemical processes within organisms.