What is the role of oral cavity in the digestion of food in the human beings

The oral cavity is the opening through which food is taken into the mouth and its contents. It is the first part of the alimentary canal. It is bounded by teeth in the front and upper and lower palate. It consists of teeth, tongue, jaws and receives the secretion of salivary glands.
Saliva in the oral cavity contains an enzyme (amylase) for digestion of starch. 

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