What begins the process of mechanical digestion?

The process of mechanical digestion begins in the mouth. In this stage, various actions such as chewing occur, which physically break down food into smaller pieces. The teeth play a crucial role in this process by grinding and tearing food, making it easier to mix with saliva and ultimately swallow. This mechanical breakdown is essential for effective digestion as it increases the surface area of the food, allowing digestive enzymes to act more efficiently later in the digestive process.

Saliva contributes to digestion by moistening food and contains enzymes that initiate chemical digestion, but it is the physical action of chewing in the mouth that starts the process of mechanical digestion. While the stomach also plays a role in mechanical digestion through churning and mixing the food, the initial phase is clearly established in the mouth.