Which components are found in saliva?

The presence of salivary amylase, water, and mucous in saliva is essential for several functions during the initial stages of digestion. Salivary amylase is an enzyme that catalyzes the breakdown of starches into sugars, initiating the digestive process even before food reaches the stomach. The water component is crucial as it helps dissolve food particles, making it easier for enzymes to act on the food. Additionally, mucous acts as a lubricant, aiding in the smooth passage of food through the oral cavity and into the esophagus.

In contrast, digestive enzymes and bile are not components of saliva; bile is produced by the liver and aids in fat digestion in the small intestine. Peptidase is also not a part of saliva; it is an enzyme that functions in the stomach and small intestine to break down proteins. Gastric juices, produced in the stomach, contain various enzymes and acids but are not found in saliva, which is specifically produced by the salivary glands. Therefore, the inclusion of salivary amylase, water, and mucous accurately reflects the composition and functional role of saliva in the digestive system.