ANATOMY

Detailed explanation-1: -Mechanical digestion in the oral cavity consists of grinding of food into smaller pieces by the teeth, a process called mastication. Chemical digestion in the mouth is minor but consists of salivary amylase (ptyalin, or alpha-amylase) and lingual lipase, both contained in the saliva.

Detailed explanation-2: -Both mechanical and chemical digestion occur in the mouth. Teeth grind and break up food (mechanical), while an enzyme in saliva called amylase begins to break down carbohydrates (chemical). After it is swallowed, the chewed food (now called a bolus) moves down the esophagus.

Detailed explanation-3: -The large pieces of food that are ingested have to be broken into smaller particles that can be acted upon by various enzymes. This is mechanical digestion, which begins in the mouth with chewing or mastication and continues with churning and mixing actions in the stomach.