AP BIOLOGY

Detailed explanation-1: -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 begins in your mouth with chewing, then moves to churning in the stomach and segmentation in the small intestine. Peristalsis is also part of mechanical digestion.

Detailed explanation-3: -The physical change occurs while chewing the food (big lump of food is broken into smaller pieces) and the chemical change is marked by the action of saliva on food. Since a chemical change occurs, digestion of food can be said to start in the mouth.

Detailed explanation-4: -Examples of physical digestion are grinding, chewing, biting, and tearing. Digestion begins as soon as we put food in our mouth. As we chew, we break down food into smaller pieces. Saliva then mixes with the food.

Detailed explanation-5: -Physical digestion (sometimes referred to as mechanical digestion) is the breakdown of food into smaller pieces without chemical change to the food molecules. The processes that take place during physical digestion help to increase the surface area of food for the action of enzymes during chemical digestion.