Final answer:
Saliva's primary functions include moistening food, forming it into a bolus, and beginning the digestion of starches and fats. It also maintains oral hygiene and assists in taste perception.
Step-by-step explanation:
Saliva moistens ingested food and helps it become a slick, semisolid bolus that is more easily swallowed. Saliva also moistens, cleanses, and lubricates the oral cavity structures.
The key roles of saliva include moistening and dissolving food, which allows you to taste it. It also cleans and lubricates the teeth and oral cavity. The presence of enzymes like salivary amylase facilitates the breakdown of starch into maltose, while the enzyme lingual lipase begins the breakdown of fats. These digestive enzymes, along with mucus in the saliva, help in forming the bolus, preparing the food for swallowing. Moreover, saliva contains bicarbonate and phosphate ions that maintain the pH balance, as well as immunoglobulins (such as Immunoglobulin A) and lysozymes, providing antibacterial action that helps maintain oral and dental health.