What enzyme is responsible for breaking down starch in the human body?

Amylase is the enzyme responsible for breaking down starch in the human body. It plays a crucial role in the digestion of carbohydrates. This enzyme catalyzes the hydrolysis of starch, which is a polysaccharide made up of many glucose units. The breakdown begins in the mouth, where salivary amylase is secreted by the salivary glands, and continues in the small intestine, where pancreatic amylase further breaks down the starch into maltose and other disaccharides.

This process is essential as it transforms complex carbohydrates into simpler sugars, which the body can absorb and utilize for energy. Without amylase, the digestion of starch would be inefficient, affecting glucose availability for cellular processes. The other enzymes listed, such as lactase and protease, are specialized for breaking down lactose (the sugar in milk) and proteins, respectively, while cellulase, although involved in the breakdown of cellulose in other organisms, is not present in significant amounts in the human digestive system and thus does not contribute to starch digestion.