Anatomy and Physiology of the Throat

The throat, which begins behind the nose and continues down the neck, has three main functions. According to the Children's Hospital of Philadelphia, it allows the passage of food and liquid into the digestive tract, it allows for the passage of air and breathing, and it functions to create sound and speech.

Anatomy

• The main structures of the throat are the pharynx, larynx and tonsils. The top of the throat, or pharynx, starts behind the nose, continues down past the mouth and ends at the esophagus, which leads to the stomach. The larynx and epiglottis are in front of the lower section of the pharynx. Air passes through the pharynx, past the epiglottis into the trachea and then down into the lungs. The tonsils are located in the oropharynx, which is the part of the throat directly behind the mouth.

Pharynx

• The pharynx is a tube of muscle that runs behind the nose and mouth and continues down the throat until it becomes the esophagus. The pharynx has three sections: the nasopharynx, which lies behind the nose; the oropharynx, which lies behind the mouth; and the laryngopharynx, behind the larynx. The pharynx functions by contracting the muscle to propel food down to the esophagus during swallowing. The pharynx remains open to allow breathing, and the bottom section prevents air from entering the esophagus and digestive tract when not swallowing.

Larynx

• The larynx, commonly known as the voice box, is the part of the throat that produces sound. The larynx has a skeleton made of cartilage, which surrounds the vocal cords. Vocal sound is made when air from the lungs causes a vibration in the vocal cords. The pitch of the sound is changed when the muscles in the larynx alter the tension in the vocal cords.

  The epiglottis is a flap of tissue on top of the vocal cords. It prevents food from entering the trachea and lungs.

Tonsils and Adenoids

• The tonsils and adenoids are the lymph tissue in the throat. The tonsils are located in the oropharynx and can be seen at the back of the mouth at the entrance to the throat. The adenoids are located in the nasopharynx, near the Eustachian tubes. The tonsils and adenoids help fight off infection. They are only a small part of the immune system, however, and can be removed if necessary.

Mouth, Ears and Nose

• The throat is connected to the mouth, ears and nose. The mouth is connected to the pharynx and is used to take in food and liquid, as well as to articulate the voice. The ear is connected to the throat by the Eustachian tube. It is a common place for infection, especially in children. The back of the nose is connected to the nasopharynx.