Final answer:
The large teeth in the rear of the mouth, the premolars and molars, are designed for chewing and grinding food, contributing to the mechanical digestion process.
Step-by-step explanation:
The large teeth in the rear of the mouth, which include the premolars and molars, serve the primary function of chewing and grinding food. These teeth are broad, flat, and equipped with several pointed cusps that efficiently crush food, preparing it for swallowing and further digestion. While the incisors at the front of the mouth are used for slicing off pieces of food and the canines (or cuspids) are used for tearing, it is the premolars and molars that handle the bulk of breaking down food through mechanical digestion.