So let's follow the pathway of the food as we place it inside our mouth. Now the mouth portion is basically known as the oral cavity. This is where we place our food. Now as we chew our food we're basically mechanically digesting that food. Mechanical digestion refers to the process by which we break down large food particles into smaller food particles. And what this does is this increases the surface area on which the enzymes, the proteolytic digestive enzymes can actually act on.