Food is ingested through the mouth and when swallowed passes first into the pharynx and then into the esophagus. The esophagus is thus one of the first components of the digestive system and the gastrointestinal tract. After food passes through the esophagus, it enters the stomach. When food is being swallowed, the epiglottis moves backward to cover the larynx, preventing food from entering the trachea. At the same time, the upper esophageal sphincter relaxes, allowing a bolus of food to enter. Peristaltic contractions of the esophageal muscle push the food down the esophagus. These rhythmic contractions occur both as a reflex response to food that is in the mouth, and also as a response to the sensation of food within the esophagus itself.
Swallowing
Esophagus
Esophagus | Swallowing
Peristaltic contractions. Sorry. I cannot find the answer based on the context. Peristaltic contractions Sorry. I cannot find the answer based on the context.
the movement of food in food pipe is called
user
The esophagus, (American English) or oesophagus (British English; see spelling differences) (), informally known as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, which travels behind the trachea and heart, passes through the diaphragm and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word "oesophagus" is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, “I carry”) + ἔφαγον (éphagon, “I ate”).
Esophagus | Introduction
Food is ingested through the mouth and when swallowed passes first into the pharynx and then into the esophagus. The esophagus is thus one of the first components of the digestive system and the gastrointestinal tract. After food passes through the esophagus, it enters the stomach. When food is being swallowed, the epiglottis moves backward to cover the larynx, preventing food from entering the trachea. At the same time, the upper esophageal sphincter relaxes, allowing a bolus of food to enter. Peristaltic contractions of the esophageal muscle push the food down the esophagus. These rhythmic contractions occur both as a reflex response to food that is in the mouth, and also as a response to the sensation of food within the esophagus itself.
Esophagus | Swallowing
The opening of the upper sphincter is triggered by the swallowing reflex so that food is allowed through. The sphincter also serves to prevent back flow from the esophagus into the pharynx. The esophagus has a mucous membrane and the epithelium which has a protective function is continuously replaced due to the volume of food that passes inside the esophagus. During swallowing, food passes from the mouth through the pharynx into the esophagus. The epiglottis folds down to a more horizontal position to direct the food into the esophagus, and away from the trachea. Once in the esophagus, the bolus travels down to the stomach via rhythmic contraction and relaxation of muscles known as peristalsis.
Human digestive system | Esophagus
After food is chewed into a bolus, it is swallowed and moved through the esophagus. Smooth muscles contract behind the bolus to prevent it from being squeezed back into the mouth. Then rhythmic, unidirectional waves of contractions work to rapidly force the food into the stomach. The migrating motor complex (MMC) helps trigger peristaltic waves. This process works in one direction only and its sole esophageal function is to move food from the mouth into the stomach (the MMC also functions to clear out remaining food in the stomach to the small bowel, and remaining particles in the small bowel into the colon).
Peristalsis | Esophagus
Presents as a sensation of food getting stuck (dysphagia) in the mid- or lower esophagus, atypical chest pain, or cough. People often state they must drink liquids to swallow solid food. This motility problem results from atrophy of the gastrointestinal tract wall smooth muscle. This change may occur with or without pathologic evidence of significant tissue fibrosis.
CREST syndrome | Esophageal dysmotility
12) Esophageal peristalsis Like the pharyngeal phase of swallowing, the esophageal phase of swallowing is under involuntary neuromuscular control. However, propagation of the food bolus is significantly slower than in the pharynx. The bolus enters the esophagus and is propelled downwards first by striated muscle (recurrent laryngeal, X) then by the smooth muscle (X) at a rate of 3–5 cm/s. The upper esophageal sphincter relaxes to let food pass, after which various striated constrictor muscles of the pharynx as well as peristalsis and relaxation of the lower esophageal sphincter sequentially push the bolus of food through the esophagus into the stomach.
Swallowing | Esophageal phase
During swallowing, the epiglottis bends backwards, folding over the entrance to the trachea, and preventing food from going into it. The folding backwards is a complex movement the causes of which are not completely understood. It is likely that during swallowing the hyoid bone and the larynx move upwards and forwards, which increases passive pressure from the back of the tongue; because the aryepiglottic muscles contract; because of the passive weight of the food pushing down; and because of contraction of laryngeal and because of contraction of thyroarytenoid muscles. The consequence of this is that during swallowing the bent epiglottis blocks off the trachea, preventing food from going into it; food instead travels down the esophagus, which is behind it.
Epiglottis | Swallowing
Swallowing, sometimes called deglutition in scientific contexts, is the process in the human or animal body that allows for a substance to pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. Swallowing is an important part of eating and drinking. If the process fails and the material (such as food, drink, r medicine) goes through the trachea, then choking or pulmonary aspiration can occur. In the human body the automatic temporary closing of the epiglottis is controlled by the swallowing reflex. The portion of food, drink, or other material that will move through the neck in one swallow is called a bolus.
Swallowing | Introduction
During swallowing, the backward motion of the tongue forces the epiglottis over the glottis' opening to prevent any food that is being swallowed from entering the larynx which leads to the lungs; the larynx is also pulled upwards to assist this process. Stimulation of the larynx by ingested matter produces a strong cough reflex in order to protect the lungs.
Human digestive system | Epiglottis
Along with peristalsis, the lower esophageal sphincter relaxes.
Esophagus | Swallowing
Swallowing consists of two distinct but interrelated processes: 1. Moving food and liquids from the mouth into the stomach through a set of coordinated muscle movements of the mouth larynx, pharynx and the esophagus 2. Protecting the airway to prevent food and liquids from entering the lungs. This natural process of swallowing can be disrupted in many ways. The problem can occur when the movements involved in swallowing are restricted due to a tumor, any type of blockage, or paralysis after a stroke. Besides the motor problems, swallowing can be impaired due to sensory dysfunction, meaning when sensation (the ability to feel) is lost or reduced anywhere in the throat area.
Flexible Endoscopic Evaluation of Swallowing with Sensory Testing | Introduction
The esophagus, commonly known as the foodpipe or gullet, consists of a muscular tube through which food passes from the pharynx to the stomach. The esophagus is continuous with the laryngopharynx. It passes through the posterior mediastinum in the thorax and enters the stomach through a hole in the thoracic diaphragm—the esophageal hiatus, at the level of the tenth thoracic vertebra (T10). Its length averages 25 cm, varying with an individual's height. It is divided into cervical, thoracic and abdominal parts. The pharynx joins the esophagus at the esophageal inlet which is behind the cricoid cartilage. At rest the esophagus is closed at both ends, by the upper and lower esophageal sphincters.
Human digestive system | Esophagus
Several disorders affect the motility of food as it travels down the esophagus. This can cause difficult swallowing, called dysphagia, or painful swallowing, called odynophagia. Achalasia refers to a failure of the lower esophageal sphincter to relax properly, and generally develops later in life. This leads to progressive enlargement of the esophagus, and possibly eventual megaesophagus. A nutcracker esophagus refers to swallowing that can be extremely painful. Diffuse esophageal spasm is a spasm of the esophagus that can be one cause of chest pain. Such referred pain to the wall of the upper chest is quite common in esophageal conditions.
Esophagus | Motility disorders
In many birds, the esophagus is largely a mere gravity chute, and in such events as a seagull swallowing a fish or a stork swallowing a frog, swallowing consists largely of the bird lifting its head with its beak pointing up and guiding the prey with tongue and jaws so that the prey slides inside and down. In fish, the tongue is largely bony and much less mobile and getting the food to the back of the pharynx is helped by pumping water in its mouth and out of its gills. In snakes, the work of swallowing is done by raking with the lower jaw until the prey is far enough back to be helped down by body undulations.
Swallowing | In non-mammal animals
13) Relaxation phase
Swallowing | Esophageal phase
Since the windpipe (trachea) is located so close to the food-pipe (esophagus) this is a critical reflex to be functioning well at all times. Stimulation of this reflex not only results in protection of the airway, it also initiates a swallow. When a swallow is initiated the larynx rises up to two inches, going further away from the esophagus, thereby acting as an additional cover for the airway. During the air pulse administration part of the test it is determined if the reflex (LAR) that initiates the swallow is being responsive enough. The responsiveness depends on the ability of the vagus nerve to feel so that it can properly send the impulse to the brain to initiate the LAR.
Flexible Endoscopic Evaluation of Swallowing with Sensory Testing | Technique
There are contractions along the lower esophagus when this condition happens. These contractions prevent the passage of food.
Esophageal motility disorder | Symptoms
The epiglottis is a leaf-shaped flap in the throat that prevents food from entering the windpipe and the lungs. It stands open during breathing, allowing air into the larynx. During swallowing, it closes to prevent aspiration of food into the lungs, forcing the swallowed liquids or food to go along the esophagus toward the stomach instead. It is thus the valve that diverts passage to either the trachea or the esophagus. The epiglottis is made of elastic cartilage covered with a mucous membrane, attached to the entrance of the larynx. It projects upwards and backwards behind the tongue and the hyoid bone.
Epiglottis | Introduction
In the esophagus, two types of peristalsis occur: During vomiting, the propulsion of food up the esophagus and out the mouth comes from contraction of the abdominal muscles; peristalsis does not reverse in the esophagus.
Peristalsis | Esophagus
He speculated that the muscular nature of the esophagus enabled it to act as a pipe, moving food between the mouth and the stomach. In examining teeth, Schwann was the first to notice "cylindrical cells" connected to both the inner surface of the enamel and the pulp. He also identified fibrils in the dentinal tubes, which later became known as "Tomes's fibers". He speculated on the possible structural and functional significance of the tubes and fibrils.
Theodor Schwann | Specialized cells
Upper gastrointestinal series and their fluoroscopic counterparts use x-rays to image the swallowing motions.
Esophageal motility study | Other diagnostic tests for swallowing
These muscles raise the back of the tongue and also close both sides of the fauces to enable food to be swallowed. Mucus helps in the mastication of food in its ability to soften and collect the food in the formation of the bolus.
Human digestive system | Mouth
Patients usually complain of dysphagia (the feeling of food getting stuck "several seconds" after swallowing), and will point to the suprasternal notch or behind the sternum as the site of obstruction.
Esophageal dysphagia | Signs and symptoms
If there is any injury or swelling of the vagus nerve, the sensation will be diminished. As a result, the reflex responsible for protecting the airway will be affected. During sensory testing it has been shown that a much stronger stimulus is necessary to elicit the LAR if there is any desensitization to the vagus nerve. The second part of the FEESST test involves giving food to the patient and tracking where the food travels in the throat region. Green food coloring is typically given in the food to track the food as it travels along the natural pink-colored tissues of the throat.
Flexible Endoscopic Evaluation of Swallowing with Sensory Testing | Technique
An esophageal food bolus obstruction is a medical emergency caused by the obstruction of the esophagus by an ingested foreign body. It is usually associated with diseases that may narrow the lumen of the esophagus, such as eosinophilic esophagitis, Schatzki rings, peptic strictures, webs, or cancers of the esophagus; rarely it can be seen in disorders of the movement of the esophagus, such as nutcracker esophagus. While some esophageal food boli can pass by themselves or with the assistance of medications, some require the use of endoscopy to push the obstructing food into the stomach, or remove it from the esophagus.
Esophageal food bolus obstruction | Introduction
The net is rolled up on the dorsal side of the pharynx, and it and the trapped particles are drawn into the oesophagus. The gut is U-shaped and also ciliated to move the contents along. The stomach is an enlarged region at the lowest part of the U-bend. Here, digestive enzymes are secreted and a pyloric gland adds further secretions. After digestion, the food is moved on through the intestine, where absorption takes place, and the rectum, where undigested remains are formed into faecal pellets or strings. The anus opens into the dorsal or cloacal part of the peribranchial cavity near the atrial siphon.
Tunicate | Feeding
The pharynx is innervated by the pharyngeal plexus of the vagus nerve. Muscles in the pharynx push the food into the esophagus. The pharynx joins the esophagus at the oesophageal inlet which is located behind the cricoid cartilage.
Human digestive system | Pharynx
Eating and swallowing are complex neuromuscular activities consisting essentially of three phases, an oral, pharyngeal and esophageal phase. Each phase is controlled by a different neurological mechanism. The oral phase, which is entirely voluntary, is mainly controlled by the medial temporal lobes and limbic system of the cerebral cortex with contributions from the motor cortex and other cortical areas. The pharyngeal swallow is started by the oral phase and subsequently is coordinated by the swallowing center on the medulla oblongata and pons. The reflex is initiated by touch receptors in the pharynx as a bolus of food is pushed to the back of the mouth by the tongue, or by stimulation of the palate (palatal reflex).
Swallowing | Coordination and control
This is usually the stomach or part of the large intestine (colon) or jejunum. Reconnection of the stomach to a shortened esophagus is called an esophagogastric anastomosis.
Esophageal cancer | Surgery
Swallowing is a complex mechanism using both skeletal muscle (tongue) and smooth muscles of the pharynx and esophagus. The autonomic nervous system (ANS) coordinates this process in the pharyngeal and esophageal phases. If this goes wrong you might end up with a (hiccup)
Swallowing | Coordination and control
In the colon and esophagus, loss of nervous system control is the major driver of organ dysfunction. Loss of nerves impairs the movement of food through the digestive tract, which can lead to blockage of the esophagus or colon and restriction of their blood supply.
Chagas disease | Pathophysiology
After the obstruction is located, snares or forceps are inserted to pull the food out of the esophagus or to push it into the stomach. The latter is done with caution, usually when the anatomy of the structures around the obstruction is already known.
Schatzki ring | Signs and symptoms
Prior to the following stages of the oral phase, the mandible depresses and the lips abduct to allow food or liquid to enter the oral cavity. Upon entering the oral cavity, the mandible elevates and the lips adduct to assist in oral containment of the food and liquid. The following stages describe the normal and necessary actions to form the bolus, which is defined as the state of the food in which it is ready to be swallowed. 1) Moistening Food is moistened by saliva from the salivary glands (parasympathetic).
Swallowing | Oral phase
When asked where the food is getting stuck, patients will often point to the cervical (neck) region as the site of the obstruction. The actual site of obstruction is always at or below the level at which the level of obstruction is perceived. The most common symptom of esophageal dysphagia is the inability to swallow solid food, which the patient will describe as 'becoming stuck' or 'held up' before it either passes into the stomach or is regurgitated. Pain on swallowing or odynophagia is a distinctive symptom that can be highly indicative of carcinoma, although it also has numerous other causes that are not related to cancer.Achalasia is a major exception to usual pattern of dysphagia in that swallowing of fluid tends to cause more difficulty than swallowing solids.
Dysphagia | Signs and symptoms
Cephalochordates employ a filter feeding system to consume microorganisms. The oral hood serves as the entrance for food particles, and possesses buccal cirri, which assist in sifting out larger food particles before they enter the buccal cavity. Epithelial cilia lining the mouth and pharynx form a specialized "wheel organ" situated at the dorsal and posterior end of the cavity. The motion of the cilia resembles the motion of a turning wheel, hence the organ's name, and transports the captured food particles. Behind this organ is the velum, which acts as an internal filter before food enters the pharynx. The food particles adhere to secreted mucus on the pharyngeal bars before being brought to the epibranchial groove on the dorsal side of the pharynx.
Cephalochordate | Feeding
A muscular ring, called the cardiac sphincter, connects the stomach to the esophagus. This sphincter is very well developed in horses. This and the oblique angle at which the esophagus connects to the stomach explains why horses cannot vomit. The esophagus is also the area of the digestive tract where horses may suffer from the condition known as choke. The esophagus of snakes is remarkable for the distension it undergoes when swallowing prey. 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.
Esophagus | Vertebrates
The esophagus is a muscular tube made of both voluntary and involuntary muscles. It is responsible for peristalsis of food. It is about 8 inches long and passes through the diaphragm before entering the stomach. The esophagus is made up of three layers: from the inside out, they are the mucosa, submucosa, muscularis externa. The mucosa, the inner most layer and lining of the esophagus, is composed of stratified squamous epithelium, lamina propria, and muscularis mucosae. At the end of the esophagus is the lower esophageal sphincter, which normally prevents stomach acid from entering the esophagus. If the sphincter is not sufficiently tight, it may allow acid to enter the esophagus, causing inflammation of one or more layers.
Esophagitis | Mechanism
The main conditions affecting the esophagus are described here. For a more complete list, see esophageal disease.
Esophagus | Clinical significance
The surrounded sac becomes the primitive gut. Sections of this gut begin to differentiate into the organs of the gastrointestinal tract, such as the esophagus, stomach, and intestines. The esophagus develops as part of the foregut tube. The innervation of the esophagus develops from the pharyngeal arches.
Esophagus | Development
The stomach produces gastric acid, a strongly acidic mixture consisting of hydrochloric acid (HCl) and potassium and sodium salts to enable food digestion. Constriction of the upper and lower esophageal sphincters helps to prevent reflux (backflow) of gastric contents and acid into the esophagus, protecting the esophageal mucosa. The acute angle of His and the lower crura of the diaphragm also help this sphincteric action.
Esophagus | Reducing gastric reflux
The diagnosis is generally confirmed by esophageal manometry. DES is present when more than a fifth of swallows results in distal esophageal contractions. NE is present if the average strength of the contractions of the distal esophagus is greater than 180 mmHg but the contraction of the esophagus is otherwise normal.
Esophageal spasm | Diagnosis
Nutcracker esophagus is characterized as a motility disorder of the esophagus, meaning that it is caused by abnormal movement, or peristalsis of the esophagus. People with motility disorders present with two main symptoms chest pain or difficulty with swallowing. Chest pain is the more common. The chest pain is very severe and intense, and mimics cardiac chest pain. It may spread into the arm and back. The symptoms of nutcracker esophagus are intermittent, and may occur with or without food. Rarely, patients can present with a sudden obstruction of the esophagus after eating food (termed a food bolus obstruction, or the 'steakhouse syndrome') requiring urgent treatment.
Nutcracker esophagus | Signs and symptoms
There are two sphincters in the oesophagus. They are normally contracted and they relax when one swallows so that food can pass through them going to the stomach. They then squeeze closed again to prevent regurgitation of the stomach contents. If this normal contraction becomes a spasm, these symptoms begin.
Cricopharyngeal spasm | Physiology
Esophagitis may also occur if an infection is present, which may be due to bacteria, viruses, or fungi; or by diseases that affect the immune system. Irritation can be caused by GERD, vomiting, surgery, medications, hernias, and radiation injury. Inflammation can cause the esophagus to narrow, which makes swallowing food difficult and may result in food bolus impaction.
Esophagitis | Mechanism
If the food that is given is seen to stick to on one side of the throat, which is called food “residue”, that usually means that there is lack of sensation or possibly even a motor/movement problem on that particular side of the throat. The treatment for this discovered throat numbness is to then teach the patient to turn their head to the numb side of their throat when they swallow. This maneuver, called a "head turn" effectively closes off the numb side of the throat so when they swallow the food is only exposed to the normal side of the throat, thereby insuring a safer swallow (on the normal side there is no residue so there is no chance of the residue accidentally falling into the vocal folds and then into the lungs (aspiration).
Flexible Endoscopic Evaluation of Swallowing with Sensory Testing | Technique
There is a palate in the roof of the mouth, separating the breathing passage from the eating area. This suggests an efficient eating mechanism that may indicate a warm-blooded lifestyle.
Ericiolacerta | Introduction
In all gastropods, the portion of the stomach furthest from the oesophagus, called the "style sac", is lined with cilia. These beat in a rotary motion, pulling the food forward in a steady stream from the mouth. Usually, the food is embedded in a string of mucus produced in the mouth, creating a coiled conical mass in the style sac. This action, rather than muscular peristalsis, is responsible for the movement of food through the gastropod digestive tract.
Digestive system of gastropods | Stomach
Both adults and larvae exhibit a "cough" reflex to clear the mouth or throat of debris or items too large to swallow. In larvae the action is mediated by the pharyngeal muscles while in the adult animal it is accomplished by atrial contraction.
Lancelet | Feeding and digestive system
No stomach is present, with the pharynx connecting directly to a muscleless intestine that forms the main length of the gut. This produces further enzymes, and also absorbs nutrients through its single-cell-thick lining. The last portion of the intestine is lined by cuticle, forming a rectum, which expels waste through the anus just below and in front of the tip of the tail. The movement of food through the digestive system is the result of the body movements of the worm. The intestine has valves or sphincters at either end to help control the movement of food through the body.
Nematode | Digestive system
Swallowing involves the coordinated contraction of more than 25 pairs of muscles in the oropharynx, larynx and esophagus, which are active during an oropharyngeal phase, followed by the primary esophageal peristalsis. Swallowing depends on a CPG located in the medulla oblongata, which involves several brain stem motor nuclei and two main groups of interneurons: a dorsal swallowing group (DSG) in the nucleus tractus solitarii and a ventral swallowing group (VSG) located in the ventrolateral medulla above the nucleus ambiguus. Neurons in the DSG are responsible for the generation of the swallowing pattern, while those in the VSG distribute the commands to the various motoneuronal pools.
Central pattern generator | Swallowing
In terminally ill patients, a failure of the reflex to swallow leads to a build-up of mucus or saliva in the throat and airways, producing a noise known as a death rattle (not to be confused with agonal respiration, which is an abnormal pattern of breathing due to cerebral ischemia or hypoxia). Abnormalities of the pharynx and/or oral cavity may lead to oropharyngeal dysphagia. Abnormalities of the esophagus may lead to esophageal dysphagia. The failure of the lower esophagus sphincter to respond properly to swallowing is called achalasia.
Swallowing | Clinical significance
A benign esophageal stricture, or peptic stricture, is a narrowing or tightening of the esophagus that causes swallowing difficulties.
Esophageal stricture | Introduction
In some species, toxic saliva helps to control large prey; when subdued, the food can be torn in pieces by the beak, moved to the oesophagus by the radula, and swallowed. The food bolus is moved along the gut by waves of muscular contractions (peristalsis). The long oesophagus leads to a muscular stomach roughly in the middle of the visceral mass. The digestive gland, which is equivalent to a vertebrate liver, diverticulates here, as does the pancreas, and both of these empty into the caecum, a pouch-shaped sac where most of the absorption of nutrients takes place. Indigestible food can be passed directly from the stomach to the rectum where it joins the flow from the caecum and is voided through the anus into the mantle cavity.
Squid | Digestive system
Closely related to the gag reflex, in which food or other foreign substances are forced back out of the pharynx, swallowing generally pushes food through the digestive system into the stomach. This reflex in particular functions as a protective system for the upper respiratory tract as it not only forces the glottis to close, thereby preventing any substances getting into the airways, but also clears the pharynx of any residual substances by a swallow. This particular reflex is simply one of several aero digestive reflexes, including also the pharyngoglottal closure reflex (in which no swallowing occurs yet the glottis still closes) and the pharyngo-upper esophageal sphincter contractile reflex, which occurs mainly during gastroesophageal reflux episodes.
Pharyngeal reflex | Reflexive pharyngeal swallow
The esophagus is about in length, and carries food to the stomach. A muscular ring, called the cardiac sphincter, connects the stomach to the esophagus. This sphincter is very well developed in horses. This and the oblique angle at which the esophagus connects to the stomach explains why horses cannot vomit. The esophagus is also the area of the digestive tract where horses may suffer from choke.
Equine anatomy | Esophagus
A structure with the same name is often found in invertebrates, including molluscs and arthropods, connecting the oral cavity with the stomach. In terms of the digestive system of snails and slugs, the mouth opens into an esophagus, which connects to the stomach. Because of torsion, which is the rotation of the main body of the animal during larval development, the esophagus usually passes around the stomach, and opens into its back, furthest from the mouth. In species that have undergone de-torsion, however, the esophagus may open into the anterior of the stomach, which is the reverse of the usual gastropod arrangement.
Esophagus | Invertebrates
Sclerosis of the esophagus, such as with systemic sclerosis or in CREST syndrome may cause hardening of the walls of the esophagus and interfere with peristalsis.
Esophagus | Motility disorders
Digestion begins in the mouth. First, the animal selects pieces of forage and picks up finer foods, such as grain, with sensitive, prehensile, lips. The front teeth of the horse, called incisors, nip off forage, and food is ground up for swallowing by the premolars and molars. The esophagus carries food to the stomach. The esophagus enters the stomach at an acute angle, creating a one-way valve, with a powerful sphincter mechanism at the gastroesophageal junction, which is why horses cannot vomit. The esophagus is also the area of the digestive tract where horses may suffer from choke. ("see" Illnesses related to improper feeding "below")
Equine nutrition | Chewing and swallowing
The pharynx forms the first part of the digestive system. The endostyle produces a supply of mucus which is then passed into the rest of the pharynx by the beating of flagella along its margins. The mucus then flows in a sheet across the surface of the pharynx, trapping planktonic food particles as they pass through the stigmata, and is collected in the ridge on the dorsal surface. The ridge bears a groove along one side, which passes the collected food downwards and into the oesophageal opening at the base of the pharynx. The oesophagus runs downwards to a stomach in the abdomen, which secretes enzymes that digest the food.
Ascidiacea | Digestive system
Digestion begins in the mouth, which chews food into smaller pieces for easier digestion. Then it is swallowed, and moves through the esophagus to the stomach. In the stomach, food is mixed with gastric acids to allow the extraction of nutrients. What is left is called chyme; this then moves into the small intestine, which absorbs the nutrients and water from the chyme. What remains passes on to the large intestine, where it is dried to form feces; these are then stored in the rectum until they are expelled through the anus.
Human body | Digestive system
An earthworm's digestive system consists of a mouth, pharynx, esophagus, crop, gizzard, and intestine. The mouth is surrounded by strong lips, which act like a hand to grab pieces of dead grass, leaves, and weeds, with bits of soil to help chew. The lips break the food down into smaller pieces. In the pharynx, the food is lubricated by mucus secretions for easier passage. The esophagus adds calcium carbonate to neutralize the acids formed by food matter decay. Temporary storage occurs in the crop where food and calcium carbonate are mixed. The powerful muscles of the gizzard churn and mix the mass of food and dirt.
Digestion | In earthworms
Clinical investigations include X-rays when swallowing barium, endoscopy, and CT scans. Surgically, the esophagus is difficult to access.
Esophagus | Introduction
Water passes from the mouth into the large pharynx, which is lined by numerous gill-slits. The ventral surface of the pharynx contains a groove called the endostyle, which, connected to a structure known as Hatschek's pit, produces a film of mucus. Ciliary action pushes the mucus in a film over the surface of the gill slits, trapping suspended food particles as it does so. The mucus is collected in a second, dorsal groove, known as the epipharyngeal groove, and passed back to the rest of the digestive tract. Having passed through the gill slits, the water enters an atrium surrounding the pharynx, then exits the body via the atriopore.
Lancelet | Feeding and digestive system
In tetrapods, the pharynx is much shorter, and the esophagus correspondingly longer, than in fish. In the majority of vertebrates, the esophagus is simply a connecting tube, but in some birds, which regurgitate components to feed their young, it is extended towards the lower end to form a crop for storing food before it enters the true stomach. In ruminants, animals with four stomachs, a groove called the "sulcus reticuli" is often found in the esophagus, allowing milk to drain directly into the hind stomach, the abomasum. In the horse the esophagus is about in length, and carries food to the stomach.
Esophagus | Vertebrates
Behind the mouth is a muscular, sclerotised pharynx, which acts as a pump, sucking the food through the mouth and on into the oesophagus and stomach. In some arachnids, the oesophagus also acts as an additional pump. The stomach is tubular in shape, with multiple diverticula extending throughout the body. The stomach and its diverticula both produce digestive enzymes and absorb nutrients from the food. It extends through most of the body, and connects to a short sclerotised intestine and anus in the hind part of the abdomen.
Arachnid | Diet and digestive system
The right crus of the diaphragm loops around forming a sling around the esophagus. Upon inspiration, this sling would constrict the esophagus, forming a functional (not anatomical) sphincter that prevents stomach contents from refluxing up the esophagus when intra-abdominal pressure rises during inspiration.
Esophageal hiatus | Introduction
The lower sphincter helps to prevent reflux of acidic stomach content. The esophagus has a rich blood supply and venous drainage. Its smooth muscle is innervated by involuntary nerves (sympathetic nerves via the sympathetic trunk and parasympathetic nerves via the vagus nerve) and in addition voluntary nerves (lower motor neurons) which are carried in the vagus nerve to innervate its striated muscle. The esophagus may be affected by gastric reflux, cancer, prominent dilated blood vessels called varices that can bleed heavily, tears, constrictions, and disorders of motility. Diseases may cause difficulty swallowing (dysphagia), painful swallowing (odynophagia), chest pain, or cause no symptoms at all.
Esophagus | Introduction
Damage to this nerve may result in difficulties swallowing.
Cranial nerves | Vagus nerve (X)
Megaesophagus may occur secondary to diseases such as achalasia or Chagas disease. Achalasia is caused by a loss of ganglion cells in the myenteric plexus. There is a marked lack of contraction within the muscles involved in peristalsis with a constant contraction of the lower esophageal sphincter. Dilation of the esophagus results in difficulty swallowing. Retention of food bolus is also noted.
Megaesophagus | Humans
An X-ray of swallowed barium may be used to reveal the size and shape of the esophagus, and the presence of any masses. The esophagus may also be imaged using a flexible camera inserted into the esophagus, in a procedure called an endoscopy. If an endoscopy is used on the stomach, the camera will also have to pass through the esophagus. During an endoscopy, a biopsy may be taken. If cancer of the esophagus is being investigated, other methods, including a CT scan, may also be used.
Esophagus | Imaging
As soon as the bolus of food is received in the pharynx, the elevator muscles relax, the pharynx descends, and the constrictors contract upon the bolus, and convey it downward into the esophagus. During deglutition, they contract and cause peristaltic movement in the pharynx.
Inferior pharyngeal constrictor muscle | Action
The digestive system consists of the mouth including the tongue and teeth, esophagus, stomach, (gastrointestinal tract, small and large intestines, and rectum), as well as the liver, pancreas, gallbladder, and salivary glands. It converts food into small, nutritional, non-toxic molecules for distribution and absorption into the body. These molecules take the form of proteins (which are broken down into amino acids), fats, vitamins and minerals (the last of which are mainly ionic rather than molecular). After being swallowed, food moves through the gastrointestinal tract by means of peristalsis: the systematic expansion and contraction of muscles to push food from one area to the next.
Human body | Digestive system
The patient swallows a barium solution, with continuous fluoroscopy (X-ray recording) to observe the flow of the fluid through the esophagus. Normal peristaltic movement of the esophagus is not seen. There is acute tapering at the lower esophageal sphincter and narrowing at the gastro-esophageal junction, producing a "bird's beak" or "rat's tail" appearance. The esophagus above the narrowing is often dilated (enlarged) to varying degrees as the esophagus is gradually stretched over time. An air-fluid margin is often seen over the barium column due to the lack of peristalsis. A five-minutes timed barium swallow can provide a useful benchmark to measure the effectiveness of treatment.
Esophageal achalasia | Barium swallow
The esophagus is one of the upper parts of the digestive system. There are taste buds on its upper part. It begins at the back of the mouth, passing downwards through the rear part of the mediastinum, through the diaphragm, and into the stomach. In humans, the esophagus generally starts around the level of the sixth cervical vertebra behind the cricoid cartilage of the trachea, enters the diaphragm at about the level of the tenth thoracic vertebra, and ends at the cardia of the stomach, at the level of the eleventh thoracic vertebra. The esophagus is usually about 25 cm (10 in) in length.
Esophagus | Structure
Some signs and symptoms of swallowing difficulties include difficulty controlling food in the mouth, inability to control food or saliva in the mouth, difficulty initiating a swallow, coughing, choking, frequent pneumonia, unexplained weight loss, gurgly or wet voice after swallowing, nasal regurgitation, and dysphagia (patient complaint of swallowing difficulty). Other symptoms include drooling, dysarthria, dysphonia, aspiration pneumonia, depression, or nasopharyngeal regurgitation as associated symptoms. When asked where the food is getting stuck patients will often point to the cervical (neck) region as the site of the obstruction.
Oropharyngeal dysphagia | Signs and symptoms
The palate is hard at the front of the mouth since the overlying mucosa is covering a plate of bone; it is softer and more pliable at the back being made of muscle and connective tissue, and it can move to swallow food and liquids. The soft palate ends at the uvula. The surface of the hard palate allows for the pressure needed in eating food, to leave the nasal passage clear. The opening between the lips is termed the oral fissure, and the opening into the throat is called the fauces. At either side of the soft palate are the palatoglossus muscles which also reach into regions of the tongue.
Human digestive system | Mouth
Esophagitis, also spelled oesophagitis, is a disease characterized by inflammation of the esophagus. The esophagus is a tube composed of a mucosal lining, and longitudinal and circular smooth muscle fibers. It connects the pharynx to the stomach; swallowed food and liquids normally pass through it. Esophagitis can be asymptomatic; or can cause epigastric and/or substernal burning pain, especially when lying down or straining; and can make swallowing difficult (dysphagia). The most common cause of esophagitis is the reverse flow of acid from the stomach into the lower esophagus: gastroesophageal reflux disease (GERD).
Esophagitis | Introduction
Eating in handfuls (it can happen with foods as popcorn, different peeled nuts, etc.), requires to chew with more control than normal, and not exceeding in the amounts that enter into the mouth. Having at hand some liquid to drink is useful to help to finish swallowing (before the choking has happened).To swallow well, it is recommended that the neck is in a normal position, straight for the eater's body, with the head looking forward, being seated or standing up (not lying or too reclined).
Choking | Prevention
Nutcracker esophagus, or hypertensive peristalsis, is a disorder of the movement of the esophagus characterized by contractions in the smooth muscle of the esophagus in a normal sequence but at an excessive amplitude or duration. Nutcracker esophagus is one of several motility disorders of the esophagus, including achalasia and diffuse esophageal spasm. It causes difficulty swallowing, or dysphagia, to both solid and liquid foods, and can cause significant chest pain; it may also be asymptomatic. Nutcracker esophagus can affect people of any age, but is more common in the sixth and seventh decades of life. The diagnosis is made by an esophageal motility study (esophageal manometry), which evaluates the pressure of the esophagus at various points along its length.
Nutcracker esophagus | Introduction
As the condition involves alterations in the wall of the esophagus and reduction in the calibre of the esophagus, the symptoms of esophageal intramucosal pseudodiverticulosis are primarily related to swallowing. Difficulty swallowing solids is a typical symptom. In extreme cases, food may become impacted in the esophagus. Some individuals may have bleeding in the esophagus, manifesting as vomiting of blood or as melena stools. With the reduction of oral intake due to difficulty swallowing, affected individuals usually lose weight.
Esophageal intramural pseudodiverticulosis | Signs and symptoms
The digestive system begins with the Aristotle’s lantern, where the food enters the body of the sea urchin. An esophagus extends from the mouth through the center of the Aristotle’s lantern, where it joins up with an intestine. The intestine is arranged in little bundles that adhere to the inside of the test in a counter-clockwise circuit around the Aristotle’s lantern. Once the intestine gets back to itself, it doubles over itself and reverses directions in a second clockwise direction. Digestive enzymes are produced by the intestinal walls and breakdown of food is almost completely extracellular. From the intestine, what is left of the food moves out of the intestine into the short rectum, and out the anus.
Strongylocentrotus droebachiensis | Digestive system
Other tools may be used to remove food boluses. The Roth Net is a mesh net that can be inserted through the endoscope, and opened and closed from the outside; it can be used to retrieve pieces of obstructed food. Snares, which are normally used to remove polyps can be used to macerate the food causing the obstruction. Dormia baskets, which are metal baskets used to remove stones from the common bile duct in a procedure known as endoscopic retrograde cholangiopancreatography, can be opened and closed from the outside in a similar manner to macerate food and facilitate removal. Forceps used for biopsies can also be employed in a similar manner.
Esophageal food bolus obstruction | Endoscopic
The use of glucagon, while common, has not been found to be useful.
Esophageal food bolus obstruction | Introduction
The diagnosis of nutcracker esophagus is typically made with an esophageal motility study, which shows characteristic features of the disorder. Esophageal motility studies involve pressure measurements of the esophagus after a patient takes a wet (fluid-containing) or dry (solid-containing) swallow. Measurements are usually taken at various points in the esophagus. Nutcracker esophagus is characterized by a number of criteria described in the literature. The most commonly used criteria are the Castell criteria, named after American gastroenterologist D.O. Castell. The Castell criteria include one major criterion: a mean peristaltic amplitude in the distal esophagus of more than 180 mm Hg. The minor criterion is the presence of repetitive contractions (meaning two or more) that are greater than six seconds in duration.
Nutcracker esophagus | Esophageal motility studies
The enzymes start to break down the food in the mouth. Chewing, in which the food is mixed with saliva, begins the mechanical process of digestion. This produces a bolus which can be swallowed down the esophagus to enter the stomach. In the stomach the gastric phase of digestion takes place. The food is further broken down by mixing with gastric acid until it passes into the duodenum, in the third intestinal phase of digestion, where it is mixed with a number of enzymes produced by the pancreas. Digestion is helped by the chewing of food carried out by the muscles of mastication, the tongue, and the teeth, and also by the contractions of peristalsis, and segmentation.
Human digestive system | Introduction
Water flowing inwards brings food through the vestibule, between the inner and outer membranes. The vestibule is a passage for both food entrance and waste exit. The vestibular membranes push the food inwards, where they then congregate in a spindle-shaped food vacuole in the pharynx. Once the food vacuoles leave the non-ciliated pharyngeal tube, they become rounded. When the water flows outwards, contractile vacuoles and full food vacuoles may empty their contents. Contractile vacuoles are located between or beside the macronucleus and vestibule.
Vorticella | Feeding
The remainder of the digestive system consists of an oesophagus and intestine; there is no stomach. In some families there are openings in the dorsal surface of the oesophagus connecting to the external surface, through which water from the food can be squeezed, helping to concentrate it. Digestion occurs in the intestine, with food material being pulled through by cilia, rather than by muscular action.
Acorn worm | Digestive system
It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Premastication is sometimes performed by human parents for infants who are unable to do so for themselves. The food is masticated in the mouth of the parent into a bolus and then transferred to the infant for consumption. (Some other animals also premasticate.) Cattle and some other animals, called ruminants, chew food more than once to extract more nutrients. After the first round of chewing, this food is called cud.
Chewing | Introduction
There is no true stomach, so the oesophagus connects directly to the intestine, which runs in a single loop right around the inside of the calyx. The intestine often includes numerous diverticulae, some of which may be long or branched. The end of the intestine opens into a short muscular rectum. This ascends towards the anus, which projects from a small conical protuberance at the edge of the tegmen. Faecal matter is formed into large, mucous-cemented pellets which fall onto the tegmen and thence the substrate.
Crinoid | Feeding
The digestive tube is composed of an esophagus, which divides in two branches (right and left) and that reunite in a single cecum. The intestines end blindly, meaning that there is no anus.
Schistosoma mansoni | Adult
Many foods can lodge themselves in the esophagus, but the most common are meats such as steak, poultry, or pork leading to the colourful description of the phenomenon as steakhouse syndrome. People with food bolus obstruction typically display acute dysphagia (difficulty swallowing), often to the point that they cannot even swallow their saliva, leading to drooling. They may also suffer from chest pain, neck pain, regurgitation of food, or painful swallowing (odynophagia). Patients with esophageal food boluses are also at risk of complications, such as perforation of the esophagus, and aspiration into the lungs. As a result, urgent treatment of patients with high-risk features, or a lengthy duration of symptoms, is recommended.
Esophageal food bolus obstruction | Signs and symptoms
Gullet, or esophagus, is an organ in vertebrates through which food passes. Gullet may also refer to:
Gullet (disambiguation) | Introduction
This disorder has a guarded prognosis, however a successful management technique is vertical feeding in a Bailey Chair.
Megaesophagus | Diagnosis
The word "esophagus" (British English: "oesophagus"), comes from the () meaning "gullet". It derives from two roots "(eosin)" to carry and () to eat. The use of the word oesophagus, has been documented in anatomical literature since at least the time of Hippocrates, who noted that "the oesophagus ... receives the greatest amount of what we consume." Its existence in other animals and its relationship with the stomach was documented by the Roman naturalist Pliny the Elder (AD23–AD79), and the peristaltic contractions of the esophagus have been documented since at least the time of Galen. The first attempt at surgery on the esophagus focused in the neck, and was conducted in dogs by Theodore Billroth in 1871.
Esophagus | History
Eventual weight loss due to reduced appetite and undernutrition is common. Pain behind the breastbone or in the region around the stomach often feels like heartburn. The pain can frequently be severe, worsening when food of any sort is swallowed. Another sign may be an unusually husky, raspy, or hoarse-sounding cough, a result of the tumor affecting the recurrent laryngeal nerve. The presence of the tumor may disrupt the normal contractions of the esophagus when swallowing. This can lead to nausea and vomiting, regurgitation of food and coughing. There is also an increased risk of aspiration pneumonia due to food entering the airways through the abnormal connections (fistulas) that may develop between the esophagus and the trachea (windpipe).
Esophageal cancer | Signs and symptoms
Chewing or mastication is the process by which food is crushed and ground by teeth. It is the first step of digestion, and it increases the surface area of foods to allow a more efficient break down by enzymes. During the mastication process, the food is positioned by the cheek and tongue between the teeth for grinding. The muscles of mastication move the jaws to bring the teeth into intermittent contact, repeatedly occluding and opening. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the food. After chewing, the food (now called a bolus) is swallowed.
Chewing | Introduction
The esophagus is surrounded at the top and bottom by two muscular rings, known respectively as the upper esophageal sphincter and the lower esophageal sphincter. These sphincters act to close the esophagus when food is not being swallowed. The upper esophageal sphincter is an anatomical sphincter, which is formed by lower portion of inferior pharyngeal constrictor, also known as cricopharyngeal sphincter due to its relation with cricoid cartilage of the larynx anteriorly. However, the lower esophageal sphincter is not an anatomical but rather a functional sphincter, meaning that it acts as a sphincter but does not have a distinct thickening like other sphincters.
Esophagus | Sphincters
The esophagus is reduced.
Rotylenchulus reniformis | Morphology
Some swallowers consume a large meal or drink water before performing to give the stomach a more vertical orientation, allowing for easier passage of the sword. Careful focus is required to complete the process without injury, as the sword passes within millimetres of vital body parts such as the aorta, heart and lungs.
Sword swallowing | Anatomy and method
Because of this additional food allotment, females tend to be the larger of the two sexes. This uneven division of resources is called sex allocation. Females showed a positive correlation between body size and increased fecundity, which offers an explanation as to why there is a bias for increased female food provision and body size.
Organ pipe mud dauber | Behaviour