The tongue is a
muscular
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...
organ in the
mouth of a typical
tetrapod
Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids ( pelycosaurs, extinct t ...
. It manipulates food for
mastication and
swallowing as part of the
digestive process, and is the primary organ of
taste
The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor). Taste is the perception produced or stimulated when a substance in the mouth reacts chemically with taste receptor ...
. The tongue's upper surface (dorsum) is covered by
taste buds
Taste buds contain the taste receptor cells, which are also known as gustatory cells. The taste receptors are located around the small structures known as papillae found on the upper surface of the tongue, soft palate, upper esophagus, the che ...
housed in numerous
lingual papilla
Lingual papillae (singular papilla) are small structures on the upper surface of the tongue that give it its characteristic rough texture. The four types of papillae on the human tongue have different structures and are accordingly classified as c ...
e. It is sensitive and kept moist by
saliva and is richly supplied with
nerves and
blood vessel
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...
s. The tongue also serves as a natural means of
cleaning
Cleaning is the process of removing unwanted substances, such as dirt, infectious agents, and other impurities, from an object or environment. Cleaning is often performed for aesthetic, hygienic, functional, environmental, or safety purposes ...
the teeth. A major function of the tongue is the enabling of
speech in
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...
s and
vocalization in other animals.
The human tongue is divided into two parts, an
oral
The word oral may refer to:
Relating to the mouth
* Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid
**Oral administration of medicines
** Oral examination (also known as an oral exam or or ...
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
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
(the
lingual septum
The lingual septum consists of a vertical layer of fibrous tissue, extending throughout the entire length of the median plane of the tongue, though not quite reaching the dorsum. The lingual septum is closely associated with the hyoglossus membr ...
) that results in a groove, the median sulcus, on the tongue's surface.
There are two groups of muscles of the tongue. The four intrinsic muscles alter the shape of the tongue and are not attached to bone. The four paired extrinsic muscles change the position of the tongue and are anchored to bone.
Etymology
The word tongue derives from the
Old English
Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers in the mid-5th c ...
''tunge'', which comes from
Proto-Germanic
Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages.
Proto-Germanic eventually developed from pre-Proto-Germanic into three Germanic bran ...
*''tungōn''.
It has
cognates
In historical linguistics, cognates or lexical cognates are sets of words in different languages that have been inherited in direct descent from an etymological ancestor in a common parent language. Because language change can have radical eff ...
in other
Germanic languages
The Germanic languages are a branch of the Indo-European language family spoken natively by a population of about 515 million people mainly in Europe, North America, Oceania and Southern Africa. The most widely spoken Germanic language, E ...
—for example ''tonge'' in
West Frisian, ''tong'' in
Dutch
Dutch commonly refers to:
* Something of, from, or related to the Netherlands
* Dutch people ()
* Dutch language ()
Dutch may also refer to:
Places
* Dutch, West Virginia, a community in the United States
* Pennsylvania Dutch Country
People E ...
and
Afrikaans
Afrikaans (, ) is a West Germanic language that evolved in the Dutch Cape Colony from the Dutch vernacular of Holland proper (i.e., the Hollandic dialect) used by Dutch, French, and German settlers and their enslaved people. Afrikaans gra ...
, ''Zunge'' in
German
German(s) may refer to:
* Germany (of or related to)
** Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ge ...
, ''tunge'' in
Danish
Danish may refer to:
* Something of, from, or related to the country of Denmark
People
* A national or citizen of Denmark, also called a "Dane," see Demographics of Denmark
* Culture of Denmark
* Danish people or Danes, people with a Danish a ...
and
Norwegian
Norwegian, Norwayan, or Norsk may refer to:
*Something of, from, or related to Norway, a country in northwestern Europe
* Norwegians, both a nation and an ethnic group native to Norway
* Demographics of Norway
*The Norwegian language, including ...
, and ''tunga'' in
Icelandic,
Faroese and
Swedish
Swedish or ' may refer to:
Anything from or related to Sweden, a country in Northern Europe. Or, specifically:
* Swedish language, a North Germanic language spoken primarily in Sweden and Finland
** Swedish alphabet, the official alphabet used by ...
. The ''ue'' ending of 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.
In humans
Structure
![Facies inferior linguae](https://upload.wikimedia.org/wikipedia/commons/5/58/Facies_inferior_linguae.JPG)
The tongue is a
muscular hydrostat
A muscular hydrostat is a biological structure found in animals. It is used to manipulate items (including food) or to move its host about and consists mainly of muscles with no skeletal support. It performs its hydraulic movement without fluid in ...
that forms part of the floor of the
oral cavity
In animal anatomy, the mouth, also known as the oral cavity, or in Latin cavum oris, is the opening through which many animals take in food and issue vocal sounds. It is also the cavity lying at the upper end of the alimentary canal, bounded on t ...
. The left and right sides of the tongue are separated by a vertical section of fibrous tissue known as the
lingual septum
The lingual septum consists of a vertical layer of fibrous tissue, extending throughout the entire length of the median plane of the tongue, though not quite reaching the dorsum. The lingual septum is closely associated with the hyoglossus membr ...
. This division 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
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position p ...
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 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
In vertebrate anatomy, the throat is the front part of the neck, internally positioned in front of the vertebrae. It contains the pharynx and larynx. An important section of it is the epiglottis, separating the esophagus from the trachea (windpip ...
, 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
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...
teeth. The posterior part is, at its root, directed backward, and connected with the
hyoid bone by the
hyoglossi
The hyoglossus, thin and quadrilateral, arises from the side of the body and from the whole length of the greater cornu of the hyoid bone, and passes almost vertically upward to enter the side of the tongue, between the styloglossus and the infer ...
and
genioglossi
The genioglossus is one of the paired extrinsic muscles of the tongue. The genioglossus is the major muscle responsible for protruding (or sticking out) the tongue.
Structure
Genioglossus is the fan-shaped extrinsic tongue muscle that forms the ma ...
muscles and the
hyoglossal membrane
The hyoglossal membrane is a strong fibrous lamina, which connects the under surface of the root of the tongue to the body of the hyoid bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior mid ...
, with the
epiglottis
The epiglottis is a leaf-shaped flap in the throat that prevents food and water from entering the trachea and the lungs. It stays open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration of food in ...
by three
glossoepiglottic folds
The anterior or lingual surface of the epiglottis is curved forward, and covered on its upper, free part by mucous membrane which is reflected on to the sides and root of the tongue, forming a median and two lateral glossoepiglottic folds; the late ...
of mucous membrane, with the
soft palate
The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...
by the
glossopalatine arches
The palatoglossal arch (glossopalatine arch, anterior pillar of fauces) on either side runs downward, lateral (to the side), and forward to the side of the base of the tongue, and is formed by the projection of the glossopalatine muscle with its c ...
, and with the
pharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its st ...
by the
superior pharyngeal constrictor muscle and the
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It i ...
. It also forms the anterior wall of the
oropharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...
.
The average length of the human tongue from the
oropharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...
to the tip is 10 cm. The average weight of the human tongue from adult males is 70g and for adult females 60g.
In
phonetics
Phonetics is a branch of linguistics that studies how humans produce and perceive sounds, or in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians. ...
and
phonology
Phonology is the branch of linguistics that studies how languages or dialects systematically organize their sounds or, for sign languages, their constituent parts of signs. The term can also refer specifically to the sound or sign system of a ...
, 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
Apical means "pertaining to an apex". It may refer to:
*Apical ancestor, refers to the last common ancestor of an entire group, such as a species (biology) or a clan (anthropology)
*Apical (anatomy), an anatomical term of location for features loc ...
, while those made with the tongue blade are said to be
laminal
A laminal consonant is a phone (speech sound) produced by obstructing the air passage with the blade of the tongue, the flat top front surface just behind the tip of the tongue in contact
with upper lip, teeth, alveolar ridge, to possibly, as ...
.
Upper surface of the tongue
![Tongue](https://upload.wikimedia.org/wikipedia/commons/2/22/Tongue.svg)
The upper surface of 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
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 is located exactly mid-line, between the anterior 2/3 and posterior ...
and is formed during the descent of the
thyroid diverticulum in
embryonic development.
The terminal sulcus 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
The word oral may refer to:
Relating to the mouth
* Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid
**Oral administration of medicines
** Oral examination (also known as an oral exam or or ...
part. The pharyngeal part is supplied by the
glossopharyngeal nerve
The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. ...
and the oral part is supplied by the
lingual nerve
The lingual nerve carries sensory innervation from the anterior two-thirds of the tongue. It contains fibres from both the mandibular division of the trigeminal nerve (CN V3
) and from the facial nerve (CN VII). The fibres from the trigeminal nerv ...
(a branch of the mandibular branch (V3) of the
trigeminal nerve
In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chew ...
) for somatosensory perception and by the
chorda tympani
The chorda tympani is a branch of the facial nerve that originates from the taste buds in the front of the tongue, runs through the middle ear, and carries taste messages to the brain. It joins the facial nerve (cranial nerve VII) inside the fa ...
(a branch of the
facial nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste ...
) for
taste perception.
Both parts of the tongue develop from different
pharyngeal arch
The pharyngeal arches, also known as visceral arches'','' are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arche ...
es.
Undersurface of the tongue
On the undersurface of the tongue is a fold of mucous membrane called the
frenulum
A frenulum (or frenum, plural: frenula or frena, from the Latin ''frēnulum'', "little bridle", the diminutive of ''frēnum'') is a small fold of tissue that secures the motion of a mobile organ in the body.
In human anatomy
Frenula on the h ...
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 the major salivary
submandibular gland
The paired submandibular glands (historically known as submaxillary glands) are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimula ...
s drain into.
Muscles
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.
=Extrinsic
=
![Hyoglossus](https://upload.wikimedia.org/wikipedia/commons/7/7e/Hyoglossus.png)
The four extrinsic muscles originate from bone and extend to the tongue. They are the
genioglossus
The genioglossus is one of the paired extrinsic muscles of the tongue. The genioglossus is the major muscle responsible for protruding (or sticking out) the tongue.
Structure
Genioglossus is the fan-shaped extrinsic tongue muscle that forms the ma ...
, the
hyoglossus
The hyoglossus, thin and quadrilateral, arises from the side of the body and from the whole length of the greater cornu of the hyoid bone, and passes almost vertically upward to enter the side of the tongue, between the styloglossus and the infe ...
(often including the
chondroglossus) the
styloglossus
The styloglossus, the shortest and smallest of the three styloid muscles, arises from the anterior and lateral surfaces of the styloid process near its apex, and from the stylomandibular ligament.
Passing inferiorly and anteriorly between the int ...
, and the
palatoglossus
The palatoglossus or palatoglossal muscle is a muscle of the soft palate and extrinsic muscle of the tongue. Its surface is covered by oral mucosa and forms the visible palatoglossal arch.
Structure
Palatoglossus arises from the palatine aponeur ...
. Their main functions are altering the tongue's position allowing for protrusion, retraction, and side-to-side movement.
The genioglossus arises from the
mandible
In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movabl ...
and protrudes the tongue. It is also known as the tongue's "safety muscle" since it is the only muscle that propels 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
The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex.
The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. Th ...
and draws the sides of the tongue up to create a trough for swallowing.
The palatoglossus arises from the
palatine aponeurosis
Attached to the posterior border of the hard palate is a thin, firm, fibrous lamella called the palatine aponeurosis, which supports the muscles and gives strength to the soft palate.
It is thicker above and narrows on the way down where it becom ...
, and depresses the
soft palate
The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...
, moves the ''palatoglossal fold'' towards the midline, and elevates the back of the tongue during swallowing.
=Intrinsic
=
![Gray1020](https://upload.wikimedia.org/wikipedia/commons/d/d8/Gray1020.png)
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 inferior longitudinal muscle of tongue is an intrinsic muscle of the tongue. It is situated on the under surface of the tongue between the genioglossus and hyoglossus. It helps to move the tongue.
Structure
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
Tongue rolling is the ability to roll the lateral edges of the tongue upwards into a tube. The tongue's intrinsic muscles allow some people to form their tongues into specific shapes. Rolling the tongue into a tube shape is often described as a ...
, and flattening and rounding its surface. This provides shape and helps facilitate speech, swallowing, and eating.
The superior longitudinal muscle runs along the upper surface of the tongue under the mucous membrane, and elevates, assists in retraction of, or deviates the tip of the tongue. It originates near the
epiglottis
The epiglottis is a leaf-shaped flap in the throat that prevents food and water from entering the trachea and the lungs. It stays open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration of food in ...
, 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.
The vertical muscle is located in the middle of the tongue, and joins the superior and inferior longitudinal muscles.
The transverse muscle divides the tongue at the middle, and is attached to the
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It i ...
s that run along the sides.
Blood supply
![Gray559](https://upload.wikimedia.org/wikipedia/commons/7/7a/Gray559.png)
The tongue receives its
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the c ...
supply primarily from the
lingual artery
The lingual artery arises from the external carotid artery between the superior thyroid artery and facial artery. It can be located easily in the tongue.
Structure
The lingual artery first branches off from the external carotid artery. It runs ob ...
, a branch of the
external carotid artery
The external carotid artery is a major artery of the head and neck. It arises from the common carotid artery when it splits into the external and internal carotid artery. External carotid artery supplies blood to the face and neck.
Structure
T ...
. The
lingual veins
The lingual veins begin on the dorsum, sides, and under surface of the tongue, and, passing backward along the course of the lingual artery, end in the internal jugular vein.
The vena comitans of the hypoglossal nerve (ranine vein), a branch of co ...
drain into the
internal jugular vein
The internal jugular vein is a paired jugular vein that collects blood from the brain and the superficial parts of the face and neck. This vein runs in the carotid sheath with the common carotid artery and vagus nerve.
It begins in the posteri ...
. 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
The tonsillar branch of the facial artery ascends between the pterygoideus internus and styloglossus muscles, and then along the side of the pharynx, perforating the constrictor pharyngis superior, to ramify in the substance of the palatine tonsil ...
and the
ascending pharyngeal artery
The ascending pharyngeal artery is an artery in the neck that supplies the pharynx, developing from the proximal part of the embryonic second aortic arch.
It is the smallest branch of the external carotid and is a long, slender vessel, deeply sea ...
.
An area in the neck sometimes called the
Pirogov triangle The Pirogov triangle (also Piragoff's triangle) is an area in the human neck formed by the intermediate tendon of the digastric muscle, the posterior border of the mylohyoid muscle, and the hypoglossal nerve. The triangle was named after Russian sur ...
is formed by the intermediate tendon of the
digastric muscle
The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') is a small muscle located under the jaw. The term "digastric muscle" refers to this specific muscle. However, other muscles that have two separate muscle bellie ...
, the posterior border of the
mylohyoid muscle
The mylohyoid muscle or diaphragma oris is a paired muscle of the neck. It runs from the mandible to the hyoid bone, forming the floor of the oral cavity of the mouth. It is named after its two attachments near the molar teeth. It forms the floor ...
, and the
hypoglossal
The hypoglossal nerve, also known as the twelfth cranial nerve, cranial nerve XII, or simply CN XII, is a cranial nerve that innervates all the extrinsic and intrinsic muscles of the tongue except for the palatoglossus, which is innervated by ...
nerve. The lingual artery is a good place to stop severe
hemorrhage
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
from the tongue.
Nerve supply
Innervation of the tongue consists of motor fibers,
special sensory fibers for taste, and
general sensory fibers for sensation.
* Motor supply for all intrinsic and extrinsic muscles of the tongue is supplied by
efferent motor nerve fibers from the
hypoglossal nerve
The hypoglossal nerve, also known as the twelfth cranial nerve, cranial nerve XII, or simply CN XII, is a cranial nerve that innervates all the extrinsic and intrinsic muscles of the tongue except for the palatoglossus, which is innervated by ...
(CN XII), with the exception of the
palatoglossus
The palatoglossus or palatoglossal muscle is a muscle of the soft palate and extrinsic muscle of the tongue. Its surface is covered by oral mucosa and forms the visible palatoglossal arch.
Structure
Palatoglossus arises from the palatine aponeur ...
, which is innervated by the
vagus nerve
The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...
(CN X).
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
The pharyngeal arches, also known as visceral arches'','' are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arche ...
1 and pharyngeal arches 3 and 4, respectively).
* Anterior two-thirds of tongue (anterior to the
vallate papillae
Lingual papillae (singular papilla) are small structures on the upper surface of the tongue that give it its characteristic rough texture. The four types of papillae on the human tongue have different structures and are accordingly classified as c ...
):
** Taste: chorda tympani branch of the
facial nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste ...
(CN VII) via
special visceral afferent A Special visceral afferent fibers (SVA) is a afferent fiber that develop in association with the gastrointestinal tract. They carry the special senses of smell (olfaction) and taste (gustation). The cranial nerves containing SVA fibers are the olfa ...
fibers
** Sensation: lingual branch of the mandibular (V3) division of the
trigeminal nerve
In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chew ...
(CN V) via
general visceral afferent
The general visceral afferent (GVA) fibers conduct sensory impulses (usually pain or reflex sensations) from the internal organs, glands, and blood vessels to the central nervous system. They are considered to be part of the visceral nervous sy ...
fibers
* Posterior one third of tongue:
** Taste and sensation:
glossopharyngeal nerve
The glossopharyngeal nerve (), also known as the ninth cranial nerve, cranial nerve IX, or simply CN IX, is a cranial nerve that exits the brainstem from the sides of the upper medulla, just anterior (closer to the nose) to the vagus nerve. ...
(CN IX) via a mixture of special and general visceral afferent fibers
* Base of tongue
** Taste and sensation: internal branch of the
superior laryngeal nerve
The superior laryngeal nerve is a branch of the vagus nerve. It arises from the middle of the inferior ganglion of vagus nerve and in its course receives a branch from the superior cervical ganglion of the sympathetic nervous system.
The superi ...
(itself a branch of the
vagus nerve
The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and right ...
, CN X)
Lymphatic drainage
The tip of tongue drains to the submental nodes. The left and right halves of the anterior two-thirds of the tongue drains to
submandibular lymph nodes
The submandibular lymph nodes (submaxillary glands in older texts), three to six in number, are lymph nodes beneath the body of the mandible in the submandibular triangle, and rest on the superficial surface of the submandibular gland.
One gland, ...
, while the posterior one-third of the tongue drains to the jugulo-omohyoid nodes.
Microanatomy
![Human tongue (251 09) Section](https://upload.wikimedia.org/wikipedia/commons/8/8a/Human_tongue_%28251_09%29_Section.jpg)
The upper surface of the tongue is covered in
masticatory mucosa, a type of
oral mucosa
The oral mucosa is the mucous membrane lining the inside of the mouth. It comprises stratified squamous epithelium, termed "oral epithelium", and an underlying connective tissue termed ''lamina propria''. The oral cavity has sometimes been descri ...
which is of
keratinized stratified squamous epithelium. Embedded in this are numerous
papillae, some of which house the
taste bud
Taste buds contain the taste receptor cells, which are also known as gustatory cells. The taste receptors are located around the small structures known as lingual papillae, papillae found on the upper surface of the tongue, soft palate, upper e ...
s and their
taste receptor
A taste receptor or tastant is a type of cellular receptor which facilitates the sensation of taste. When food or other substances enter the mouth, molecules interact with saliva and are bound to taste receptors in the oral cavity and other locat ...
s. The lingual papillae consist of
filiform
Filiform, thread or filament like, can refer to:
* Filiform, a common term used in botany to describe a thread-like shape
*Filiform, or filiform catheter
In medicine, a catheter (/ˈkæθətər/) is a thin tubing (material), tube made from m ...
,
fungiform,
vallate and
foliate papillae
Lingual papillae (singular papilla) are small structures on the upper surface of the tongue that give it its characteristic rough texture. The four types of papillae on the human tongue have different structures and are accordingly classified as c ...
,
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 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.
Development
![Gray979](https://upload.wikimedia.org/wikipedia/commons/5/5c/Gray979.png)
The tongue begins to develop in the fourth week of
embryonic development
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm ...
from a median swelling – the
median tongue bud
The median tongue bud (also tuberculum impar) marks the beginning of the development of the tongue. It appears as a midline swelling from the first pharyngeal arch late in the fourth week of embryogenesis. In the fifth week, a pair of lateral li ...
(tuberculum impar) of the
first pharyngeal arch
The pharyngeal arches, also known as visceral arches'','' are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arch ...
.
In the fifth week a pair of lateral lingual swellings, one on 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
Prenatal development () includes the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization, in the germinal stage of embryonic development, and continues in fetal devel ...
. The line of their fusion is marked by the
median sulcus.
[
In the fourth week a swelling appears from the second ]pharyngeal arch
The pharyngeal arches, also known as visceral arches'','' are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arche ...
, 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
The hypopharyngeal eminence or hypobranchial eminence is a midline swelling of the third and fourth pharyngeal arches, in the development of the tongue
The tongue is a muscular organ in the mouth of a typical tetrapod. It manipulates food for ...
, 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 the growth of endoderm
Endoderm is the innermost of the three primary germ layers in the very early embryo. The other two layers are the ectoderm (outside layer) and mesoderm (middle layer). Cells migrating inward along the archenteron form the inner layer of the gast ...
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
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 is located exactly mid-line, between the anterior 2/3 and posterior ...
where the embryonic thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...
begins to descend.
Function
Taste
Chemicals that stimulate taste receptor
A taste receptor or tastant is a type of cellular receptor which facilitates the sensation of taste. When food or other substances enter the mouth, molecules interact with saliva and are bound to taste receptors in the oral cavity and other locat ...
cells are known as tastants. Once a tastant is dissolved in saliva, it can make contact with the plasma membrane
The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (t ...
of the gustatory hairs, which are the sites of taste transduction.
The tongue is equipped with many taste buds
Taste buds contain the taste receptor cells, which are also known as gustatory cells. The taste receptors are located around the small structures known as papillae found on the upper surface of the tongue, soft palate, upper esophagus, the che ...
on its dorsal
Dorsal (from Latin ''dorsum'' ‘back’) may refer to:
* Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism
* Dorsal, positioned on top of an aircraft's fuselage
* Dorsal co ...
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 ( from ja, 旨味 ), or savoriness, is one of the five basic tastes. It has been described as savory and is characteristic of broths and cooked meats.
People taste umami through taste receptors that typically respond to glutamates and ...
. Umami receptor cells are the least understood and accordingly are the type most intensively under research. Tongue map
The tongue map or taste map is a common misconception that different sections of the tongue are exclusively responsible for different basic tastes. It is illustrated with a schematic map of the tongue, with certain parts of the tongue labeled for ...
is a myth that is widely taught in schools.
Mastication
The tongue 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
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellul ...
on the tongue's upper, or dorsal surface is keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...
ised. Consequently, the tongue can grind against the hard palate without being itself damaged or irritated.
Speech
The tongue is one of the primary articulators in 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 vowel
A vowel is a syllabic speech sound pronounced without any stricture in the vocal tract. Vowels are one of the two principal classes of speech sounds, the other being the consonant. Vowels vary in quality, in loudness and also in quantity (leng ...
s are articulated
An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing it to turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were someti ...
by changing the tongue's height and retraction to alter the resonant
Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillatin ...
properties of the vocal tract
The vocal tract is the cavity in human bodies and in animals where the sound produced at the sound source (larynx in mammals; syrinx (biology), syrinx in birds) is filtered.
In birds it consists of the Vertebrate trachea, trachea, the Syrinx (bio ...
. These resonant properties amplify specific harmonic frequencies (formant
In speech science and phonetics, a formant is the broad spectral maximum that results from an acoustic resonance of the human vocal tract. In acoustics, a formant is usually defined as a broad peak, or local maximum, in the spectrum. For harmoni ...
s) that are different for each vowel, while attenuating other harmonics. For example, is produced with the tongue lowered and centered and is produced with the tongue raised and fronted. Consonant
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract. Examples are and pronounced with the lips; and pronounced with the front of the tongue; and pronounced wit ...
s 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 consonant
Alveolar (; UK also ) consonants are articulated with the tongue against or close to the superior alveolar ridge, which is called that because it contains the alveoli (the sockets) of the upper teeth. Alveolar consonants may be articulated with ...
s like and are articulated with the tongue against the alveolar ridge
The alveolar process () or alveolar bone is the thickened ridge of bone that contains the tooth sockets on the jaw bones (in humans, the maxilla and the mandible). The structures are covered by gums as part of the oral cavity.
The synonymous ter ...
, while velar consonants
Velars are consonants articulated with the back part of the tongue (the dorsum) against the soft palate, the back part of the roof of the mouth (known also as the velum).
Since the velar region of the roof of the mouth is relatively extensive an ...
like and are articulated with the tongue dorsum against the soft palate (velum). Tongue shape is also relevant to speech articulation, for example in retroflex consonants
A retroflex ( /ˈɹɛtʃɹoːflɛks/), apico-domal ( /əpɪkoːˈdɔmɪnəl/), or cacuminal () consonant is a coronal consonant where the tongue has a flat, concave, or even curled shape, and is articulated between the alveolar ridge and the har ...
, where the tip of the tongue is curved backward.
Intimacy
The tongue plays a role in physical intimacy
Physical intimacy is sensual proximity or touching. It is an act or reaction, such as an expression of feelings (including close friendship, platonic love, romantic love or sexual attraction), between people. Examples of physical intimacy i ...
and sexuality
Human sexuality is the way people experience and express themselves sexually. This involves biological, psychological, physical, erotic, emotional, social, or spiritual feelings and behaviors. Because it is a broad term, which has varied ...
. The tongue is part of the erogenous zone
An erogenous zone (from Greek , ''érōs'' "love"; and English ''-genous'' "producing", from Greek , ''-genḗs'' "born") is an area of the human body that has heightened sensitivity, the stimulation of which may generate a sexual response, su ...
of the mouth and can be used in intimate contact, as in the French kiss
A French kiss, also known as cataglottism or a tongue kiss, is an amorous kiss in which the participants' tongues extend to touch each other's lips or tongue. A kiss with the tongue stimulates the partner's lips, tongue and mouth, which are sens ...
and in oral sex
Oral sex, sometimes referred to as oral intercourse, is sexual activity involving the stimulation of the genitalia of a person by another person using the mouth (including the lips, tongue, or teeth) and the throat. Cunnilingus is oral sex per ...
. The tongue can be used for stimulating the clitoris
The clitoris ( or ) is a female sex organ present in mammals, ostriches and a limited number of other animals. In humans, the visible portion – the glans – is at the front junction of the labia minora (inner lips), above the ope ...
and other areas of the vulva.
Clinical significance
Disease
A congenital disorder
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...
of the tongue is that of ankyloglossia
Ankyloglossia, also known as tongue-tie, is a congenital oral anomaly that may decrease the mobility of the tongue tip and is caused by an unusually short, thick lingual frenulum, a membrane connecting the underside of the tongue to the floor of ...
also known as ''tongue-tie''. The tongue is ''tied'' to the floor of the mouth by a very short and thickened frenulum
A frenulum (or frenum, plural: frenula or frena, from the Latin ''frēnulum'', "little bridle", the diminutive of ''frēnum'') is a small fold of tissue that secures the motion of a mobile organ in the body.
In human anatomy
Frenula on the h ...
and this affects speech, eating, and swallowing.
The tongue is prone to several pathologies
Pathology is the study of the causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in t ...
including glossitis
Glossitis can mean soreness of the tongue, or more usually inflammation with depapillation of the dorsal surface of the tongue (loss of the lingual papillae), leaving a smooth and erythematous (reddened) surface, (sometimes specifically termed atro ...
and other inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
s such as geographic tongue
Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by a ...
, and median rhomboid glossitis
Median rhomboid glossitis is a condition characterized by an area of redness and loss of lingual papillae on the central dorsum of the tongue, sometimes including lesions of the tongue and palate. It is seen in patients using inhaled steroids a ...
; burning mouth syndrome
Burning mouth syndrome (BMS) is a burning, tingling or scalding sensation in the mouth, lasting for at least four to six months, with no underlying known dental or medical cause. No related signs of disease are found in the mouth. People with ...
, oral hairy leukoplakia
Hairy leukoplakia is a white patch on the side of the tongue with a corrugated or hairy appearance. It is caused by Epstein-Barr virus (EBV) and occurs usually in persons who are immunocompromised, especially those with human immunodeficiency v ...
, oral candidiasis
Oral candidiasis, also known as oral thrush among other names, is candidiasis that occurs in the mouth. That is, oral candidiasis is a mycosis (yeast/fungal infection) of ''Candida'' species on the mucous membranes of the mouth.
''Candida albic ...
(thrush), black hairy tongue
Black hairy tongue syndrome (BHT) is a condition of the tongue in which the filiform papilla, small bumps on the tongue elongate with black or brown discoloration, giving a black and hairy appearance. The appearance may be alarming, but it is ...
, bifid tongue (due to failure in fusion of two lingual swellings of first pharyngeal arch) and fissured tongue
Fissured tongue is a benign condition characterized by deep grooves (fissures) in the dorsum of the tongue. Although these grooves may look unsettling, the condition is usually painless. Some individuals may complain of an associated burning sen ...
.
There are several types of oral cancer
Oral cancer, also known as mouth cancer, is cancer of the lining of the lips, mouth, or upper throat. In the mouth, it most commonly starts as a painless white patch, that thickens, develops red patches, an ulcer, and continues to grow. When on ...
that mainly affect the tongue. Mostly these are squamous cell carcinoma
Squamous-cell carcinomas (SCCs), also known as epidermoid carcinomas, comprise a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on the ...
s.
Food debris, desquamated epithelial cells
Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellula ...
and bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
often form a visible tongue coating. This coating has been identified as a major factor contributing to bad breath
Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder.
Th ...
(halitosis), which can be managed by using a tongue cleaner
A tongue cleaner (also called a tongue scraper or tongue brush) is an oral hygiene device designed to clean the coating on the upper surface of the tongue. While there is tentative benefit from the use of a tongue cleaner it is insufficient to ...
.[ ]
Medication delivery
The sublingual
Sublingual (abbreviated SL), from the Latin for "under the tongue", refers to the pharmacological route of administration by which substances diffuse into the blood through tissues under the tongue.
The sublingual glands receive their prima ...
region underneath the front of the tongue is an ideal location for the administration
Administration may refer to:
Management of organizations
* Management, the act of directing people towards accomplishing a goal
** Administrative assistant, Administrative Assistant, traditionally known as a Secretary, or also known as an admini ...
of certain medications into the body. The oral mucosa
The oral mucosa is the mucous membrane lining the inside of the mouth. It comprises stratified squamous epithelium, termed "oral epithelium", and an underlying connective tissue termed ''lamina propria''. The oral cavity has sometimes been descri ...
is very thin underneath the tongue, and is underlain by a plexus of veins. The sublingual route takes advantage of the highly vascular
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away f ...
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
A route of administration in pharmacology and toxicology is the way by which a medication, drug, fluid, poison, or other substance is taken into the body.
Routes of administration are generally classified by the location at which the substance i ...
(apart from Intravenous therapy
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutri ...
) of nitroglycerin
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating g ...
to a patient suffering chest pain from angina pectoris
Angina, also known as angina pectoris, is chest pain or pressure, usually caused by insufficient blood flow to the heart muscle (myocardium). It is most commonly a symptom of coronary artery disease.
Angina is typically the result of obstru ...
.
Other animals
The muscles of the tongue evolved in amphibians
Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbore ...
from occipital
The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cereb ...
somite
The somites (outdated term: primitive segments) are a set of bilaterally paired blocks of paraxial mesoderm that form in the embryonic stage of somitogenesis, along the head-to-tail axis in segmented animals. In vertebrates, somites subdivide in ...
s. Most amphibians show a proper tongue after their metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...
. As a consequence most vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
animals—amphibians, reptiles, birds, and mammals—have tongues (the frog
A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...
family of pipids lack tongue). In mammals such as dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s and cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...
s, the tongue is often used to clean the fur and body by licking
Licking is the action of passing the tongue over a surface, typically either to deposit saliva onto the surface, or to collect liquid, food or minerals onto the tongue for ingestion, or to communicate with other animals. Many animals both gro ...
. 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
A skin condition, also known as cutaneous condition, is any medical condition that affects the integumentary system—the organ system that encloses the body and includes skin, nails, and related muscle and glands. The major function of this sy ...
known as a lick granuloma
A lick granuloma, also known as acral lick dermatitis, is a skin disorder found most commonly in dogs, but also in cats. In dogs, it results typically from the dog's urge to lick the lower portion of one of their legs.
The lesion can initially be ...
. 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 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, chameleon
Chameleons or chamaeleons (family Chamaeleonidae) are a distinctive and highly specialized clade of Old World lizards with 202 species described as of June 2015. The members of this family are best known for their distinct range of colors, bein ...
s, frog
A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...
s, pangolin
Pangolins, sometimes known as scaly anteaters, are mammals of the order Pholidota (, from Ancient Greek ϕολιδωτός – "clad in scales"). The one extant family, the Manidae, has three genera: '' Manis'', '' Phataginus'', and '' Smut ...
s and anteater
Anteater is a common name for the four extant mammal species of the suborder Vermilingua (meaning "worm tongue") commonly known for eating ants and termites. The individual species have other names in English and other languages. Together with ...
s have prehensility, prehensile tongues.
Other animals may have organs that are analogy (biology), analogous to tongues, such as a butterfly's proboscis or a radula on a mollusca, mollusc, but these are not Homology (biology), homologous with 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 tetrapod
Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids ( pelycosaurs, extinct t ...
s.
Society and culture
Figures of speech
The tongue can be used as a metonymy, 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 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 Recollection, retrieval from memory is referred to as the ''Tip of the tongue, tip-of-the-tongue'' phenomenon. The expression ''Tongue-in-cheek, tongue in cheek'' refers to 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 made specifically to be very difficult to pronounce. Aside from being a Ankyloglossia, 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" 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 is no true spoken language itself. A deceptive person is said to have a forked tongue, and a smooth-talking person said to have a .
Gestures
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, a farmer from Fabriano, Italy, was convicted and fined by Court of Cassation (Italy), the country'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.
Body art
Tongue piercing and tongue splitting, splitting have become more common in western countries in recent decades. In one study, one-fifth of young adults were found to have at least one type of oral piercing, most commonly the tongue.
As food
The tongues of some animals are consumed and sometimes considered delicacies. Hot tongue sandwiches are frequently found on menus in kashrut, kosher delicatessens in America. Taco, Taco de lengua (''lengua'' being Spanish for tongue) is a taco filled with beef tongue, and is especially popular in Mexican cuisine. As part of Colombian gastronomy, Tongue in Sauce (Lengua en Salsa), is a dish prepared by frying the tongue, adding tomato sauce, onions and salt. Tongue can also be prepared as birria. Pig and beef tongue are consumed in Chinese cuisine. Duck tongues are sometimes employed in Szechuan cuisine, Szechuan dishes, while Lamb (food), lamb's tongue is occasionally employed in Continental and contemporary American cooking. Fried cod "tongue" is a relatively common part of fish meals in Norway and Newfoundland and Labrador, Newfoundland. In Argentina and Uruguay cow tongue is cooked and served in vinegar (''lengua a la vinagreta''). In the Czech Republic and Poland, a pork tongue is considered a delicacy, and there are many ways of preparing it. In Eastern Slavic countries, pork and beef tongues are commonly consumed, boiled and garnished with horseradish or jelled; beef tongues fetch a significantly higher price and are considered more of a delicacy. In Alaska, cow tongues are among the more common. Both cow and moose tongues are popular toppings on open-top-sandwiches in Norway, the latter usually amongst hunters.
Tongues of seals and whales have been eaten, sometimes in large quantities, by sealers and whalers, and in various times and places have been sold for food on shore.
Additional images
File:Tongue.agr.jpg, The human tongue
File:Spots on the tongue.jpg, Spots on the tongue
File:زبان.jpg, Exclusive Lines on the tongue
File:Okapitongue.jpg, An okapi cleaning its snout, muzzle with its tongue.
File:Gähnende, liegende graue Katze.jpg, A yawning cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...
's tongue is comb-like.
File:Mouth illustration-Otis Archives.jpg, Medical illustration of a human mouth by Duncan Kenneth Winter
File:Dog tongue.png, Distended dog tongue acting as a heat regulator
See also
* Electronic tongue
* Tongue map
The tongue map or taste map is a common misconception that different sections of the tongue are exclusively responsible for different basic tastes. It is illustrated with a schematic map of the tongue, with certain parts of the tongue labeled for ...
* Vocal tract
References
External links
University of Manitoba, Anatomy of the Vocal Tract
{{Portal bar, Anatomy
Tongue,
Sensory organs
Gustatory system
Digestive system
Human mouth anatomy
Speech organs