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"Gullet" redirects here. For the African sailboat, see Gulet. For the Dutch football player and manager, see Ruud Gullit. For the parts of a saw, see Saw#Terminology.
"Weasand" redirects here. For other meanings, see Weasand (disambiguation).
It has been suggested that Upper_esophageal_sphincter be merged into this article. (Discuss) Proposed since October 2013.
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The esophagus relations to pharynx and mouth
Digestive organs (esophagus is #1)
subject #245 1144
Part of the digestive System
Celiac ganglia, vagus
The esophagus (oesophagus, commonly known as the gullet) is an organ in vertebrates which consists of a muscular tube through which food passes from the pharynx to the stomach. The word esophagus is derived from the Latin œsophagus, which derives from the Greek word oisophagos, lit. "entrance for eating."
In animals, food is ingested through the mouth. During swallowing, food passes from the mouth through the pharynx into the esophagus. The epiglottis folds down to a more horizontal position so as to prevent food from going into the trachea, instead directing it to the esophagus. Once in the esophagus, the bolus travels down to the stomach via rhythmic contraction and relaxation of muscles known as peristalsis.
In humans the esophagus is continuous with the laryngeal part of the pharynx at the level of the C6 vertebra. The esophagus passes through posterior mediastinum in the thorax and enters abdomen through a hole in the diaphragm at the level of the tenth thoracic vertebrae (T10). It is usually about 25cm, but extreme variations have been recorded ranging 10–50 cm long depending on individual height. It is divided into cervical, thoracic and abdominal parts. Due to the inferior pharyngeal constrictor muscle, the entry to the esophagus opens only when swallowing or vomiting.
5In other animals
Course of the esophagus (anterior view), showing it passing posteriorly to the trachea and the heart.
The layers of the oesophagus are as follows:
nonkeratinized stratified squamous epithelium: is rapidly turned over, and serves a protective effect due to the high volume transit of food, saliva and mucus.
lamina propria: sparse.
muscularis mucosae: smooth muscle
submucosa: Contains the mucous secreting glands (esophageal glands), and connective structures termed papillae.
muscularis externa (or "muscularis propria"): composition varies in different parts of the esophagus, to correspond with the conscious control over swallowing in the upper portions and the autonomic control in the lower portions:
upper third, or superior part: striated muscle
middle third, smooth muscle and striated muscle
inferior third: predominantly smooth muscles
Similar to rectum, it lacks serosa
Normally, the esophagus has three anatomic constrictions at the following levels:
At the esophageal inlet, where the pharynx joins the esophagus, behind the cricoid cartilage (14–16 cm from the incisor teeth).
Where its anterior surface is crossed by the aortic arch and the left bronchus (25–27 cm from the incisor teeth).
Where it pierces the diaphragm (36–38 cm from the incisor teeth).
The distances from the incisor teeth are important as is useful for diagnostic endoscopic procedures.
At rest, the esophagus is closed at both ends by the upper esophageal sphincter (UES) at the top, and the lower esophageal sphincter (LES) at the bottom.
The junction between the esophagus and the stomach (the gastroesophageal junction or GE junction) is controlled by the lower esophageal sphincter (LES), which remains constricted at all times other than during swallowing and vomiting to prevent the contents of the stomach from entering the esophagus. As the esophagus does not have the same protection from acid as the stomach, any failure of the LES can lead to heartburn.
In the esophagus, as in much of the gastrointestinal tract, smooth muscles contract in sequence to produce a peristaltic wave which forces a ball of food (called a bolus) down and through the LES into the stomach.
In other animals
In most fish, the esophagus is extremely short, primarily due to the length of the pharynx (which is associated with the gills). However, some fish, including lampreys, chimaeras, and lungfish, have no true stomach, so that the esophagus effectively runs from the pharynx directly to the intestine, and is therefore somewhat longer.
In tetrapods, the pharynx is much shorter, and the esophagus correspondingly longer, than in fish. In amphibians, sharks and rays, the esophageal epithelium is ciliated, helping to wash food along, in addition to the action of muscular peristalsis. In the majority of vertebrates, the esophagus is simply a connecting tube, but in birds, it is extended towards the lower end to form a crop for storing food before it enters the true stomach.
A structure with the same name is often found in invertebrates, including molluscs and arthropods, connecting the oral cavity with the stomach.
H&E stain of biopsy of normal esophagus showing the stratified squamous cell epithelium
Layers of the esophagus.
Accessory digestive system.
Organs of the digestive tract.
Section of the neck at about the level of the sixth cervical vertebra.
Transverse section of thorax, showing relations of pulmonary artery.
Sagittal section of nose mouth, pharynx, and larynx.
The position and relation of the esophagus in the cervical region and in the posterior mediastinum. Seen from behind. |
Section of the human esophagus. Moderately magnified.
Microscopic shot of a cross section of human gastroesophageal junction wall.
Micrograph of herpes esophagitis. H&E stain.
Ultrasound image of the fetal esophagus at 19 weeks of pregnancy.
^Physiology at MCG 6/6ch2/s6ch2_30
^BU Histology Learning System: 10801loa
^ abRomer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 344–345. ISBN 0-03-910284-X.
Look up esophagus in resource, the free dictionary.
Virtual Slidebox at Univ. Iowa Slide 449
Esophagus Foreign Body MedPix Radiology Teaching File
Human systems and organs
TA 2–4: MS
Collar bone (clavicle)
Thigh bone (femur)
TA 5–11: splanchnic/ viscus
GU: Urinary system
GU: Reproductive system
Islets of Langerhans
Myeloid immune system
Lymphoid immune system
General anatomy: systems and organs, regional anatomy, planes and lines, superficial axial anatomy, superficial anatomy of limbs
Anatomy of torso, digestive system: Gastrointestinal tract, excluding mouth (TA A05.3–7, TH H3.04.02-04, GA 11.1141)
Serosa / Adventitia
Major duodenal papilla
Minor duodenal papilla
Transverse folds of rectum
Sphincter ani internus muscle
Sphincter ani externus muscle
anat (t, g, p)/phys/devp/enzy
proc, drug (A2A/2B/3/4/5/6/7/14/16), blte
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