Taste buds on the tongue are example of:

Explanation

The taste receptors are located around the small structures known as papillae found on the upper surface of the tongue; these are chemoreceptors. Taste receptors are proteins located on taste receptor cells within taste buds that bind to chemical compounds in food, initiating signals that the brain interprets as the basic tastes: sweet, salty, sour, bitter, and umami. These receptors are located on the microvilli that project from the taste cells into the taste pore, where they interact with food molecules, ultimately transmitting taste information to the brain via nerves.