What is saliva and how does it help with digestion?

Answer 1

Saliva is a clear, watery fluid produced by the salivary glands located in the mouth. It plays a crucial role in the process of digestion

Moistening and Lubricating: Saliva keeps the mouth moist, which aids in chewing, swallowing, and speaking. It lubricates the food, making it easier to form a bolus (a soft mass) that can be swallowed and transported through the esophagus.

Enzymatic Action: Saliva contains enzymes, such as amylase and lingual lipase, which initiate the breakdown of starches and fats, respectively. Amylase starts the digestion of carbohydrates by breaking down complex starches into simpler sugars like maltose. Lingual lipase begins the digestion of fats, particularly triglycerides, into fatty acids and diglycerides.

Taste and Sensation: Saliva contains taste buds and other sensory receptors that help in the perception of taste. It carries dissolved food particles to the taste buds on the tongue, allowing us to experience flavors and enjoy our food.

pH Regulation: Saliva helps maintain the pH balance in the mouth. It contains bicarbonate ions, which help neutralize acids produced by oral bacteria and acidic foods. This buffering action helps prevent tooth decay and maintains a healthy oral environment.

Antibacterial Properties: Saliva contains antimicrobial agents, including lysozyme and immunoglobulins, which help control the growth of bacteria and other microorganisms in the mouth. These properties contribute to oral hygiene and the prevention of oral infections.

Answer 2

Saliva is a fluid produced and secreted by the salivary glands. It is composed of water, mucous, and enzymes. Saliva helps digestion by moistening the food (a physical change), and breaking down starches in the foods with its enzymes (a chemical change).