Which enzyme is the first to be added during digestion in the mouth?

Amylase is the first enzyme introduced during digestion in the mouth, making it vital for the initial breakdown of carbohydrates. Specifically, salivary amylase (also known as ptyalin) is secreted by the salivary glands and begins the process of starch digestion while food is still in the mouth. It hydrolyzes starch into maltose and dextrins, facilitating easier digestion as the food moves through the digestive system.

In contrast, proteases are enzymes that break down proteins and are primarily active in the stomach, where conditions are more suitable for protein digestion. Pepsin is actually the main protease active in the stomach, not the mouth, and is secreted in an inactive form called pepsinogen. Lipase, while important for lipid digestion, is also not the primary enzyme active in the mouth; it functions later in the digestive process, primarily in the stomach and small intestine, for the breakdown of fats.

This focus on amylase emphasizes the starting point of carbohydrate digestion in the mouth, highlighting the specialized function of enzymes in different sections of the digestive system.