Cellulases are enzymes that break down cellulose, a complex carbohydrate found in the cell walls of plants. These enzymes play a crucial role in the digestion of plant material, helping organisms like termites and fungi to access energy stored in plant fibers. In industrial applications, cellulases are used in processes such as biofuel production, where they help convert plant biomass into sugars that can be fermented into ethanol. They are also utilized in the textile and paper industries to improve the quality of products by enhancing fiber processing and reducing waste.