Question

Give the function of saliva in digestion.

Answer 1

With the aid of saliva, the teeth and tongue mix and chew the food thoroughly. Saliva helps to moisten food and help to produce the food bolus so that it can be swallowed quickly.

Complete answer:
The process of digestion begins with the mouth and the intake of food. The teeth have a major role to play in chewing or actively breaking down food into tiny fragments. The food is thoroughly mixed with saliva and moved across the mouth when chewing via the muscular tongue. The food is chemically broken down by enzymes present in saliva. The saliva in the oral cavity includes electrolytes and enzymes, salivary amylase and lysozyme. The hydrolytic action of the digestion enzyme, salivary amylase, in the oral cavity initiates the chemical process of digestion. Lysozyme found in saliva helps prevent infection by killing harmful bacteria.

The oesophagus is a long tube connecting the mouth to the stomach. The muscles of the oesophagus force the food to the stomach with the help of smooth muscle contractions. Gastric juices, like stomach enzymes, act on the particles of the food and facilitate digestion. Further digestion of food begins in the small intestine, where enzymes generated by the liver, the small intestine, and the pancreas facilitate the process of digestion. The process of digestion thus begins in the mouth with the help of saliva.

Note: Digestion involves the mechanical and chemical breakdown of food into small substances, facilitating the absorption and assimilation of nutrients by the body.