NEET BIOLOGY

Detailed explanation-1: -Digestion begins immediately in the oral cavity with both mechanical and chemical digestion. Mechanical digestion in the oral cavity consists of grinding of food into smaller pieces by the teeth, a process called mastication.

Detailed explanation-2: -Mechanical Digestion 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.

Detailed explanation-3: -Mechanical breakdown starts with mastication (chewing) in the mouth. Teeth crush and grind large food particles, while saliva provides lubrication and enables food movement downward. The slippery mass of partially broken-down food is called a bolus, which moves down the digestive tract as you swallow.

Detailed explanation-4: -A digestive enzyme in saliva called amylase (pronounced: AH-meh-lace) starts to break down some of the carbohydrates (starches and sugars) in the food even before it leaves the mouth.

Detailed explanation-5: -The mechanical breakdown of food occurs via muscular contractions called peristalsis and segmentation. Enzymes secreted by the salivary glands, stomach, pancreas, and small intestine accomplishes the chemical breakdown of food.