Taste bud

Taste buds (or lingual papillae) are small structures on the upper surface of the tongue that provide information about the taste of food being eaten.

The human tongue has about 10,000 taste buds. There are four types of taste buds present in the human tongue.

• Fungiform papillae – as the name suggests, these taste buds are slightly mushroom shaped if looked at in section. These are present mostly at the apex (tip) of the tongue.
• Filiform papillae – these are thin, longer taste buds, and are the most numerous. These papillae are mechanical and not involved in gustation.
• Foliate papillae – these are ridges and grooves towards the posterior part of the tongue.
• Vallate papillae – there are only about 3–14 of these taste buds on most people, and they are present at the back of the oral part of the tongue. They are arranged in a V-shaped row just in front of the sulcus terminalis of the tongue.

It is known that there are five types of taste buds corresponding to the following five taste sensations:

• Sweet, Bitter, and umami, which work with a signal through a G-protein coupled receptor.
• Salty and Sour, which work with ion channels.