Distribution of various types of papillae on the human tongue

The sulcus terminans is located posterior to the vallate papillae and serves to separate the tongue from the lingual root. The root of the tongue, the "lingual tonsil," is free of papilla and instead has mucous glands and lymphatic tissue. From the vallate papillae to the tip of the tongue, the tongue is covered in filiform and fungiform papillae. (Derived from an image prepared for the National Cancer Institute - SEER Training Modules, a US government training program. Public domain. Edited and relabeled by Dr. Douglas J Lanska.)