taste bud

taste bud
one of numerous small, flask-shaped bodies, chiefly in the epithelium of the tongue, which are the end organs for the sense of taste.
[1885-90]

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 small organ located on the tongue in terrestrial vertebrates (vertebrate) that functions in the perception of taste. In fish, taste buds occur on the lips, the flanks, and the caudal (tail) fins of some species and on the barbels of catfish.

      Taste receptor cells (cell), with which incoming chemicals from food and other sources interact, occur on the tongue in groups of 50–150. Each of these groups forms a taste bud, which is grouped together with other taste buds into taste papillae. The taste buds are embedded in the epithelium of the tongue and make contact with the outside environment through a taste pore. Slender processes (microvilli) extend from the outer ends of the receptor cells through the taste pore, where the processes are covered by the mucus that lines the oral cavity. At their inner ends the taste receptor cells synapse, or connect, with afferent sensory neurons (neuron), nerve cells that conduct information to the brain. Each receptor cell synapses with several afferent sensory neurons, and each afferent neuron branches to several taste papillae, where each branch makes contact with many receptor cells. The afferent sensory neurons occur in three different nerves running to the brain—the facial nerve, the glossopharyngeal nerve, and the vagus nerve. Taste receptor cells of vertebrates are continually renewed throughout the life of the organism.

      On average, the human tongue has 2,000–8,000 taste buds, implying that there are hundreds of thousands of receptor cells. However, the number of taste buds varies widely. For example, per square centimetre on the tip of the tongue, some people may have only a few individual taste buds, whereas others may have more than one thousand; this variability contributes to differences in the taste sensations experienced by different people. Taste sensations produced within an individual taste bud also vary, since each taste bud typically contains receptor cells that respond to distinct chemical stimuli—as opposed to the same chemical stimulus. As a result, the sensation of different tastes (i.e., salty, sweet, sour, bitter, or umami) is diverse not only within a single taste bud but also throughout the surface of the tongue.

      The taste receptor cells of other animals can often be characterized in ways similar to those of humans, because all animals have the same basic needs in selecting food.

Elizabeth Bernays Reginald Chapman
 

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Universalium. 2010.

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Look at other dictionaries:

  • taste bud — n an end organ that mediates the sensation of taste, lies chiefly in the epithelium of the tongue and esp. in the walls of the circumvallate papillae, and consists of a conical or flask shaped mass made up partly of supporting cells and partly of …   Medical dictionary

  • taste bud — n [C usually plural] one of the small parts of the surface of your tongue with which you can taste things …   Dictionary of contemporary English

  • taste bud — taste′ bud n. anat. one of numerous small flask shaped bodies, chiefly in the epithelium of the tongue, that are the sense organs of taste …   From formal English to slang

  • taste bud — ► NOUN ▪ any of the clusters of nerve endings on the tongue and in the lining of the mouth which provide the sense of taste …   English terms dictionary

  • taste bud — n. an oval cluster of cells embedded principally in the epithelium of the tongue and functioning as the sense organ of taste …   English World dictionary

  • Taste bud — Infobox Anatomy Name = Taste bud Latin = caliculus gustatorius GraySubject = 222 GrayPage = 991 Caption = Semidiagrammatic view of a portion of the mucous membrane of the tongue. Two fungiform papillæ are shown. On some of the filiform papillæ… …   Wikipedia

  • taste bud — noun an oval sensory end organ on the surface of the tongue • Syn: ↑tastebud, ↑gustatory organ • Hypernyms: ↑chemoreceptor • Part Holonyms: ↑tongue, ↑lingua, ↑ …   Useful english dictionary

  • taste bud — taste buds also tastebud N COUNT: usu pl, oft poss N Your taste buds are the little points on the surface of your tongue which enable you to recognize the flavour of a food or drink …   English dictionary

  • taste bud — noun Date: 1879 an end organ mediating the sensation of taste and lying chiefly in the epithelium of the tongue …   New Collegiate Dictionary

  • taste bud — (ARTHROPODA: Insecta) In Lepidoptera, specialized taste cells located on the tarsi …   Dictionary of invertebrate zoology

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