Final answer:
The oral cavity refers to the mouth, which is involved in the initiation of digestion, while the teeth are used for chewing food, and the tongue assists in food manipulation and swallowing.
Step-by-step explanation:
The oral cavity, also known as the mouth or buccal cavity, is the point of entry for food into the digestive system. It is framed by the cheeks, tongue, and palate. The oral cavity, specifically the oral vestibule, is bounded externally by the cheeks and lips, and internally by the gums and teeth. Within this cavity, the process of digestion begins with mastication, which is the chewing action performed by the teeth. The tongue plays a crucial role in manipulating food for chewing and is involved in the act of swallowing.
Addressing the question: The oral cavity is classified as the part of the mouth as well as the point of entry of food into the digestive system. The teeth are classified as structures used for mastication, aiding in the physical breakdown of food, and the tongue is classified as a muscular organ important for taste, food manipulation, and swallowing.