Anterior two third of the tongue is demarcated from the posterior one third by: plexus, 2-long thoracic plexus, 2-long thoracic
Passavant's ridge
Sulcus terminalis
Circurnvallatepapillae
Filifonn papilla
Ans: B. Sulcus terminalis(Ref Gray's 41/e p5 I I, 40/e p503)Anterior two third of the tongue is demarcated from the posterior one-third by sulcus terminalis.Tongue:Divided by a V-shaped sulcus terminalis.Fuher divides tongue into,Anterior, oral (presulcal) pa facing upwards.Posterior, pharyngeal (postsulcal) pa facing posteriorly.Anterior pa forms about two-thirds of tongue length.