Question

Answer in detail.
What changes occur in food in the mouth?

Answer 1

The mouth is the first part of the digestive system. It receives food and starts mechanical digestion. The ingested food is first broken down in the mouth when it is chewed. Simultaneously it gets mixed with the saliva. This process is called mastication or mechanical digestion. It prepares the food for chemical digestion, that is, the digestion by action of enzyme. The teeth help in chewing down the food. There are 4 kinds of teeth. These are incisors, canines, premolars and molars, incisors are the cutting teeth. These help in biting and cutting the food. Canines are the tearing teeth that helps to tear and hold the food. Premolars and molars are the crushing and grinding teeth which help in grinding the food. When we chew the food it is mixed with saliva, secreted by salivary glands softens the food. Saliva contains an enzyme called salivary amylase also called ptyalin, acts on starch to convert it into maltose.

starch \[\ce{->[salivary][amylase]}\] maltose.