Tonsils and adenoids are masses of tissue that are similar to the lymph nodes or “glands” found in the neck, groin, and armpits. Tonsils are the two masses in the back sides of the throat. The adenoid, also called the pharyngeal tonsil, is really a single midline structure high in the throat behind the nose and the roof of the mouth. It is not visible through the mouth without special instruments.
Tonsils and adenoids are near the entrance to the breathing passages, where they can easily catch incoming germs that can cause infections. Although tonsils and adenoids may be important in the first few weeks of life, after that they just seem to get in the way. Children who have their tonsils and adenoids removed suffer no ill effects or loss in their resistance to infection.