What causes bumps on the back of your tongue?

Lingual tonsils: Raised areas at the base of tongue (behind the curvature of tongue) are a normal variant of lymphatic tissue, like tonsils and adenoids. In fact they are called lingual tonsils and help form a protective ring of lymphatics in throat like immigration checkpoint against invading bacteria and viruses. They can cause snoring and sleep apnea. If recently enlarged then can be a sign of disease.