The lingual tonsils are a collection of
lymphatic tissue
The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system, and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphatic or lymphoid o ...
located in the lamina propria of the root of the
tongue
The tongue is a muscular organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive process, and is the primary organ of taste. The tongue's upper surface (dorsum) is covered by taste b ...
.
This lymphatic tissue consists of the lymphatic nodules rich in cells of the
immune system (
immunocyte
White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from multi ...
s).
The immunocytes initiate the immune response when the lingual tonsils get in contact with invading
microorganisms (
pathogenic bacteria,
viruses or
parasites
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has c ...
).
Structure
Microanatomy
Lingual tonsils are covered externally by stratified squamous nonkeratinized epithelium that invaginates inward forming crypts. Beneath the epithelium is a layer of lymphoid nodules containing lymphocytes.
Mucous glands located at the root of tongue are drained through several ducts into the crypt of lingual tonsils.
Secretions of these mucous glands keep the crypt clean and free of any debris.
Blood supply
Lingual tonsils are located on posterior aspect of tongue which is supplied through:
* Lingual artery, branch of external carotid artery
* Tonsillar branch of facial artery
*Ascending and descending palatine arteries
* Ascending pharyngeal branch of external carotid artery
Nerve supply
Lingual tonsils are innervated by tonsillar nerves from the tonsilar plexus, formed by the glossopharyngeal and vagus nerves.
Function
Like other lymphatic tissues, the function of lingual tonsils is to prevent infections. These tonsils contain B and T lymphocytes which get activated when harmful bacteria and viruses come in contact with tonsils. B lymphocytes kill pathogens by producing antibodies against them, while T lymphocytes directly kill them by engulfing them or indirectly by stimulating other cells of the immune system.
Clinical significance
Cancer
Squamous cell
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 ...
carcinoma is a type of neoplasm that can affect lingual tonsils.
Sleep apnea
Enlarged or hypertrophic lingual tonsils have the potential to cause or exacerbate sleep apnea.
Additional images
File:Slide1sss.JPG, Lingual tonsil
File:Slide7ttt.JPG, Lingual tonsil
File:Slide12uuu.JPG, Lingual tonsils
External links
Pictures at usc.edu*
*
* (labeled as 'lymphoid tissue')]
Lingual Tonsil
References
{{Authority control
Lymphatics of the head and neck
Tongue
Tonsil