Enzymes, which are proteins, act as biological catalysts. They accelerate chemical reactions by reducing the activation energy necessary for the reaction to occur. Each enzyme exhibits high specificity for its substrate (the molecule it interacts with), a characteristic dictated by the enzyme's distinct active site. Enzymes are regenerated after catalyzing reactions and can be reused. Furthermore, enzymes function optimally within a specific temperature and pH range. Therefore, the assertion that enzymes are substrate-specific is accurate.