The Digestive System全文完整翻譯

全文翻譯全文翻譯IntroductionThedigestiveorgastrointestinaltract(GItract)beginswiththemouth,wherefoodentersthebody,andendswiththeanus,wheresolidwastematerialleavesthebody.IItcontainstheorgansinvolvedintheingestionandothercomponentsinvolvedinthedigestionoffood.Theorgansknownastheaccessorydigestiveglandsaretheliver,gallbladderandpancreas,whichaidintheprocessingoffoodandnutrients.Othercomponentsincludethemouth.salivaryglands,tongue,teethandepiglottis.Theprimaryfunctionsofthedigestivesystemare:ingestion,digestion,absorptionandelimination.(GI從食物進入身體的口腔開始，到固體廢物離開身體的肛門結(jié)束。它:攝取、消化、吸收和消除。AnatomyandPhysiologyofDigestiveSystemTheTeethTheteetharehardorgansfoundalongtheanteriorandlateraledgesofthemouth.Eachtoothismadeofabone-likesubstancecalleddentinandcoveredinalayerofenamel-thehardestsubstanceinthebody.Theteetharedesignedforcuttingandgrindingfoodintosmallerpiecesandarenamedaftertheirparticularrolesintheprocessofmasticationincisorsforcuttingorbitingoffpiecesoffood;caninesfortearing;premolarsandmolarsforchewingandgrinding.消化系統(tǒng)的解剖學(xué)和生理學(xué)牙齒是位于口腔前部和外側(cè)邊緣的硬器官。每顆牙齒都是由一種叫做牙本質(zhì)的類骨物質(zhì)組的碎片，并根據(jù)它們在咀嚼過程中的特殊作用而命名：用于撕裂的犬齒;前臼齒和用于咀嚼和研磨的臼齒。TheTongueThetongueislocatedontheinferiorportionofthemouthjustposteriorandmedialtotheteethItiscoveredbymanyroughpapillaeforgrippingfoodasitismovedbythetongue'smuscles.Italsohelpstopushfoodtowardtheposteriorpartofthemouthforswallowing.肌肉移動時用來抓取食物。它也有助于把食物推向口腔后部吞咽。ThePalateThepalateishardatthefrontofthemouthsincetheoverlyingmucosaliscoveringaplateofbone;beingmadeofmuscleandconnectivetissue,itissofterandmorepliableattheback,anditcanmovetoswallowfoodandliquids.Thesoftpalateendsattheuvula.Posteriorlyitisconnectedwiththemucousmembranecoveringthefloorofthenasalcavity.在鼻腔底部的粘膜相連。TheSalivaryGlandsThesalivaryglandsplayanimportantroleinthemaintenanceofdentalhealthandgeneralmouthlubrication.Therearethreepairsofmainsalivaryglandsandbetween800and1,000minorsalivaryglands,allofwhichmainlyservethedigestiveprocess,withoutwhichspeechwouldbeimpossible.1000個次要唾液腺，它們主要用于消化過程，沒有它們就不可能說話TheEsophagusTheesophagus,amusculartubeconnectingthepharynxtothestomach,carriesswallowedmassesofchewedfoodalongitslength,whichispartoftheupperGItract.Attheinferiorendoftheesophagusisamuscularringcalledtheloweresophagealsphincterorcardiacsphincter,thefunctionofwhichistocloseofftheendoftheesophagusandsqueezefoodinthestomach.食道末端，擠壓胃中的食物。ThestomachThestomachisaJ-shapedorganjoinedtotheesophagusatitsupperendandtotheduodenumatitslowerend.Inanaverageperson,thestomachisaboutthesizeoftheirtwofistsplacednexttoeachother.Itisdividedintofoursections:cardiacregion,fundus,bodyorcorpusandpyloricregion.Gastricacidplaysavitalroleinthedigestiveprocess.Asthesechemicalswoulddamagethestomachwall,mucusissecretedbyinnumerablegastricglandsinthestomach,toprovideaslimyprotectivelayeragainstthedamagingeffectsofthechemicals.Meanwhiletheproteinisbeingdigested,mechanicalchurningoccursthroughperistalsis,wavesofmuscularcontractionsthatmovealongthestomachwall.Thisallowsthemassoffoodtofurthermixwiththedigestiveenzymes.Thepylorusorpyloricregioncontainscountlessglandswhichsecretedigestiveenzymesincludinggastrin.Afteranhourortwoofdigestion,athicksemi-liquidcalledchymeisproduced.Whenthepyloricsphincter,orvalveopens,chymeenterstheduodenumwhereitmixesfurtherwithdigestiveenzymesfromthepancreas,andthenpassesthroughthesmallintestine,wheredigestioncontinues.胃是一個j形的器官，其上端與食道相連，下端與十二指腸相連。一般人的胃大約是兩個緊TheSmallIntestineThesmallintestineismainlyresponsibleforabsorptionofthenutrients.ThelowerGItract,includingthesmallintestineandthelargeintestine,startsatthepyloricsphincterofthestomachandfinishesattheanus.Itisalong,thintubeabout3cmindiameterandabout5to7mlong.Itislocatedjustinferiortothestomachandtakesupmostofthespaceintheabdominalcavity.Theentiresmallintestineiscoiledlikeahoseandtheinsidesurfaceisfullofmanyridgesandfoldswhichareusedtomaximizethedigestionoffoodandabsorptionofnutrients.Whenfoodleavesthesmallintestine,around90%ofallnutrientshavebeenextracted.Thesmallintestineissubdividedintotheduodenum,thejejunumandtheileum.Theduodenum,ahollow,jointedC-shapedtubeconnectingthestomachtothejejunum,isthefirstandshortestsectionofthesmallintestine.Thejejunumcontainscircularfolds,flapsofdoubledmucosalmembranewhichpartiallyandsometimescompletelyencirclethelumenoftheintestine.Thesefoldsandvilliservetoincreasethesurfaceareaofthejejunum,enablinganincreasedabsorptionofdigestedsugars,aminoacidsandfattyacidsintothebloodstream.Thecircularfoldsalsoslowthepassageoffood,givingmoretimefornutrientstobeabsorbed.Thefinal,longest,andnarrowestsectionofthesmallintestineistheileum.Itsfunctionistoabsorbnutrientsfromfoodthathasbeendigestedinthestomachandtheduodenumandthejejunum.35790%c形中空管，是小腸的第一段，也是最短的一能是從食物中吸收已經(jīng)在胃、十二指腸和空腸消化的食物中吸收營養(yǎng)物質(zhì)。TheLargeIntestineThelargeintestine,along,thicktubeabout6cmindiameterandabout1.5mlong,islocatedjustinferiortothestomachandwrapsaroundthesuperiorandlateralborderofthesmallintestine.Itabsorbswaterandcontainsmanysymbioticbacteriathataidinthebreakingdownofwastestoextractsomesmallamountsofnutrients.Itisdividedintofiveparts:cecum,appendix,colon,rectumandanalcanal.Thececumisashort,pouch-likeregionofthelargeintestinethatdescendsfromtheunionoftheileumandthelargeintestine.Itassistsintheformationoffeces:receivingchymefromthelastpartofthesmallintestineandconnectingtotheascendingcolonofthelargeintestine.Itisalsothesiteoftheappendixattachment.Thecolonhasfourdivisions.Intheascendingcolon,bacteriadigestthetransitoryfecalmatterinordertoreleasevitamins.Theintestinalwallabsorbswater,nutrients,andvitaminsfromthefecesanddepositsthesematerialsintoourbloodstream.Thetransversecolonisthelongestregionofthecolonandislocatedbetweentheascendingcolonanddescendingcolon.Itisnamedforthefactthatitcrossestheabdominalcavitytransverselyfromtherightsidetoleftsidejustbelowthestomach.Muchoftheabsorptionandfecesformationtakesplaceinthetransversecolon,makingitaveryimportantregionofthedigestivesystem.Thedescendingcolonisthethirdandpenultimatesegmentofthecolon.Ittransportsfecesfromthetransversecoloninferiorlyalongtheleftsideoftheabdominalcavitytothesigmoidcolon.Thewallsofitabsorbwateraswellasremainingnutrientsandvitaminsfromthefeces,depositingthesevaluablesubstancesintoourbloodstream.Thesigmoidcolonisacurved,S-shapedregionandisthefinalsegmentofthecolon.Ittransportsfecalmatterfromthedescendingcolontotherectumandanus.Fecesarestoredinthesigmoidcolonuntiltheyarereadytobeeliminatedfromthebodythroughtheanalcanal.Theintestinalwallofthesigmoidcolonalsoplaysasmallroleintheabsorptionofwater,nutrientsandvitaminsfromfeces.Rectumisashort,musculartubethatformsthelowestpartofthelargeintestineandconnectsittotheanus.Theanalcanalisbetweenrectumandanus.Itisopenonlyduringdefecation;atothertimesitiskeptclosedbythemusclesoftheanalsphincter.大腸是一根長而粗的管，直徑約6厘米，長約1.5米，位于胃的正下方，環(huán)繞著小腸的上緣和外側(cè)緣。它吸收水分，并含有許多共生細菌，幫助分解廢物，提取少量營養(yǎng)物質(zhì)。:從值的物質(zhì)儲存到我們的血液中。乙狀結(jié)腸是一個彎曲的sTheLiverTheliverisaroughlytriangularaccessoryorganlocatedtotherightofthestomach,justinferiortothediaphragmandsuperiortothesmallintestine.Itweighsabout3poundsandisthesecondlargestorganinthebody.Theliverhasmanydifferentfunctionsinthebody,butthemajorfunctionoftheliverindigestionistheproductionofbileanditssecretionintothesmallintestine.重約3TheGallbladderThegallbladder,asmall,pear-shapedorganlocatedjustposteriortotheliver,whichisusedtostoreandrecycleexcessbilefromthesmallintestinesothatitcanbereusedforthedigestionofsubsequentmeals.后續(xù)食物的消化。ThePancreasThepancreasisalargeglandlocatedjustinferiorandposteriortothestomach.Itisabout6incheslongandshapedlikeshort,lumpysnakewithits"head"connectedtotheduodenumandits"tail"pointingtotheleftwalloftheabdominalcavity.Thepancreassecretesdigestiveenzymesintothesmallintestinetocompletethechemicaldigestionoffoods.重點句式6重點句式ShapeThestomachisaJ-shapedorganjoinedtotheesophagusatitsupperendandtotheduodenumatitslowerend.胃是一個j形的器官，其上端與食管相連，下端與十二指腸相連。Theduodenum,ahollow,jointedC-shapedtubeconnectingthestomachtothejejunum,isthefirstandshortestsectionofthesmallintestine.十二指腸是連接胃和空腸的C形中空管，是小腸的第一段，也是最短的一段。Thececumisashort,pouch-likeregionofthelargeintestinethatdescendsfromtheunionoftheileumandthelargeintestine.盲腸是大腸的一個小的袋狀區(qū)域，從回腸和大腸的連接處向下延伸。ThesigmoidcolonisacurvedS-shapedregionandisthefinalsegmentofthecolon.乙狀結(jié)腸是一個彎曲的sTheliverisaroughlytriangularaccessoryorganlocatedtotherightofthestomach,justinferiortothediaphragmandsuperiortothesmallintestine.肝臟是一個大致呈三角形的附屬器官，位于胃的右側(cè)，僅次于橫膈膜和小腸以上。Thegallbladder,asmall,pear-shapedorganlocatedjustposteriortotheliver,whichisusedtostoreandrecycleexcessbilefromthesmallintestinesothatitcanbereusedforthedigestionofsubsequentmeals.再用于消化隨后的食物。FormItisdividedintofoursectionscardiacregionfundusbodyorcorpusandpyloricregion.胃分為四個部分：幽門區(qū)，胃底，胃體和胃竇。ThelowerGItract,includingthesmallintestineandthelargeintestine,startsatthepyloricsphincterofthestomachandfinishesattheanus.下消化道，包括小腸和大腸，起于胃的幽門括約肌，止于肛門。Thesmallintestineissubdividedintotheduodenumthejejunumandtheileum.小腸又細分為十二指腸、空腸和回腸。Thejejunumcontainscircularfolds,flapsofdoubledmucosalmembranewhichpartiallyandsometimescompletelyencirclethelumenoftheintestine.空腸有環(huán)狀襞,雙層粘膜瓣部分,部分或有時完全包圍腸腔。Itisdividedintofivepartscecum,appendixcolonrectumandanalcanal.大腸分為盲腸、闌尾、結(jié)腸、直腸、肛管五個部分。Rectumisashort,musculartubethatformsthelowestpartofthelargeintestineandconnectsittotheanus.直腸是一個短的肌肉管，形成大腸的最低部，并連接肛門。Othercomponentsincludethemouthsalivaryglandstongueteethandepiglottis.其他組成成分包括嘴，唾液腺，舌頭，牙齒和會厭。Thesalivaryglandsplayanimportantroleinthemaintenanceofdentalhealthandgeneralmouthlubrication.它是由肌肉和結(jié)締組織組成的，背部更柔軟、更柔韌，可以移動來吞咽食物和液體Theesophagus,amusculartubeconnectingthepharynxtothestomach,carriesswallowedmassesofchewedfoodalongitslength,whichispartoftheupperGItract.大量咀嚼過的食物。FunctionAsthesechemicalswoulddamagethestomachwall,mucusissecretedbyinnumerablegastricglandsinthestomach,toprovideaslimyprotectivelayeragainstthedamagingeffectsofthechemicals.化學(xué)物質(zhì)的破壞作用。Thepylorusorpyloricregioncontainscountlessglandswhichsecretedigestiveenzymesincludinggastrin.幽門或幽門區(qū)含有無數(shù)腺體，它們分泌包括促胃液素在內(nèi)的消化酶。Theentiresmallintestineiscoiledlikeahoseandtheinsidesurfaceisfullofmanyridgesandfoldswhichareusedtomaximizethedigestionoffoodandabsorptionofnutrients.養(yǎng)物質(zhì)。Thesmallintestineismainlyresponsibleforabsorptionofthenutrients.小腸主要負責吸收營養(yǎng)物質(zhì)。Thesefoldsandvilliservetoincreasethesurfaceareaofthejejunum,enablinganincreasedabsorptionofdigestedsugars,aminoacidsandfattyacidsintothebloodstream.這些褶皺和絨毛的作用是增加空腸的表面積，從而促進血液中糖、氨基酸和脂肪酸的吸收。Itsfunctionistoabsorbnutrientsfromfoodthathasbeendigestedinthestomachandtheduodenumandthejejunum.回腸的功能是從食物中吸收已經(jīng)在胃、十二指腸和空腸消化的食物中吸收營養(yǎng)物質(zhì)。Itabsorbswaterandcontainsmanysymbioticbacteriathataidinthebreakingdownofwastestoextractsomesmallamountsofnutrients.大腸吸收水分，并含有許多共生細菌，幫助分解廢物，提取少量營養(yǎng)物質(zhì)。Itassistsintheformationoffeces.回腸可以幫助促進糞便的形成。Theintestinalwallabsorbswater,nutrients,andvitaminsfromthefecesanddepositsthesematerialsintoourbloodstream.腸壁從糞便中吸收水分、營養(yǎng)物質(zhì)和維生素，并將這些物質(zhì)運送到我們的血液中。Theorgansknownastheaccessorydigestiveglandsaretheliver,gallbladderandpancreas,whichaidintheprocessingoffoodandnutrients.被稱為附屬消化腺的器官是肝臟、膽囊和胰腺，它們幫助消化食物和營養(yǎng)物質(zhì)。Theprimaryfunctionsofthedigestivesystemare:ingestion,digestion,absorptionandelimination.消化系統(tǒng)的主要功能有:攝取、消化、吸收和消除。Itiscoveredbymanyroughpapillaeforgrippingfoodasitismovedbythetongue'smuscles.Italsohelpstopushfoodtowardtheposteriorpartofthemouthforswallowing.它被許多粗糙的乳頭覆蓋，當它被舌頭的肌肉移動時用來抓取食物。它也有助于把食物推向口腔后部吞咽。Thesalivaryglandsplayanimportantroleinthemaintenanceofdentalhealthandgeneralmouthlubrication.它是由肌肉和結(jié)締組織組成的，背部更柔軟、更柔韌，可以移動來吞咽食物和液體。allofwhichmainlyservethedigestiveprocesswithoutwhichspeechwouldbeimpossible.它們主要用于消化過程，沒有它們就不可能說話。thefunctionofwhichistocloseofftheendoftheesophagusandsqueezefoodinthestomach.食管括約肌其作用是關(guān)閉食道末端，擠壓胃中的食物。PositionItislocatedjustinferiortothestomachandtakesupmostofthespaceintheabdominalcavity.它位于胃的下方，占據(jù)