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stomach
stomach saclike dilation in the gastrointestinal tract between the esophagus and the intestines , forming an organ of digestion. The stomach is present in virtually all vertebrate animals and in many invertebrates. In ruminants such as the cow, the stomach is divided into four separate chambers. One of these, called the rumen, breaks down complex plant materials, particularly cellulose. In birds, the stomach forms a thick-walled gizzard that is capable of grinding food. The human stomach is a muscular, elastic, pear-shaped bag, lying crosswise in the abdominal cavity beneath the diaphragm. It is capable of gross alterations in size and shape, depending on the position of the body and the amount of food inside. The stomach is about 12 in. (30.5 cm) long and is 6 in. (15.2 cm) wide at its widest point. Its capacity is about 1 qt (0.94 liters) in the adult. Food enters the stomach from the esophagus, through a ring of muscles known as the cardiac sphincter that normally prevents food from passing back to the esophagus. The other end of the stomach empties into the first section of the small intestine, or duodenum; the pyloric sphincter, which separates the two, remains closed until the food in the stomach has been modified and is in suitable condition to pass into the small intestine. The wall of the stomach is composed of four layers, or tunics: an outer fibrous membrane called the serosa, a three-ply layer of muscle, a submucous layer, and, forming the stomach lining, a mucous layer called the gastric mucosa. The surface of the mucosa is honeycombed with over 35,000 gastric glands and is folded into numerous ridges that almost disappear when the stomach is distended with food. The muscular action of the stomach and the digestive action of the gastric juice convert food in the stomach into a semiliquid state (chyme). The stomach comprises complex interconnections of neurons formed into intrinsic nerve plexuses, including the submucosal, subserous, or myenteric plexuses. The stomach is believed to be independent of the central nervous system. See also digestive system . |
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"stomach." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stomach." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-stomach.html "stomach." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-stomach.html |
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stomach
stomach J-shaped organ, lying to the left and slightly below the diaphragm in human beings; one of the organs of the digestive system. At its upper end, it connects to the gullet (oesophagus), and at the lower end to the small intestine. The stomach itself is lined by three layers of muscle and a folded mucous layer that contains gastric glands. These glands secrete hydrochloric acid that destroys some food bacteria and makes possible the action of pepsin, the enzyme that digests proteins. Gastric gland secretion is controlled by the sight, smell, and taste of food, and by hormonal stimuli, chiefly the hormone gastrin. As the food digests, it is churned by muscular action into a thick liquid state called chyme, at which point it passes into the small intestine.
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"stomach." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stomach." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-stomach.html "stomach." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-stomach.html |
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stomach
stomach The part of the alimentary tract into which the oesophagus (gullet) opens immediately below the diaphragm. A term often used colloquially for belly or abdomen, which it is not; so-called ‘stomach-ache’ arises most commonly from the intestine and is felt near the umbilicus. Pain from the stomach itself is higher — just below the breast bone. The stomach expands to receive a meal, holds it for up to four hours depending on the amount of food, churning it to a pulp and initiating digestion, then passes it on by degrees into the duodenum. These functions depend on its muscular wall and the acid- and enzyme-secreting glands in its lining, all of which are under the control of autonomic nerves.
Stuart Judge See alimentary system. |
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COLIN BLAKEMORE and SHELIA JENNETT. "stomach." The Oxford Companion to the Body. 2001. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. COLIN BLAKEMORE and SHELIA JENNETT. "stomach." The Oxford Companion to the Body. 2001. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O128-stomach.html COLIN BLAKEMORE and SHELIA JENNETT. "stomach." The Oxford Companion to the Body. 2001. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O128-stomach.html |
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stomach
stomach The portion of the vertebrate alimentary canal between the oesophagus and the small intestine. It is a muscular organ, capable of dramatic changes in size and shape, in which ingested food is stored and undergoes preliminary digestion. Cells lining the stomach produce gastric juice, which is thoroughly mixed with the food by muscular contractions of the stomach. The resultant acidic partly digested food mass (chyme) is discharged into the duodenum through the pyloric sphincter for final digestion and absorption. Some herbivorous animals (see Ruminantia) have multichambered stomachs from which food is regurgitated, rechewed, and swallowed again.
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"stomach." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stomach." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-stomach.html "stomach." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-stomach.html |
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stomach
stomach internal pouch or cavity of the body in which food is digested; abdomen, †chest; appetite for XIV; †seat of emotion; †temper, disposition XVI; †courage, pride, anger. ME. stomak — OF. stomaque, (also mod.) estomac — L. stomachus — Gr. stómakhos throat, gullet, mouth of an organ, as of the stomach, (later) stomach, f. stóma mouth.
So stomach vb. †take offence; †offend, incite XVI; put up with, brook XVII. orig. — F. s'estomaquer (refl.) be offended, L. stomachārī be resentful, be angry with. stomachic XVII. — F. or late L. — Gr. |
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T. F. HOAD. "stomach." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stomach." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stomach.html T. F. HOAD. "stomach." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stomach.html |
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stomach
stomach (stum-ăk) n. a distensible saclike organ that forms part of the alimentary canal between the oesophagus and the duodenum. The stomach lies just below the diaphragm, to the right of the spleen. Its function is to continue the process of digestion that begins in the mouth. Gastric juice, secreted by gastric glands in the mucosa, together with the churning action of the muscular layers of the stomach, reduces the food to a semiliquid partly digested mass that passes on to the duodenum.
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"stomach." A Dictionary of Nursing. 2008. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stomach." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O62-stomach.html "stomach." A Dictionary of Nursing. 2008. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-stomach.html |
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stomach
stomach an army marches on its stomach a group of soldiers or workers can only fight or function effectively if they have been well fed. Proverbial, translating French c'est la soupe qui fait le soldat, a maxim of Napoleon.
a strong stomach an ability to see or do unpleasant things without feeling sick or squeamish. See also the pit of one's stomach, the way to a man's heart is through his stomach. |
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ELIZABETH KNOWLES. "stomach." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. ELIZABETH KNOWLES. "stomach." The Oxford Dictionary of Phrase and Fable. 2006. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O214-stomach.html ELIZABETH KNOWLES. "stomach." The Oxford Dictionary of Phrase and Fable. 2006. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O214-stomach.html |
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stomach
stomach The anterior region of the gut, enlarged and usually with muscular walls that churn food, and with cells in the lining that secrete digestive acids.
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MICHAEL ALLABY. "stomach." A Dictionary of Zoology. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "stomach." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O8-stomach.html MICHAEL ALLABY. "stomach." A Dictionary of Zoology. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-stomach.html |
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stomach
stomach
•elegiac • Newark • Lubbock
•Caradoc, haddock, paddock, shaddock
•Marduk • piddock • Norfolk • Suffolk
•charlock
•hillock, pillock
•lilac
•ballock, pollack, pollock, rowlock
•bullock • hammock
•hummock, slummock, stomach
•bannock, Zanuck
•Kilmarnock • Greenock • monarch
•eunuch
•arrack, barrack, Baruch, carrack
•cassock, hassock
•tussock • Taoiseach • mattock
•buttock, futtock
•havoc • bulwark • wazzock • Isaac
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"stomach." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stomach." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-stomach.html "stomach." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-stomach.html |
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