Mouth

The mouth is the opening in the head that marks the beginning of the food passage. It is where food and drink are taken in, chewed, and mixed with saliva before being swallowed. In humans and many other animals, the mouth is also one of the organs the body uses to produce sound and speech.

The mouth consists of the lips, inner cheeks, teeth, tongue, hard palate, and soft palate. The interior is lined with a moist mucous membrane. Salivary glands empty into the mouth, beginning the breakdown of carbohydrates through enzyme action on food.

Anatomy

The lips form the outer boundary, with circular muscles controlling their movement. The teeth are set in the two arches of the mouth: upper and lower. The tongue is a muscular organ that moves food around and bears taste receptors (papillae) on its surface. Toward the rear, the mouth connects to the pharynx.

Functions

The primary function is to take in and chew food, breaking it into small pieces to facilitate swallowing and digestion. Saliva contains enzymes that aid in breaking down carbohydrates. The mouth also serves as an alternative airway when the nose is blocked and plays a role in sound production: air from the lungs is shaped by the tongue, lips, and teeth to create speech sounds.

Oral health

The mouth harbors many bacteria. Poor hygiene and high sugar consumption lead to tooth decay and gum disease. Tobacco and alcohol use are linked to increased risk of oral cancer. Standard preventive measures include regular brushing, fluoride use, and dental examinations.