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| Image = Illu01 head neck.jpg
| Caption = Head and inner neck
| Width =
| Image2 = Illu_pharynx.jpg
| Caption2 = Pharynx
| Precursor =
| System =
| Artery = [[
| Vein = [[
| Nerve = [[
| Lymph =
| part_of = [[Throat]]
| system = [[Respiratory system]], [[digestive system]]
}}
The '''pharynx''' ({{plural form}}: '''pharynges''') is the part of the [[throat]] behind the [[human mouth|mouth]] and [[nasal cavity]], and above the [[
In humans, the pharynx is part of the [[Digestion|digestive system]] and the [[conducting zone]] of the [[respiratory system]]. (The conducting zone—which also includes the [[nostril]]s of the [[Human nose|nose]], the [[larynx]], [[trachea]], [[bronchus|bronchi]], and [[bronchiole]]s—filters, warms and moistens air and conducts it into the [[lung]]s).<ref>{{Cite book | vauthors = Fasick J |title = Respiratory Syster|publisher = Benjamin Cummings (Pearson Education, Inc)|year = 2006|pages = 1|url = http://www.kean.edu/~jfasick/docs/Spring%20Semester%20Lectures%20Chapt.%2016-28/Chapter%2022a.pdf | archive-url = https://web.archive.org/web/20140612010803/http://www.kean.edu/~jfasick/docs/Spring%20Semester%20Lectures%20Chapt.%2016-28/Chapter%2022a.pdf | archive-date = 12 June 2014 }}</ref> The human pharynx is conventionally divided into three sections: the '''nasopharynx''', '''oropharynx''', and '''laryngopharynx
In humans, two sets of [[pharyngeal muscles]] form the pharynx and determine the shape of its [[lumen (anatomy)|lumen]]. They are arranged as an inner layer of longitudinal muscles and an outer circular layer.
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== Structure ==
===Nasopharynx===
[[File:
The upper portion of the pharynx, the nasopharynx, extends from the base of the [[skull]] to the upper surface of the [[soft palate]].<ref>Clinical Head and Neck and Functional Neuroscience Course Notes, 2008-2009, [[Uniformed Services University of the Health Sciences]] School of Medicine, Bethesda, Maryland</ref> It includes the space between the [[choana|internal nares]] and the soft palate and lies above the oral cavity. The [[adenoids]], also known as the pharyngeal tonsils, are [[lymphoid tissue]] structures located in the posterior wall of the nasopharynx. [[Waldeyer's tonsillar ring]] is an annular arrangement of lymphoid tissue in both the nasopharynx and oropharynx. The nasopharynx is lined by [[respiratory epithelium]] that is pseudostratified, columnar, and ciliated.
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The anterior aspect of the nasopharynx communicates through the [[choanae]] with the nasal cavities. On its lateral wall is the [[Eustachian tube#Structure|pharyngeal opening of the auditory tube]], somewhat triangular in shape and bounded behind by a firm prominence, the [[torus tubarius]] or cushion, caused by the medial end of the cartilage of the tube that elevates the [[mucous membrane]].
Two folds arise from the cartilaginous opening:
* the '''salpingopharyngeal fold''', a vertical fold of mucous membrane extending from the inferior part of the torus and containing the [[salpingopharyngeus muscle]].
* the '''salpingopalatine fold''', a smaller fold, in front of the salpingopharyngeal fold, extending from the superior part of the torus to the palate and containing the
===Oropharynx===
The oropharynx lies behind the oral cavity, extending from the [[uvula]] to the level of the [[hyoid bone]]. It opens anteriorly, through the [[isthmus faucium]], into the mouth, while in its lateral wall, between the [[palatoglossal arch]] and the [[palatopharyngeal arch]], is the [[palatine tonsil]].<ref>{{cite web|url=http://teachmeanatomy.info/neck/viscera/pharynx/|title=The Pharynx | work = TeachMeAnatomy |date=28 July 2013}}</ref> The anterior wall consists of the base of the tongue and the [[epiglottic vallecula]]; the lateral wall is made up of the tonsil, tonsillar fossa, and tonsillar (faucial) pillars; the superior wall consists of the inferior surface of the soft palate and the uvula. Because both food and air pass through the pharynx, a flap of connective tissue called the [[epiglottis]] closes over the [[glottis]] when food is swallowed to prevent [[Pulmonary aspiration|aspiration]]. The oropharynx is lined by non-keratinized squamous stratified epithelium.
The ''HACEK'' organisms (''[[Haemophilus|'''H'''aemophilus]], [[Actinobacillus|'''A'''ctinobacillus actinomycetemcomitans]], [[Cardiobacterium hominis|'''C'''ardiobacterium hominis]], [[Eikenella|'''E'''ikenella corrodens]], [[Kingella|'''K'''ingella]]'') are part of the normal oropharyngeal flora, which grow slowly, prefer a carbon dioxide-enriched atmosphere, and share an enhanced capacity to produce [[endocardial]] infections, especially in young children.<ref name="pmid18087053">{{cite journal | vauthors = Morpeth S, Murdoch D, Cabell CH, Karchmer AW, Pappas P, Levine D, Nacinovich F, Tattevin P, Fernández-Hidalgo N, Dickerman S, Bouza E, del Río A, Lejko-Zupanc T, de Oliveira Ramos A, Iarussi D, Klein J, Chirouze C, Bedimo R, Corey GR, Fowler VG | display-authors = 6 | title = Non-HACEK gram-negative bacillus endocarditis | journal = Annals of Internal Medicine | volume = 147 | issue = 12 | pages = 829–835 | date = December 2007 | pmid = 18087053 | doi = 10.7326/0003-4819-147-12-200712180-00002 | s2cid = 11122488 }}</ref> ''[[Fusobacterium]]'' is a pathogen.<ref name="ludlam2004">{{cite journal | vauthors = Aliyu SH, Marriott RK, Curran MD, Parmar S, Bentley N, Brown NM, Brazier JS, Ludlam H | display-authors = 6 | title = Real-time PCR investigation into the importance of Fusobacterium necrophorum as a cause of acute pharyngitis in general practice | journal = Journal of Medical Microbiology | volume = 53 | issue = Pt 10 | pages = 1029–1035 | date = October 2004 | pmid = 15358827 | doi = 10.1099/jmm.0.45648-0 | doi-access = free }}</ref>
===Laryngopharynx===
The laryngopharynx, ([[Latin]]: ''pars laryngea pharyngis''), also known as '''hypopharynx''', is the [[Caudal (anatomical term)|caudal]] part of the pharynx; it is the part of the throat that connects to the esophagus. It lies inferior to the epiglottis and extends to the location where this common pathway diverges into the respiratory ([[larynx|laryngeal]]) and digestive ([[Esophagus|esophageal]]) pathways. At that point, the laryngopharynx is continuous with the esophagus posteriorly. The esophagus conducts food and fluids to the stomach; air enters the larynx anteriorly. During swallowing, food has the "right of way", and air passage temporarily stops. Corresponding roughly to the area located between the 4th and 6th [[cervical vertebrae]], the superior boundary of the laryngopharynx is at the level of the [[hyoid bone]]. The laryngopharynx includes three major sites: the [[pyriform sinus]], postcricoid area, and the posterior pharyngeal wall. Like the oropharynx above it, the laryngopharynx serves as a passageway for food and air and is lined with a [[stratified squamous epithelium]]. It is innervated by the [[pharyngeal plexus of vagus nerve|pharyngeal plexus]] and by the [[recurrent laryngeal nerve]].
The vascular supply to the laryngopharynx includes the [[superior thyroid artery]], the [[lingual artery]] and the [[ascending pharyngeal artery]]. The primary neural supply is from both the [[vagus nerve|vagus]] and [[glossopharyngeal nerves|glossopharyngeal]] nerves. The vagus nerve provides an [[auricular branch of vagus nerve|auricular branch]] also termed "Arnold's nerve" which also supplies the external auditory canal, thus laryngopharyngeal cancer can result in referred [[ear pain]]. This nerve is also responsible for the [[Cough reflex#Physiology of cough|ear-cough reflex]] in which stimulation of the ear canal results in a person coughing.
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=== Waldeyer's tonsillar ring ===
{{Main|Waldeyer's tonsillar ring}}
[[Waldeyer's tonsillar ring]] is an anatomical term collectively describing the annular arrangement of lymphoid tissue in the pharynx. Waldeyer's ring circumscribes the naso- and oropharynx, with some of its tonsillar tissue located above and some below the soft palate (and to the back of the oral cavity). It is believed that Waldeyer's ring prevents the invasion of microorganisms from going into the air and food passages and this helps in the defense mechanism of the respiratory and alimentary systems.<ref>{{Cite
==Etymology==
The word ''pharynx'' ({{IPAc-en|ˈ|f|ær|ɪ|ŋ|k|s}}<ref>''[[OED]]'' 2nd edition, 1989.</ref><ref>[http://www.merriam-webster.com/dictionary/pharynx Entry "pharynx"] in ''[http://www.merriam-webster.com/ Merriam-Webster Online Dictionary]'', retrieved 2012-07-28.</ref>) is derived from the [[Ancient Greek|Greek]] φάρυγξ ''phárynx'', meaning "throat". Its plural form is ''pharynges'' {{IPAc-en|f|ə|ˈ|r|ɪ|n|dʒ|i:|z}} or ''pharynxes'' {{IPAc-en|ˈ|f|ær|ɪ|ŋ|k|s|ə|z}}, and its adjective form is ''
==Other vertebrates==
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===Pharyngeal arches===
Pharyngeal arches are characteristic features of vertebrates whose origin can be traced back through [[chordates]] to basal [[deuterostomes]] who also share endodermal outpocketings of the pharyngeal apparatus. Similar patterns of gene expression can be detected in the developing pharynx of [[Lancelet|amphioxi]] and [[hemichordate]]s. However, the vertebrate pharynx is unique in that it gives rise to [[endoskeletal]] support through the contribution of [[neural crest]] cells.<ref name="pmid23020903">{{cite journal | vauthors = Graham A, Richardson J | title = Developmental and evolutionary origins of the pharyngeal apparatus | journal = EvoDevo | volume = 3 | issue = 1 | pages = 24 | date = October 2012 | pmid = 23020903 | pmc = 3564725 | doi = 10.1186/2041-9139-3-24 | doi-access = free }}</ref>
===Pharyngeal jaws {{anchor|Pharyngeal_jaws}}===
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==Invertebrates==
[[Invertebrate]]s also have a pharynx. Invertebrates with a pharynx include the [[tardigrade]]s,<ref>{{cite journal |doi=10.1046/j.1439-0469.2001.00140.x |title=Are the supportive structures of the tardigrade pharynx homologous throughout the entire group? |journal=Journal of Zoological Systematics and Evolutionary Research |volume=39 |issue=1–2 |page=1 |date=March–June 2001 | vauthors = Eibye-Jacobsen J |doi-access=free }}</ref> [[annelid]]s and [[arthropod]]s,<ref>{{cite journal |title=Microspines in the alimentary canal of arthropoda, onychophora, annelida |journal=International Journal of Insect Morphology and Embryology |volume=27 |issue=4 |page=341 |date=October 1998 | vauthors = Elzinga RJ |doi=10.1016/S0020-7322(98)00027-0}}</ref> and the [[priapulida|priapulids]] (which have an eversible pharynx).<ref>{{cite journal | vauthors = Morse MP |date=July 1981 |title=''Meiopriapulus fijiensis'' n. gen., n. sp.: An Interstitial Priapulid from coarse sand in Fiji |journal=Transactions of the American Microscopical Society |volume =100 |issue=3 |pages=239–252 |jstor=3225549 |doi=10.2307/3225549}}</ref>
The "pharynx" of the [[nematode]] worm is a muscular food pump in the head, triangular in cross-section, that grinds food and transports it directly to the intestines. A one-way valve connects the pharynx to the excretory canal.
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<gallery>
File:Alitta virens pharynx (lateral).jpg|Everted pharynx of ''[[Alitta virens]]'' (also known as ''Nereis virens''), lateral view
File:Prorhynchus fontinalis pharynx.jpg| Pharynx of the [[flatworm]] ''[[Prorhynchus fontinalis]]''
File:Peerj-297-fig-5 Platydemus manokwari.png|Pharynx of the [[flatworm]] ''[[Platydemus manokwari]]'' visible as the worm feeds on a snail.
File:C elegans anatomy.png|Longitudinal section through the roundworm ''[[Caenorhabditis elegans]]'' showing the position of the pharynx in the animal body.
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{{Anatomy-terms}}
{{col div|colwidth=30em}}
* [[Cricopharyngeal ligament]]
* [[Nasopharyngeal carcinoma]]
*[[Pharyngeal aspiration]]▼
* [[Pharyngeal
* [[Pharyngeal
* ''[[Saccopharynx]]'', a genus of deep-sea eel-like fishes with large mouths, distensible stomachs and long scaleless bodies
* [[
* [[
* [[Tornwaldt cyst]]
{{colend}}
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[[Category:Human voice]]
[[Category:Animal anatomy]]
[[Category:Otorhinolaryngology]]
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