General information
The tongue (lingua) is an elongated muscle covered by mucous membrane, which is located inside the oral cavity, which it fills almost completely when the mouth is closed. The tongue is already part of the upper digestive tract and performs important functions in digestion.
- Chewing and
- Swallow and is also involved in the processes of
- Taste and
- Keys (which makes it also a sensory organ).
Division of the tongue
With the tongue, macroscopically different sections can be distinguished. The root of the tongue is located at the very back (also: base of the tongue, radix linguae). This is the thickest part of the tongue, which contains not only muscle tissue, but also the lingual tonsil (Tonsilla linguae), which consists of lymphatic tissue and is part of the defense system.
The root of the tongue is firmly anchored to the hyoid bone (Os hyoideum), which in turn is attached to the larynx by ligaments and muscles. This connection is extremely important for the swallowing process. The root of the tongue is followed by the body of the tongue (Corpus linguae).
The transition between the two areas is marked by the so-called sulcus terminalis, a notch on the surface of the tongue. The body of the tongue consists of several layers of striated muscles, which can be divided into an inner and an outer group. The muscle fibers run from front to back, from top to bottom and from right to left, creating a network that allows our tongue to move flexibly in any direction and to take on different shapes (for example, to appear thicker or thinner).
Apart from the muscle tissue, the body of the tongue also contains nerves and blood vessels that run between the individual muscle fiber bundles. The septum linguae, a kind of septum consisting of tendon fibres, runs across the middle of the body of the tongue from front to back. At the very front is the tip of the tongue (apex linguae), where the two outer edges of the tongue meet.
The upper outer surface of the tongue is called the dorsum linguae, which has a slight upward curvature and is completely exposed. In the back part of the back of the tongue a triangular depression can be seen, which is also called blind hole (Foramen caecum). This hole is a remnant of a duct that once connected the oral cavity with the thyroid gland (Ductus thyreoglossus), but is now closed.
Several mucous glands now open out here. The underside of the tongue (Facies inferior linguae) is not completely exposed. Its middle part is firmly attached to the oral cavity.
In the front there is a fold in the mucous membrane of the mouth, the so-called frenulum of the tongue (Frenulum linguae), over which the tongue is attached in such a way that its lateral edges and the tip are exposed. There is a developmental disorder in which the frenulum of tongue extends too far forward (ankyloglosson). Infants affected by this disorder are noticed by the fact that they have difficulty sucking (and therefore often do not eat enough) and are restricted in their ability to produce sounds.
However, this disorder can be remedied relatively easily by cutting the frenulum of tongue. The vascular supply to the tongue is provided by an artery called the lingual artery, which branches off from the external carotid artery and is only responsible for supplying the tongue. It branches out into several smaller branches, including the sublingual artery and the profunda linguae artery. The blood can finally drain off again via the lingual vein.
