Papillae are small structures present on the upper surface of tongue. Taste receptors are located around the papillae. There are four types of papillae i.e., fungiform, foliate, circumvallate and filiform. Fungiform papillae are mushroom shaped papillae present on the dorsal surface of tongue. Foliate papillae are less numerous and are leaf shaped. It is functional in herbivores and vestigial in humans. These are short vertical fold like structures present on each side and at the back of the tongue.
Circumvallate papillae are present on the backside of the tongue. Circumvallate papillae is the largest papillae. Filiform papillae have no taste buds and are keratinized. The well-developed filiform papillae are present in carnivores.