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64-401: The human tongue is divided into two parts, an oral part at the front and a pharyngeal part at the back. The left and right sides are also separated along most of its length by a vertical section of fibrous tissue (the lingual septum ) that results in a groove, the median sulcus, on the tongue's surface. There are two groups of glossal muscles. The four intrinsic muscles alter the shape of

128-854: A metonym for language . For example, the New Testament of the Bible, in the Book of Acts of the Apostles , Jesus ' disciples on the Day of Pentecost received a type of spiritual gift : "there appeared unto them cloven tongues like as of fire, and it sat upon each of them. And they were all filled with the Holy Ghost , and began to speak with other tongues ....", which amazed the crowd of Jewish people in Jerusalem , who were from various parts of

192-486: A farmer from Fabriano , Italy, was convicted and fined by Italy's highest court for sticking his tongue out at a neighbor with whom he had been arguing - proof of the affront had been captured with a cell-phone camera. Tongue piercing and splitting have become more common in western countries in recent decades. One study found that one-fifth of young adults in Israel had at least one type of oral piercing, most commonly

256-429: A mouth and a one-way gut. Some modern invertebrates still have such a system: food being ingested through the mouth, partially broken down by enzymes secreted in the gut, and the resulting particles engulfed by the other cells in the gut lining. Indigestible waste is ejected through the mouth. In animals at least as complex as an earthworm , the embryo forms a dent on one side, the blastopore , which deepens to become

320-407: A nasofrontal hinge allowing the beak to open wider than would otherwise be possible. The exterior surface of beaks is composed of a thin, horny sheath of keratin . Nectar feeders such as hummingbirds have specially adapted brushy tongues for sucking up nectar from flowers. In mammals, the buccal cavity is typically roofed by the hard and soft palates , floored by the tongue and surrounded by

384-413: A patient suffering chest pain from angina pectoris . The muscles of the tongue evolved in amphibians from occipital somites . Most amphibians show a proper tongue after their metamorphosis . As a consequence, most tetrapod animals—amphibians, reptiles, birds, and mammals—have tongues (the frog family of pipids lack tongue). In mammals such as dogs and cats , the tongue is often used to clean

448-458: A range of mouthparts suited to their mode of feeding. These include mandibles, maxillae and labium and can be modified into suitable appendages for chewing, cutting, piercing, sponging and sucking. Decapods have six pairs of mouth appendages, one pair of mandibles, two pairs of maxillae and three of maxillipeds . Sea urchins have a set of five sharp calcareous plates, which are used as jaws and are known as Aristotle's lantern . In vertebrates,

512-403: A statement that is not to be taken entirely seriously – something said or done with subtle ironic or sarcastic humour. A tongue twister is a phrase very difficult to pronounce. Aside from being a medical condition , "tongue-tied" means being unable to say what you want due to confusion or restriction. The phrase "cat got your tongue" refers to when a person is speechless. To "bite one's tongue"

576-550: A two-opening gut tube with a mouth at one end and an anus at the other. Which end forms first in ontogeny is a criterion used to classify bilaterian animals into protostomes and deuterostomes . In the first multicellular animals , there was probably no mouth or gut and food particles were engulfed by the cells on the exterior surface by a process known as endocytosis . The particles became enclosed in vacuoles into which enzymes were secreted and digestion took place intracellularly . The digestive products were absorbed into

640-437: Is a phrase which describes holding back an opinion to avoid causing offence. A "slip of the tongue" refers to an unintentional utterance, such as a Freudian slip . The "gift of tongues" refers to when one is uncommonly gifted to be able to speak in a foreign language, often as a type of spiritual gift . Speaking in tongues is a common phrase used to describe glossolalia , which is to make smooth, language-resembling sounds that

704-421: Is a shallow groove that runs forward as a shallow groove in a V shape from the foramen cecum, forwards and outwards to the margins (borders) of the tongue. The terminal sulcus divides the tongue into a posterior pharyngeal part and an anterior oral part. The pharyngeal part is supplied by the glossopharyngeal nerve and the oral part is supplied by the lingual nerve (a branch of the mandibular branch (V3) of

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768-446: Is along the length of the tongue save for the very back of the pharyngeal part and is visible as a groove called the median sulcus. The human tongue is divided into anterior and posterior parts by the terminal sulcus, which is a "V"-shaped groove. The apex of the terminal sulcus is marked by a blind foramen, the foramen cecum, which is a remnant of the median thyroid diverticulum in early embryonic development . The anterior oral part

832-426: Is an important accessory organ in the digestive system. The tongue is used for crushing food against the hard palate, during mastication and manipulation of food for softening prior to swallowing. The epithelium on the tongue's upper, or dorsal surface is keratinised . Consequently, the tongue can grind against the hard palate without being itself damaged or irritated. The tongue is one of the primary articulators in

896-406: Is located exactly mid-line, between the anterior 2/3 and posterior 1/3 of the tongue . The thyroid gland starts developing in the oropharynx in the fetus and descends to its final position taking a path through the tongue, hyoid bone and neck muscles . The connection between its original position and its final position is the thyroglossal duct. This duct normally atrophies and closes off as

960-462: Is no true spoken language itself. A deceptive person is said to have a forked tongue , and a smooth-talking person is said to have a silver tongue . Sticking one's tongue out at someone is considered a childish gesture of rudeness or defiance in many countries; the act may also have sexual connotations, depending on the way in which it is done. However, in Tibet it is considered a greeting. In 2009,

1024-465: Is produced with the tongue lowered and centered and [i] is produced with the tongue raised and fronted . Consonants are articulated by constricting airflow through the vocal tract, and many consonants feature a constriction between the tongue and some other part of the vocal tract. For example, alveolar consonants like [s] and [n] are articulated with the tongue against the alveolar ridge , while velar consonants like [k] and [g] are articulated with

1088-498: Is the visible part situated at the front and makes up roughly two-thirds the length of the tongue. The posterior pharyngeal part is the part closest to the throat , roughly one-third of its length. These parts differ in terms of their embryological development and nerve supply . The anterior tongue is, at its apex, thin and narrow. It is directed forward against the lingual surfaces of the lower incisor teeth. The posterior part is, at its root, directed backward, and connected with

1152-596: The Roman Empire but could now understand what was being preached. The phrase mother tongue is used as a child's first language. Many languages have the same word for "tongue" and " language ", as did the English language before the Middle Ages . A common temporary failure in word retrieval from memory is referred to as the tip-of-the-tongue phenomenon . The expression tongue in cheek refers to

1216-445: The archenteron , the first phase in the formation of the gut . In deuterostomes, the blastopore becomes the anus while the gut eventually tunnels through to make another opening, which forms the mouth. In the protostomes, it used to be thought that the blastopore formed the mouth ( proto– meaning "first") while the anus formed later as an opening made by the other end of the gut. More recent research, however, shows that in protostomes

1280-466: The cheeks , salivary glands , and upper and lower teeth . The upper teeth are embedded in the upper jaw and the lower teeth in the lower jaw , which articulates with the temporal bones of the skull . The lips are soft and fleshy folds which shape the entrance into the mouth. The buccal cavity empties through the pharynx into the oesophagus . Crocodilians living in the tropics can gape with their mouths to provide cooling by evaporation from

1344-420: The hyoid bone by the hyoglossi and genioglossi muscles and the hyoglossal membrane , with the epiglottis by three glossoepiglottic folds of mucous membrane, with the soft palate by the glossopalatine arches , and with the pharynx by the superior pharyngeal constrictor muscle and the mucous membrane . It also forms the anterior wall of the oropharynx . The average length of the human tongue from

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1408-460: The internal jugular vein . The floor of the mouth also receives its blood supply from the lingual artery. There is also a secondary blood supply to the root of tongue from the tonsillar branch of the facial artery and the ascending pharyngeal artery . An area in the neck sometimes called the Pirogov triangle is formed by the intermediate tendon of the digastric muscle , the posterior border of

1472-439: The lips and cheeks — thus the oral cavity is also known as the buccal cavity (from Latin bucca , meaning "cheek") — and contains the tongue on the inside. Except for some groups like birds and lissamphibians , vertebrates usually have teeth in their mouths, although some fish species have pharyngeal teeth instead of oral teeth. Most bilaterian phyla , including arthropods , molluscs and chordates , have

1536-528: The mylohyoid muscle , and the hypoglossal nerve. The lingual artery is a good place to stop severe hemorrhage from the tongue. Innervation of the tongue consists of motor fibers, special sensory fibers for taste, and general sensory fibers for sensation. Innervation of taste and sensation is different for the anterior and posterior part of the tongue because they are derived from different embryological structures ( pharyngeal arch 1 and pharyngeal arches 3 and 4, respectively). The tip of tongue drains to

1600-417: The oropharynx to the tip is 10 cm. The average weight of the human tongue from adult males is 99g and for adult females 79g. In phonetics and phonology , a distinction is made between the tip of the tongue and the blade (the portion just behind the tip). Sounds made with the tongue tip are said to be apical , while those made with the tongue blade are said to be laminal . The upper surface of

1664-648: The palatoglossal fold towards the midline, and elevates the back of the tongue during swallowing. Four paired intrinsic muscles of the tongue originate and insert within the tongue, running along its length. They are the superior longitudinal muscle , the inferior longitudinal muscle , the vertical muscle , and the transverse muscle . These muscles alter the shape of the tongue by lengthening and shortening it, curling and uncurling its apex and edges as in tongue rolling , and flattening and rounding its surface. This provides shape and helps facilitate speech, swallowing, and eating. The superior longitudinal muscle runs along

1728-405: The syrinx . For each burst of song, the bird opens its beak and closes it again afterwards. The beak may move slightly and may contribute to the resonance but the song originates elsewhere. Thyroglossal duct The thyroglossal duct is an embryological anatomical structure forming an open connection between the initial area of development of the thyroid gland and its final position. It

1792-437: The taste buds and their taste receptors . The lingual papillae consist of filiform , fungiform , vallate and foliate papillae , and only the filiform papillae are not associated with any taste buds. The tongue can divide itself in dorsal and ventral surface. The dorsal surface is a stratified squamous keratinized epithelium, which is characterized by numerous mucosal projections called papillae. The lingual papillae covers

1856-449: The trigeminal nerve ) for somatosensory perception and by the chorda tympani (a branch of the facial nerve ) for taste perception . Both parts of the tongue develop from different pharyngeal arches . On the undersurface of the tongue is a fold of mucous membrane called the frenulum that tethers the tongue at the midline to the floor of the mouth. On either side of the frenulum are small prominences called sublingual caruncles that

1920-407: The airflow from the lungs in different ways and changes the mouth's resonating properties, producing a range of different sounds. In frogs, the sounds can be amplified using sacs in the throat region. The vocal sacs can be inflated and deflated and act as resonators to transfer the sound to the outside world. A bird's song is produced by the flow of air over a vocal organ at the base of the trachea ,

1984-441: The body. The oral mucosa is very thin underneath the tongue, and is underlain by a plexus of veins. The sublingual route takes advantage of the highly vascular quality of the oral cavity, and allows for the speedy application of medication into the cardiovascular system, bypassing the gastrointestinal tract. This is the only convenient and efficacious route of administration (apart from Intravenous therapy ) of nitroglycerin to

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2048-547: The cavity and it can gape widely enough to accommodate large prey items. Food passes first into a pharynx and digestion occurs extracellularly in the gastrovascular cavity . Annelids have simple tube-like guts, and the possession of an anus allows them to separate the digestion of their foodstuffs from the absorption of the nutrients. Many molluscs have a radula , which is used to scrape microscopic particles off surfaces. In invertebrates with hard exoskeletons, various mouthparts may be involved in feeding behaviour. Insects have

2112-566: The cytoplasm and diffused into other cells. This form of digestion is used nowadays by simple organisms such as Amoeba and Paramecium and also by sponges which, despite their large size, have no mouth or gut and capture their food by endocytosis. However, most animals have a mouth and a gut, the lining of which is continuous with the epithelial cells on the surface of the body. A few animals which live parasitically originally had guts but have secondarily lost these structures. The original gut of diploblastic animals probably consisted of

2176-411: The dog's mouth and the moisture on the tongue will work to cool the bloodflow. Some animals have tongues that are specially adapted for catching prey. For example, chameleons , frogs , pangolins and anteaters have prehensile tongues. Other animals may have organs that are analogous to tongues, such as a butterfly 's proboscis or a radula on a mollusc , but these are not homologous with

2240-401: The dorsal side of the tongue towards the front of the terminal groove. The ventral surface is stratified squamous non-keratinized epithelium which is smooth. The tongue begins to develop in the fourth week of embryonic development from a median swelling – the median tongue bud (tuberculum impar) of the first pharyngeal arch . In the fifth week a pair of lateral lingual swellings , one on

2304-475: The edges of the slit-like blastopore close up in the middle, leaving openings at both ends that become the mouth and anus. Apart from sponges and placozoans , almost all animals have an internal gut cavity, which is lined with gastrodermal cells. In less advanced invertebrates such as the sea anemone , the mouth also acts as an anus. Circular muscles around the mouth are able to relax or contract in order to open or close it. A fringe of tentacles thrusts food into

2368-609: The embryonic thyroid begins to descend. Chemicals that stimulate taste receptor cells are known as tastants . Once a tastant is dissolved in saliva , it can make contact with the plasma membrane of the gustatory hairs, which are the sites of taste transduction . The tongue is equipped with many taste buds on its dorsal surface, and each taste bud is equipped with taste receptor cells that can sense particular classes of tastes. Distinct types of taste receptor cells respectively detect substances that are sweet, bitter, salty, sour, spicy, or taste of umami . Umami receptor cells are

2432-473: The first part of the digestive system is the buccal cavity , commonly known as the mouth. The buccal cavity of a fish is separated from the opercular cavity by the gills . Water flows in through the mouth, passes over the gills and exits via the operculum or gill slits . Nearly all fish have jaws and may seize food with them but most feed by opening their jaws, expanding their pharynx and sucking in food items. The food may be held or chewed by teeth located in

2496-436: The fur and body by licking . The tongues of these species have a very rough texture, which allows them to remove oils and parasites. Some dogs have a tendency to consistently lick a part of their foreleg, which can result in a skin condition known as a lick granuloma . A dog's tongue also acts as a heat regulator. As a dog increases its exercise the tongue will increase in size due to greater blood flow. The tongue hangs out of

2560-420: The growth of endoderm from the third pharyngeal arch. The boundary between the two parts of the tongue, the anterior from the first arch and the posterior from the third arch is marked by the terminal sulcus. The terminal sulcus is shaped like a V with the tip of the V situated posteriorly. At the tip of the terminal sulcus is the foramen cecum , which is the point of attachment of the thyroglossal duct where

2624-433: The jaws, on the roof of the mouth, on the pharynx or on the gill arches . Nearly all amphibians are carnivorous as adults. Many catch their prey by flicking out an elongated tongue with a sticky tip and drawing it back into the mouth, where they hold the prey with their jaws. They then swallow their food whole without much chewing. They typically have many small hinged pedicellate teeth , the bases of which are attached to

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2688-755: The jaws, while the crowns break off at intervals and are replaced. Most amphibians have one or two rows of teeth in both jaws but some frogs lack teeth in the lower jaw. In many amphibians, there are also vomerine teeth attached to the bone in the roof of the mouth. The mouths of reptiles are largely similar to those of mammals. The crocodilians are the only reptiles to have teeth anchored in sockets in their jaws. They are able to replace each of their approximately 80 teeth up to 50 times during their lives. Most reptiles are either carnivorous or insectivorous, but turtles are often herbivorous. Lacking teeth that are suitable for efficiently chewing of their food, turtles often have gastroliths in their stomach to further grind

2752-430: The least understood and accordingly are the type most intensively under research. There is a common misconception that different sections of the tongue are exclusively responsible for different basic tastes . Although widely taught in schools in the form of the tongue map , this is incorrect; all taste sensations come from all regions of the tongue, although certain parts are more sensitive to certain tastes. The tongue

2816-404: The major salivary submandibular glands drain into. The eight muscles of the human tongue are classified as either intrinsic or extrinsic . The four intrinsic muscles act to change the shape of the tongue, and are not attached to any bone. The four extrinsic muscles act to change the position of the tongue, and are anchored to bone. The four extrinsic muscles originate from bone and extend to

2880-405: The mechanism for producing sounds for communication. To produce sounds, air is forced from the lungs over vocal cords in the larynx. In humans, the pharynx, soft palate, hard palate, alveolar ridge , tongue, teeth and lips are termed articulators and play their part in the production of speech . Varying the position of the tongue in relation to the other articulators or moving the lips restricts

2944-445: The middle of the tongue, and joins the superior and inferior longitudinal muscles. It functions to flatten the tongue. The transverse muscle divides the tongue at the middle, and is attached to the mucous membranes that run along the sides. It functions to lengthen and narrow the tongue. The tongue receives its blood supply primarily from the lingual artery , a branch of the external carotid artery . The lingual veins drain into

3008-419: The mouth lining. Some mammals rely on panting for thermoregulation as it increases evaporation of water across the moist surfaces of the lungs, the tongue and mouth. Birds also avoid overheating by gular fluttering, flapping the wings near the gular (throat) skin, similar to panting in mammals. Various animals use their mouths in threat displays. They may gape widely, exhibit their teeth prominently, or flash

3072-517: The plant material. Snakes have a very flexible lower jaw, the two halves of which are not rigidly attached, and numerous other joints in their skull. These modifications allow them to open their mouths wide enough to swallow their prey whole, even if it is wider than they are. Birds do not have teeth, relying instead on other means of gripping and macerating their food. Their beaks have a range of sizes and shapes according to their diet and are composed of elongated mandibles. The upper mandible may have

3136-472: The production of speech , and this is facilitated by both the extrinsic muscles that move the tongue and the intrinsic muscles that change its shape. Specifically, different vowels are articulated by changing the tongue's height and retraction to alter the resonant properties of the vocal tract . These resonant properties amplify specific harmonic frequencies ( formants ) that are different for each vowel, while attenuating other harmonics. For example, [a]

3200-399: The right side and one on the left, form on the first pharyngeal arch. These lingual swellings quickly expand and cover the median tongue bud. They form the anterior part of the tongue that makes up two-thirds of the length of the tongue, and continue to develop through prenatal development . The line of their fusion is marked by the median sulcus . In the fourth week, a swelling appears from

3264-447: The second pharyngeal arch , in the midline, called the copula . During the fifth and sixth weeks, the copula is overgrown by a swelling from the third and fourth arches (mainly from the third arch) called the hypopharyngeal eminence , and this develops into the posterior part of the tongue (the other third and the posterior most part of the tongue is developed from the fourth pharyngeal arch). The hypopharyngeal eminence develops mainly by

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3328-419: The startling colours of the mouth lining. This display allows each potential combatant an opportunity to assess the weapons of their opponent and lessens the likelihood of actual combat being necessary. A number of species of bird use a gaping , open beak in their fear and threat displays. Some augment the display by hissing or breathing heavily, while others clap their beaks. Mouths are also used as part of

3392-422: The submental nodes. The left and right halves of the anterior two-thirds of the tongue drains to submandibular lymph nodes , while the posterior one-third of the tongue drains to the jugulo-omohyoid nodes. The upper surface of the tongue is covered in masticatory mucosa , a type of oral mucosa , which is of keratinized stratified squamous epithelium . Embedded in this are numerous papillae , some of which house

3456-821: The tongue and are not attached to bone. The four paired extrinsic muscles change the position of the tongue and are anchored to bone. The word tongue derives from the Old English tunge , which comes from Proto-Germanic * tungōn . It has cognates in other Germanic languages —for example tonge in West Frisian , tong in Dutch and Afrikaans , Zunge in German , tunge in Danish and Norwegian , and tunga in Icelandic , Faroese and Swedish . The ue ending of

3520-474: The tongue dorsum against the soft palate (velum). Tongue shape is also relevant to speech articulation, for example in retroflex consonants , where the tip of the tongue is curved backward. The tongue plays a role in physical intimacy and sexuality . The tongue is part of the erogenous zone of the mouth and can be used in intimate contact, as in the French kiss and in oral sex . A congenital disorder of

3584-407: The tongue forward. The hyoglossus, arises from the hyoid bone and retracts and depresses the tongue. The chondroglossus is often included with this muscle. The styloglossus arises from the styloid process of the temporal bone and draws the sides of the tongue up to create a trough for swallowing. The palatoglossus arises from the palatine aponeurosis , and depresses the soft palate , moves

3648-443: The tongue is called the dorsum, and is divided by a groove into symmetrical halves by the median sulcus . The foramen cecum marks the end of this division (at about 2.5 cm from the root of the tongue) and the beginning of the terminal sulcus . The foramen cecum is also the point of attachment of the thyroglossal duct and is formed during the descent of the thyroid diverticulum in embryonic development . The terminal sulcus

3712-637: The tongue is that of ankyloglossia also known as tongue-tie . The tongue is tied to the floor of the mouth by a very short and thickened frenulum and this affects speech, eating, and swallowing. The tongue is prone to several pathologies including glossitis and other inflammations such as geographic tongue , and median rhomboid glossitis ; burning mouth syndrome , oral hairy leukoplakia , oral candidiasis (thrush), black hairy tongue , bifid tongue (due to failure in fusion of two lingual swellings of first pharyngeal arch) and fissured tongue . There are several types of oral cancer that mainly affect

3776-461: The tongue. Oral cavity The mouth is the body orifice through which many animals ingest food and vocalize . The body cavity immediately behind the mouth opening, known as the oral cavity (or cavum oris in Latin ), is also the first part of the alimentary canal , which leads to the pharynx and the gullet . In tetrapod vertebrates , the mouth is bounded on the outside by

3840-434: The tongue. Mostly these are squamous cell carcinomas . Food debris, desquamated epithelial cells and bacteria often form a visible tongue coating. This coating has been identified as a major factor contributing to bad breath (halitosis), which can be managed by using a tongue cleaner . The sublingual region underneath the front of the tongue is an ideal location for the administration of certain medications into

3904-423: The tongue. They are the genioglossus , the hyoglossus (often including the chondroglossus ) the styloglossus , and the palatoglossus . Their main functions are altering the tongue's position allowing for protrusion, retraction, and side-to-side movement. The genioglossus arises from the mandible and protrudes the tongue. It is also known as the tongue's "safety muscle" since it is the only muscle that propels

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3968-465: The tongues found in vertebrates and often have little resemblance in function. For example, butterflies do not lick with their proboscides; they suck through them, and the proboscis is not a single organ, but two jaws held together to form a tube. Many species of fish have small folds at the base of their mouths that might informally be called tongues, but they lack a muscular structure like the true tongues found in most tetrapods . The tongue can serve as

4032-399: The upper surface of the tongue under the mucous membrane, and functions to shorten and curl the tongue upward. It originates near the epiglottis , at the hyoid bone , from the median fibrous septum. The inferior longitudinal muscle lines the sides of the tongue, and is joined to the styloglossus muscle. It functions to shorten and curl the tongue downward. The vertical muscle is located in

4096-433: The word seems to be a fourteenth-century attempt to show "proper pronunciation", but it is "neither etymological nor phonetic". Some used the spelling tunge and tonge as late as the sixteenth century. The tongue is a muscular hydrostat that forms part of the floor of the oral cavity . The left and right sides of the tongue are separated by a vertical section of fibrous tissue known as the lingual septum . This division

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