Chyme

Chyme

Chyme (from Greek "χυμός" - khymos, "juice"[1][2]) is the semifluid mass of partly digested food expelled by the stomach into the duodenum.[3]

Also known as chymus, it is the liquid substance found in the stomach before passing through the pyloric valve and entering the duodenum. It results from the mechanical and chemical breakdown of a bolus and consists of partially digested food, water, hydrochloric acid, and various digestive enzymes. Chyme slowly passes through the pyloric sphincter and into the duodenum, where the extraction of nutrients begins. Depending on the quantity and contents of the meal, the stomach will digest the food into chyme anywhere between 40 minutes to a few hours.

With a pH of around 2, chyme emerging from the stomach is very acidic. To raise its pH, the duodenum secretes a hormone, cholecystokinin (CCK), which causes the gall bladder to contract, releasing alkaline bile into the duodenum. The duodenum also produces the hormone secretin to stimulate the pancreatic secretion of large amounts of sodium bicarbonate, which raises the chyme's pH to 7 before it reaches the jejunum. As it is protected by a thick layer of mucus and utilizes the neutralizing actions of the sodium bicarbonate and bile, the duodenum is not as sensitive to highly acidic chyme as the rest of the small intestine.

At a pH of 7, the enzymes that were present from the stomach are no longer active. This then leads into the further breakdown of the nutrients still present by anaerobic bacteria which at the same time help to package the remains. These bacteria also help synthesize vitamin B and vitamin K.


See also

References

  1. ^ Chyme, Online Etymology Dictionary
  2. ^ χυμός, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus Digital Library
  3. ^ chyme, Merriam-Webster Online Dictionary



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  • chyme — [ ʃim ] n. m. • XVe; lat. méd. chymus, gr. khumos « humeur » ♦ Physiol. Bouillie formée par la masse alimentaire au moment où elle passe dans l intestin après avoir subi l action de la salive et du suc gastrique. « tous ces cachets fuseront dans… …   Encyclopédie Universelle

  • chyme — chyme; coe·nen·chyme; col·len·chyme; des·ma·chyme; en·chyme; mes·en·chyme; scle·ren·chyme; par·en·chyme; …   English syllables

  • Chyme — Chyme, n. [L. chymus chyle, Gr. ? juice, like ?, fr. ? to pour: cf. F. chyme. See {Chyle}.] (Physiol.) The pulpy mass of semi digested food in the small intestines just after its passage from the stomach. It is separated in the intestines into… …   The Collaborative International Dictionary of English

  • chyme — early 15c., bodily fluid; c.1600 in specific sense of mass of semi liquid food in the stomach, from L. chymus, from Gk. khymos, nearly identical to khylos (see CHYLE (Cf. chyle)) and meaning essentially the same thing. Differentiated by Galen,… …   Etymology dictionary

  • chyme — ► NOUN Physiology ▪ the fluid which passes from the stomach to the small intestine, consisting of gastric juices and partly digested food. ORIGIN Greek kh mos juice …   English terms dictionary

  • chyme — [kīm] n. [LL chymus < Gr chymos, juice < cheein: see CHYLE] the thick, semifluid mass resulting from gastric digestion of food: it passes from the stomach into the small intestine, where the chyle is formed from it chymous [kī′məs] adj …   English World dictionary

  • chyme — chymous, adj. /kuym/, n. the semifluid mass into which food is converted by gastric secretion and which passes from the stomach into the small intestine. [1600 10; < L chymus < Gk chymós juice, akin to chylós CHYLE] * * * Thick semifluid mass of… …   Universalium

  • Chyme — Le chyme (prononcer chime [ʃim]) est la substance liquide que l on trouve dans l estomac avant le passage de la valve du pylore et l entrée du duodénum. Il consiste en de la nourriture partiellement digérée, de l eau, de l acide chlorhydrique, et …   Wikipédia en Français

  • chyme —   n. semi liquid partly digested food leaving stomach.    ♦ chymiferous, a. containing chyme.    ♦ chymiflcation, n. conversion of food into chyme.    ♦ chymous, a …   Dictionary of difficult words

  • Chyme — A pre digested, acidified mass of food that passes from the stomach into the small intestine. * * * The semifluid mass of partly digested food passed from the stomach into the duodenum. SYN: pulp (3) [TA], chymus. [G. chymos, juice] * * * chyme… …   Medical dictionary

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