HUMAN NUTRITION

Detailed explanation-1: -Digestion begins immediately in the oral cavity with both mechanical and chemical digestion. Mechanical digestion in the oral cavity consists of grinding of food into smaller pieces by the teeth, a process called mastication.

Detailed explanation-2: -The primary function of the mouth is to introduce food into the digestive tract. Additional functions include communication and social interaction, grooming, protection, heat regulation (particularly in dogs), and grasping objects.

Detailed explanation-3: -The system starts at the mouth. The mouth connects via a tube, called the esophagus, to the stomach. The stomach is usually an acidic environment where food is broken down into smaller molecules. These molecules then travel to the small intestine where most of the nutrients are absorbed.