Oxidoreductases are a class of enzymes that facilitate oxidation-reduction reactions in biological systems. These reactions involve the transfer of electrons between molecules, which is essential for various metabolic processes. Oxidoreductases play a crucial role in cellular respiration, photosynthesis, and the metabolism of nutrients. These enzymes are categorized based on the type of electron donor and acceptor involved in the reaction. Common examples include dehydrogenases, which remove hydrogen from substrates, and oxidases, which transfer electrons to oxygen. By regulating these reactions, oxidoreductases help maintain cellular energy balance and overall metabolic health.