双语教学中的生物化学词汇

PAGEPAGE2双语生物化学词汇GlossaryofBiochemistryBilinguallyAAbsoluteconfiguration（绝对构型）Theconfigurationoffourdifferentsubstituentgroupsaroundanasymmetriccarbonatom,inrelationtou-andi.-glyceraldehyde.Absorption（吸收）:transportoftheproductsofdigestionfromtheintestinaltractintotheblood.Acceptorcontrol（受体控制）:TheregulationoftherateofrespirationbytheavailabilityofADPasphosphategroupacceptor.Accessorypigments（辅助色素）:Visiblelight-absorbingpigments(carotenoids,xanthophyll,andphycobilins藻胆素)inplantsandphotosyntheticbacteriathatcomplementchlorophyllsintrappingenergyfromsunlight.Acidosis（酸中毒）:Ametabolicconditioninwhichthecapacityofthebodytobufferisdiminished;usuallyaccompaniedbydecreasedbloodpH.Actin（肌动蛋白）:Aproteinmakingupthethinfilaments（细丝）ofmuscle;alsoanimportantcomponentofthecytoskeletonofmanyeukaryoticcells.Activationenergy(ΔG*)（活化能）:Theamountofenergy(injoules)requiredtoconvertallthemoleculesin1moleofareactingsubstancefromthegroundstatetothetransitionstate.Activator:（活化物、激活剂）(1)ADNA-bindingproteinthatpositivelyregulatestheexpressionofoneormoregenes;thatis,transcriptionratesincreasewhenanactivatorisboundtotheDNA.(2)Apositivemodulatorofanallostericenzyme.Activesite:（活性部位）Theregionofanenzymesurfacethatbindsthesubstratemoleculeandcatalyticallytransformsit;alsoknownasthecatalyticsite.Activetransport:（主动运输）Energy-requiringtransportofasoluteacrossamembraneinthedirectionofincreasingconcentration.Activity:（活度）Thetruethermodynamicactivityorpotentialofasubstance,asdistinctfromitsmolarconcentration.Activitycoefficient:（活度系数）Thefactorbywhichthenumericalvalueoftheconcentrationofasolutemustbemultipliedtogiveitstruethermodynamicactivity.Adenosine3',5'-cyclicmonophosphate:SeecyclicAMP.Adenosinediphosphate:SeeADP.Adenosinetriphosphate:SeeATP.Adipocyte:（脂肪细胞）Ananimalcellspecializedforthestorageoffats(triacylglycerols).Adiposetissue:（脂肪组织）Connectivetissuespecializedforthestorageoflargeamountsoftriacylglycerols.ADP(adenosinediphosphate):Aribonucleosidediphosphateservingasphosphategroupacceptorinthecellenergycycle.Aerobe:（需氧生物）Anorganismthatlivesinairandusesoxygenastheterminalelectronacceptorinrespiration.Aerobic:Requiringoroccurringinthepresenceofoxygen.Alcoholfermentation:（乙醇发酵）Theanaerobicconversionofglucosetoethanolviaglycolysis.Seealsofermentation.Aldose:（醛糖）Asimplesugarinwhichthecarbonylcarbonatomisanaldehyde;thatis,thecarbonylcarbonisatoneendofthecarbonchain.Alkalosis:（碱中毒）Ametabolicconditioninwhichthecapacityofthebodytobufferisdiminished;usuallyaccompaniedbyanincreaseinbloodpH.Allostericenzyme:（变/别构效应）Aregulatoryenzyme,withcatalyticactivitymodulatedbythenoncovalentbindingofaspecificmetaboliteatasiteotherthantheactivesite.Allostericprotein:（变/别构蛋白）Aprotein(generallywithmultiplesubunits)withmultipleligand-bindingsites,suchthatligandbindingatonesiteaffectsligandbindingatanother.Allostericsite:（变/别构部位）Thespecificsiteonthesurfaceofanallostericenzymemoleculetowhichthemodulatororeffectormoleculeisbound.αhelix:（α-螺旋）Ahelicalconformationofapolypeptidechain,usuallyright-handed,withmaximalintrachainhydrogenbonding;oneofthemostcommonsecondarystructuresinproteins.Amestest:Asimplebacterialtestforcarcinogens,basedontheassumptionthatcarcinogensaremutagens.Aminoacidactivation:（氨基酸活化）ATP-dependentenzymaticesterificationofthecarboxylgroupofanaminoacidtothe3'-hydroxylgroupofitscorrespondingtRNA.Aminoacids:（氨基酸）anAmino-substitutedcarboxylicacids,thebuildingblocksofproteins.Amino-terminalresidue:（氨基末端残基）Theonlyaminoacidresidueinapolypeptidechainwithafreea-aminogroup;definestheaminoterminusofthepolypeptide.Aminoacyl-tRNA:（氨酰tRNA）AnaminoacylesterofatRNA.Aminoacyl-tRNAsynthetases:（氨酰tRNA合成酶）Enzymesthatcatalyzesynthesisofanaminoacyl-tRNAattheexpenseofATPenergy.Aminotransferases:（氨基转移酶）Enzymesthatcatalyzethetransferofaminogroupsfromα-aminotoα-ketoacids;alsocalledtransaminases.Ammonotelic:（排氨的）Excretingexcessnitrogenintheformofammonia.Amphibolicpathway:（双向代谢途径）Ametabolicpathwayusedinbothcatabolismandanabolism.Amphipathic:（双亲的）Containingbothpolarandnonpolardomains.Ampholyte:（两性电解质）Asubstancethatcanactaseitherabaseoranacid.Amphoteric:（两性的）Capableofdonatingandacceptingprotons,thusabletoserveasanacidorabase.Anabolisim:（合成代谢）Thephaseofintermediarymetabolismconcernedwiththeenergy-requiringbiosynthesisofcellcomponentsfromsmallerprecursors.Anaerobe:（厌氧生物）Anorganismthatliveswithoutoxygen.Obligateanaerobes（专性厌氧生物）diewhenexposedtooxygen.Anaerobic:（厌氧的）Occurringintheabsenceofairoroxygen.Anapleroticreaction:（回补反应）Anenzyme-catalyzedreactionthatcanreplenishthesupplyofintermediatesinthecitricacidcycle.Angstrom(Ǻ):（唉）Aunitoflength(10-8cm)usedtoindicatemoleculardimensions.Anhydride:（酸酐）Theproduct,ofthecondensationoftwocarboxylorphosphategroupsinwhichtheelementsofwaterareeliminatedtoformacompoundwiththegeneralstructureR—X—0—X—R,whereXiseithercarbonorphosphorus.Anion-exchangeresin:（阴离子交换树脂）Apolymericresinwithfixedcationicgroups;usedinthechromatographicseparationofanions.Anomers:（异头物、端基异构体）Twostereoisomersofagivensugarthatdifferonlyintheconfigurationaboutthecarbonyl(anomeric)carbonatom.Antibiotic:（抗生素）Oneofmanydifferentorganiccompoundsthatareformedandsecretedbyvariousspeciesofmicroorganismsandplants,aretoxictootherspecies,andpresumablyhaveadefensivefunction.Antibody:（抗体）Adefenseproteinsynthesizedbytheimmunesystemofvertebrates.Seealsoimmunoglobulin.Anticodon:（反密码子）AspecificsequenceofthreenucleotidesinatRNA,complementarytoacodonforanaminoacidinanmRNA.Antigen:（抗原）Amoleculecapableofelicitingthesynthesisofaspecificantibodyinvertebrates.Antiparallel:（反平行）Describingtwolinearpolymersthatareoppositeinpolarityororientation.Antiport:（反向转运）Cotransportoftwosolutesacrossamembraneinoppositedirections.Apoenzyme:（酶蛋白）Theproteinportionofanenzyme,exclusiveofanyorganicorinorganiccofactorsorprostheticgroupsthatmightberequiredforcatalyticactivity.Apolipoprotein:（脱辅基脂蛋白）Theproteincomponentofalipoprotein.Apoprotein:（脱辅基蛋白）Theproteinportionofaprotein,exclusiveofanyorganicorinorganiccofactorsorprostheticgroupsthatmightberequiredforactivity.Apoptosis:（细胞凋亡）(app'-a-toe'-sis)Programmedcelldeath,inwhichacellbringsaboutitsowndeathandlysis,signaledfromoutsideorprogrammedinitsgenes,bysystematicallydegradingitsownmacromolecules.Arrestin:（抑制蛋白）Afamilyofproteinsthatbindtothephosphorylatedcarboxyl-terminalregionofserpentinereceptors,preventingtheirinteractionswithGproteinsandtherebyterminatingthesignalthroughthosereceptors.Asymmetriccarbonatom:（不对称碳原子）Acarbonatomthatiscovalentlybondedtofourdifferentgroupsandthusmayexistintwodifferenttetrahedralconfigurations.ATP(adenosinetriphosphate):Aribonucleoside5'-triphosphatefunctioningasaphosphategroupdonorinthecellenergycycle;carrieschemicalenergybetweenmetabolicpathwaysbyservingasasharedintermediatecouplingendergonicandexergonicreactions.ATPsynthase:（ATP合酶）AnenzymecomplexthatformsATPfromADPandphosphateduringoxidativephosphorylationintheinnermitochondrialmembraneorthebacterialplasmamembrane,andduringphotophosphorylationinchloroplasts.ATPase:（ATP酶）AnenzymethathydrolyzesATPtoyieldADPandphosphate;usuallycoupledtosomeprocessrequiringenergy.Attenuator:（弱化子）AnRNAsequenceinvolvedinregulatingtheexpressionofcertaingenes;functionsasatranscriptionterminator.Autotroph:（自养生物）Anorganismthatcansynthesizeitsowncomplexmoleculesfromverysimplecarbonandnitrogensources,suchascarbondioxideandammonia.Auxin:（植物生长素）Aplantgrowthhormone.Auxotrophicmutant(auxotroph):（营养缺陷突变体）Amutantorganismdefectiveinthesynthesisofagivenbiomolecule,whichmustthereforebesuppliedfortheorganism'sgrowth.Avogadro'snumber:Thenumberofmoleculesinagrammolecularweight(amole)ofanycompound(6.02×1023).BBack-mutation:（回复突变）Amutationthatcausesamutantgenetoregainitswild-typebasesequence.Bacteriophage(phage):（噬菌体）Aviruscapableofreplicatinginabacterialcell.Basalmetabolicrate:（基础代谢率）Therateofoxygenconsumptionbyananimal'sbodyatcompleterest,longafterameal.Basepair:（碱基对）Twonucleotidesinnucleicacidchainsthatarepairedbyhydrogenbondingoftheirbases;forexample,AwithTorU,andGwithC.βconformation:（β构象）、Anextended,zigzagarrangementofapolypeptidechain;acommonsecondarystructureinproteins.βoxidation:（β氧化）Oxidativedegradationoffattyacidsintoacetyl-CoAbysuccessiveoxidationsattheβ-carbonatom.β-turn:（β转角）Atypeofsecondarystructureinpolypeptidesconsistingoffouraminoacidresiduesarrangedinatightturnsothatthepolypeptideturnsbackonitself.Bilayer:（双分子层）Adoublelayeroforientedamphipathiclipidmolecules,formingthebasicstructureofbiologicalmembranes.Thehydrocarbontailsfaceinwardtoformacontinuousnonpolarphase.Bilesalts:（胆酸盐）Amphipathicsteroidderivativeswithdetergentproperties,participatingindigestionandabsorptionoflipids.Bindingenergy:（吸附能）Theenergyderivedfromnoncovalentinteractionsbetweenenzymeandsubstrateorreceptorandligand.Bindingsite:（结合部位）Thecreviceorpocketonaproteininwhichaligandbinds.Biocytin:（生物胞素）Theconjugateaminoacidresiduearisingfromcovalentattachmentofbiotin,throughanamidelinkage,toaLysresidue.Biomolecule:（生物分子）Anorganiccompoundnormallypresentasanessentialcomponentoflivingorganisms.Biopterin:（生物喋呤）Anenzymaticcofactorderivedfrompterinandinvolvedincertainoxidation-reductionreactions.Biosphere:（生物圈）Allthelivingmatteronorintheearth,theseas,andtheatmosphere.Biotin:（生物素）Avitamin;anenzymaticcofactorinvolvedincarboxylationreactions.Bondenergy:（键能）Theenergyrequiredtobreakabond.Branchmigration:（分支迁移）MovementofthebranchpointinbranchedDNAformedfromtwoDNAmoleculeswithidenticalsequences.SeealsoHollidayintermediate.Buffer:（缓冲液）AsystemcapableofresistingchangesinpH,consistingofaconjugateacid-basepairinwhichtheratioofprotonacceptortoprotondonorisnearunity.CCalorie:（卡）Theamountofheatrequiredtoraisethetemperatureof1.0gofwaterfrom14.5to15.5°C.Onecalorie(cal)equals4.18joules(J).Calvincycle:（Calvin循环）Thecyclicpathwayusedbyplantstofixcarbondioxideandproducetriosephosphates.cAMP:SeecyclicAMP.cAMPreceptorprotein(CRP):（cAMP受体蛋白）Aspecificregulatoryproteinthatcontrolsinitiationoftranscriptionofthegenesproducingtheenzymesrequiredforabacterialcelltousesomeothernutrientwhenglucoseislacking.Alsocalledcatabolitegeneactivatorprotein(CAP)，降解物基因活化蛋白.CAP:Seecatabolitegeneactivatorprotein.Capsid:（衣壳）Theproteincoatofavirionorvirusparticle.Carbanion:（碳负离子）Anegativelychargedcarbonatom.Carbocation:（碳正离子）Apositivelychargedcarbonatom;alsocalledacarboniumion.Carbon-assimilationreactions:（碳同化反应）ReactionsequencesinwhichatmosphericCO2isconvertedintoorganiccompounds.Carbon-fixationreaction:（固碳反应）Thereactioncatalyzedbyrubiscoduringphotosynthesis,orbyothercarboxylases,inwhichatmosphericCO2isinitiallyincorporatedintoanorganiccompound.Carboxyl-terminalresidue:（羧基末端残基）Theonlyaminoacidresidueinapolypeptidechainwithafreea-carboxylgroup;definesthecarboxylterminusofthepolypeptide.Carotenoids:（类葫罗卜素）Lipid-solublephotosyntheticpigmentsmadeupofisopreneunits.Catabolism:（分解代谢）Thephaseofintermediarymetabolismconcernedwiththeenergy-yieldingdegradationofnutrientmolecules.Catabolitegeneactivatorprotein(CAP):SeecAMPreceptorprotein.Catalyticsite:（催化部位）Seeactivesite.Catecholamines:（儿茶酚胺类）Hormones,suchasepinephrine,thatareaminoderivativesofcatechol.Catenane:（连环体）Circularpolymericmoleculeswithanoncovalenttopologicallinkresemblingthelinksofachain.Cation-exchangeresin:（阳离子交换树脂）Aninsolublepolymerwithfixednegativecharges;usedinthechromatographicseparationofcationicsubstances.cDNA:SeecomplementaryDNA.Centraldogma:（中心法则）Theorganizingprincipleofmolecularbiology:geneticinformationflowsfromDNAtoRNAtoprotein.Centromere:（着丝粒）Aspecializedsitewithinachromosome,servingastheattachmentpointforthemitoticormeioticspindle.Cerebroside(脑苷酯)Sphingolipidcontainingonesugarresidueasaheadgroup.Channeling:（生物合成途径限制作用)Thedirecttransferofareactionproduct(commonintermediate)fromtheactivesiteofoneenzymetotheactivesiteofadifferentenzymecatalyzingthenextstepinasequentialpathway.Chemiosmoticcoupling:（化学渗透偶联）CouplingofATPsynthesistoelectrontransferviaanelectrochemicalH+gradientacrossamembrane.Chemotaxis（向化性）:Acell'ssensingofandmovementtoward,orawayfrom,aspecificchemicalagent.Chemotroph:（化能生物）Anorganismthatobtainsenergybymetabolizingorganiccompoundsderivedfromotherorganisms.Chiralcenter:（手性中心）Anatomwithsubstituentsarrangedsothatthemoleculeisnotsuperimposableonitsmirrorimage.Chiralcompound:（手性化合物）Acompoundthatcontainsanasymmetriccenter(chiralatomorchiralcenter)andthuscanoccurintwononsuperimposablemirror-imageforms(enantiomers).Chlorophylls:（叶绿素）Afamilyofgreenpigmentsfunctioningasreceptorsoflightenergyinphotosynthesis;magnesium-porphyrincomplexes.Chloroplasts:（叶绿体）Chlorophyll-containingphotosyntheticorganellesinsomeeukaryoticcells.Chromatin:（染色质）AfilamentouscomplexofDNA,histones,andotherproteins,constitutingtheeukaryoticchromosome.Chromatography:（层析）Aprocessinwhichcomplexmixturesofmoleculesareseparatedbymanyrepeatedpartitioningsbetweenaflowing(mobile)phaseandastationaryphase.Chromosome:（染色体）AsinglelargeDNAmoleculeanditsassociatedproteins,containingmanygenes;storesandtransmitsgeneticinformation.Chylomicron:（乳糜微粒）Aplasmalipoproteinconsistingofalargedropletoftriacylglycerolsstabilizedbyacoatofproteinandphospholipid;carrieslipidsfromtheintestinetothetissues.cisandtransisomers:（顺反异构体）Seegeometricisomers.Cistron:（顺反子）AunitofDNAorRNAcorrespondingtoonegene.Citricacidcycle:（柠檬酸循环）Acyclicsystemofenzymatic.reactionsfortheoxidationofacetylresiduestocarbondioxide,inwhichformationofcitrateisthefirststep;alsoknownastheKrebscycleortricarboxylicacidcycle.Clones:（克隆）Thedescendantsofasinglecell.Cloning:TheproductionoflargenumbersofidenticalDNAmolecules,cells,ororganisms,fromasingleancestralDNAmolecule,cell,ororganism.Closedsystem:（封闭系统）Asystemthatexchangesneithermatternorenergywiththesurroundings.Seealsosystem.Cobalamin:（钴胺素）SeecocnzymeB12.Codon:（密码子）Asequenceofthreeadjacentnucleotidesinanucleicacidthatcodesforaspecificaminoacid.Coenzyme:（辅酶）Anorganiccofactorrequiredfortheactionofcertainenzymes;oftencontainsavitaminasacomponent.CoenzymeA:（辅酶A）Apantothenicacid-containingcoenzymeservingasanacylgroupcarrierincertainenzymaticreactions.CoenzymeB12:Anenzymaticcofactorderivedfromthevitamincobalamin,involvedincertaintypesofcarbonskeletalrearrangements.Cofactor(辅助因子)Aninorganicionoracoenzymerequiredforenzymeactivity.Cognate:（相关的）Describingtwobiomoleculesthatnormallyinteract;forexample,anenzymeanditsnormalsubstrate,orareceptoranditsnormalligand.Cohesiveends:（粘性末端）Seestickyends.Cointegrate:（共整合）AnintermediateinthemigrationofcertainDNAtransposonsinwhichthedonorDNAandtargetDNAarecovalentlyattached.Colligativeproperties:（依数性）Propertiesofsolutionsthatdependonthenumberofsoluteparticlesperunitvolume;forexample,freezing-pointdepression.Commonintermediate:（共同中间产物）Achemicalcompoundcommontotwochemicalreactions,asaproductofoneandareactantintheother.Competitiveinhibition:（竞争性抑制作用）Atypeofenzymeinhibitionreversedbyincreasingthesubstrateconcentration;acompetitiveinhibitorgenerallycompeteswiththenormalsubstrateorligandforaprotein'sbindingsite.Complementary:（互补）Havingamolecularsurfacewithchemicalgroupsarrangedtointeractspecificallywithchemicalgroupsonanothermolecule.ComplementaryDNA(cDNA):ADNAusedinDNAcloning,usuallymadebyreversetranscriptase;complementarytoagivenmRNA.Configuration:（构型）Thespatialarrangementofanorganicmoleculethatisconferredbythepresenceofeither(1)doublebonds,aboutwhichthereisnofreedomofrotation,or(2)chiralcenters,aroundwhichsubstituentgroupsarearrangedinaspecificsequence.Configurationalisomerscannotbeinterconvertedwithoutbreakingoneormorecovalentbonds.Conformation:（构象）Thespatialarrangement,ofsubstituentgroupsthatarefreetoassumedifferentpositionsinspace,withoutbreakinganybonds,becauseofthefreedomofbondrotation.Conjugateacid-basepair:（共扼酸碱对）Aprotondonoranditscorrespondingdeprotonatedspecies;forexample,aceticacid(donor)andacetate(acceptor).Conjugateredoxpair:（共扼氧还对）Anelectrondonoranditscorrespondingelectronacceptorform;forexample,Cu+(donor)andCu2+(acceptor),orNADH(donor)andNAD+(acceptor).Conjugatedprotein:（结合蛋白质）Aproteincontainingoneormoreprostheticgroups.Consensussequence:（一致序列）ADNAoraminoacidsequenceconsistingoftheresiduesthatoccurmostcommonlyateachpositionwithinasetofsimilarsequences.Conservativesubstitution:（保守性置换）Replacementofanaminoacidresidueinapolypeptidebyanotherresiduewithsimilarproperties;forexample,substitutionofGlubyAsp.Constitutiveenzymes:（组成酶）Enzymesrequiredatalltimesbyacellandpresentatsomeconstantlevel;forexample,manyenzymesofthecentralmetabolicpathways.Sometimescalledhouse-keepingenzymes.Contourlength(外形长度):Thelengthofahelicalpolymericmoleculeasmeasuredalongthemolecule'shelicalaxis.Corticosteroids（皮质类固醇激素）Steroidhormonesformedbytheadrenalcortex.Cotransport:（共转运）Thesimultaneoustransport,byasingletransporter,oftwosolutesacrossamembrane.Seeantiport,symport.Coupledreactions:（偶联反应）Twochemicalreactionsthathaveacommonintermediateandthusameansofenergytransferfromonetotheother.Covalentbond:（共价键）Achemicalbondthatinvolvessharingofelectronpairs.Cristae:（嵴）Infoldingsoftheinnermitochondrialmembrane.CRP（cAMP受体蛋白）SeecAMPreceptorprotein.CyclicAMP(cAMP):Asecondmessengerwithincells;itsformationbyadenylylcyclaseisstimulatedbycertainhormonesorothermolecularsignals.Cyclicelectronflow:（循环电子流）Inchloroplasts,thelight-inducedflowofelectronsoriginatingfromandreturningtophotosystemI.Cyclicphotophosphorylation:（循环光合磷酸化）ATPsynthesisdrivenbycyclicelectronflowthroughphotosystemI.Cyclin:（细胞周期蛋白）Oneofafamilyofproteinsthatactivatecyclin-dependentproteinkinasesandtherebyregulatethecellcycle.Cytochromes:（细胞色素）Hemeproteinsservingaselectroncarriersinrespiration,photosynthesis,andotheroxidation-reductionreactions.Cytokine:（细胞因子）Oneofafamilyofsmallsecretedproteins(suchasinterleukinsorinterferons)thatactivatecelldivisionordifferentiationbybindingtoplasmamembranereceptorsinsensitivecells.Cytokinesis:（胞质分裂）Thefinalseparationofdaughtercellsfollowingmitosis.Cytoplasm:（细胞质）Theportionofacell'scontentsoutsidethenucleusbutwithintheplasmamembrane;includesorganellessuchasmitochondria.Cytoskeleton:（细胞骨架）Thefilamentousnetworkprovidingstructureandorganizationtothecytoplasm;includesactinfilaments,microtubules,andintermediatefilaments.Cytosol:（细胞浆）Thecontinuousaqueousphaseofthecytoplasm,withitsdissolvedsolutes;excludestheorganellessuchasmitochondria.DDalton:（道尔顿）Theweightofasinglehydrogenatom(1.66xI0-24g).Darkreactions:（暗反应）Seecarbon-assimilationreactions.Denovopathway:（从头合成）Pathwayforsynthesisofabiomolecule,suchasanucleotide,fromsimpleprecursors;asdistinctfromasalvagepathway.Deamination:（脱氨基作用）Theenzymaticremovalofaminogroupsfrombiomoleculessuchasaminoacidsornucleotides.Degeneratecode:（兼并密码）Acodeinwhichasingleelementinonelanguageisspecifiedbymorethanoneelementinasecondlanguage.Dehydrogenases:（脱氢酶类）Enzymescatalyzingtheremovalofpairsofhydrogenatomsfromtheirsubstrates.Deletionmutation:（删除突变）Amutationresultingfromthedeletionofoneormorenucleotidesfromageneorchromosome.Denaturation:（变性）Partialorcompleteunfoldingofthespecificnativeconformationofapolypeptidechain,protein,ornucleicacid.Denaturedprotein:（变性蛋白）Aproteinthathaslostitsnativeconformationbyexposuretoadestabilizingagentsuchasheatordetergent.Deoxyribonucleicacid;SeeDNA.Deoxyribonucleotides:（脱氧核糖核苷酸）Nucleotidescontaining2-deoxyriboseasthepentosecomponent.Desaturases:（去饱和酶）Enzymesthatcatalyzetheintroductionofdoublebondsintothehydrocarbonportionoffattyacids.Desolvation:（脱水）Inaqueoussolution,thereleaseofboundwatersurroundingasolute.Dextrorotatoryisomer:9右旋异构体）Astercoisomerthatrotatestheplaneofplane-polarizedlightclockwise.Diabetesmellitus:（糖尿病）Ametabolicdiseaseresultingfrominsulindeficiency;characterizedbyafailureinglucosetransportfromthebloodintocellsatnormalglucoseconcentrations.Dialysis:（透析）Removalofsmallmoleculesfromasolutionofamacromolecule,byallowingthemtodiffusethroughasemipermeablemembraneintowater.Differentialcentrifugation:（差速离心）Separationofcellorganellesorotherparticlesofdifferentsizebytheirdifferentratesofsedimentationinacentrifugalfield.Differentiation:（分化）Specializationofcellstructureandfunctionduringembryonicgrowthanddevelopment.Diffusion:（扩散）Thenetmovement,ofmoleculesinthedirectionoflowerconcentration.Digestion:（消化）Enzymatichydrolysisofmajornutrientsinthegastrointestinalsystemtoyieldtheirsimplercomponents.Diploid:（二倍体）Havingtwosetsofgeneticinformation;describingacellwithtwochromosomesofeachtype.Dipole;（双极分子）Amoleculehavingbothpositiveandnegativecharges.Diproticacid:Anacidhavingtwodissociableprotons.Disaccharide:（二糖）Acarbohydrateconsistingoftwocovalentlyjoinedmonosaccharideunits.Dissociationconstant:（解离常数）(1)Anequilibriumconstant(Kd)forthedissociationofacomplexoftwoormorebiomoleculesintoitscomponents;forexample,dissociationofasubstratefromanenzyme.(2)Thedissociationconstant(Ka)ofanacid,describingitsdissociationintoitsconjugatebaseandaproton.Disulfidebridge:(二硫桥)Acovalentcrosslinkbetweentwopolypeptidechainsformedbyacystineresidue(twoCysresidues).DNA(deoxyribonucleicacid)：Apolynucleotidehavingaspecificsequenceofdeoxyribonucleotideunitscovalentlyjoinedthrough3',5'-phosphodiesterbonds;servesasthecarrierofgeneticinformation.DNAchimera:（DNA嵌合）ADNAcontaininggeneticinformationderivedfromtwodifferentspecies.DNAcloning:Seccloning.DNAlibrary:（DNA文库）AcollectionofclonedDNAfragments.DNAligase：（DNA连接酶）Anenzymethatcreatesaphosphodiesterbondbetweenthe3'endofoneDNAsegment,andthe5'endofanother.DNAlooping:（DNA出环）TheinteractionofproteinsboundatdistantsitesonaDNAmoleculesothattheinterveningDNAformsaloop.DNAmicroarray:（DNA微阵列）AcollectionofDNAsequencesimmobilizedonasolidsurface,withindividualsequenceslaidoutinpatternedarraysthatcanbeprobedbyhybridization.DNApolymerase:（DNA聚合酶）Anenzymethatcatalyzestemplate-dependentsynthesisofDNAfromitsdeoxyribonucleoside5'-triphosphateprecursors.DNAreplicasesystem：（DNA复制酶系统）TheentirecomplexofenzymeHandspecializedproteinsrequiredinbiologicalDNAreplication.DNAsupercoiling:（DNA超螺旋化）ThecoilingofDNAuponitself,generallyasaresultofbending,underwinding,oroverwindingoftheDNAhelix.DNAtransposition:（DNA转座）Seetransposition.domain:（结构域）Adistinctstructuralunitofapolypeptide;domainsmayhaveseparatefunctionsandmayfoldasindependent,compactunits.Doublehelix:（双螺旋）Thenaturalcoiledconformationoftwocomplementary,antiparallelDNAchains.Double-reciprocalplot:（双倒数作图）Aplot,of1/Voversus1/[S],whichallowsamoreaccuratedeterminationofVmaxandKmthanaplotofVversus[S];alsocalledtheLineweaver-Burkplot,EE'°:标准还原电位Seestandardreductionpotential.E.coli(Escherichiacoli):（大肠杆菌）Acommonbacteriumfoundinthesmallintestineofvertebrates;themostwell-studiedorganism.Electrochemicalgradient:（电化学梯度）Thesumofthegradientsofconcentrationandofelectricchargeofanionacrossamembrane;thedrivingforceforoxidativephosphorylationandphotophosphorylation.Electrochemicalpotential:（电化学势）Theenergyrequiredtomaintainaseparationofchargeandofconcentrationacrossamembrane.Electrogenic:（生电的）Contributingtoanelectricalpotentialacrossamembrane.Electronacceptor:（电子受体）Asubstancethatreceiveselectronsinanoxidation-reductionreaction.Electroncarrier:（电子载体）Aprotein,suchasaflavoproteinoracytochrome,thatcanreversiblygainandloseelectrons;functionsinthetransferofelectronsfromorganicnutrientstooxygenorsomeotherterminalacceptor.Electrondonor:（电子供体）Asubstancethatdonateselectronsinanoxidation-reductionreaction.Electrontransfer:（电子转移）Movementofelectronsfromsubstratestooxygenviathecarriersoftherespiratory(electrontransfer)chain.Electrophile:（亲电剂）Anelectron-deficientgroupwithastrongtendencytoacceptelectronsfromanelectron-richgroup(nucleophile).Electrophoresis（电泳）:Movementofchargedsolutesinresponsetoanelectricalfield;oftenusedtoseparatemixturesofions,proteins,ornucleicacids.Electroporation:（电穿孔法）Introductionofmacromoleculesintocellsafterrenderingthecellstransientlypermeablebytheapplicationofahigh-voltagepulse.Elongationfactors:（延长因子）Specificproteinsreq