第1題Theexperimentof15NlabeledDNAwascarriedoutbyMeselsonandStahlin1958thatfirstproves()AthatDNAcanbereplicated.BthatDNAgenecantransfertomRNA.CthatDNAgenecanexpressprotein.DthemechanismofDNAsemiconservativereplication.EthemechanismofDNAconservativereplication.第2題WhichoneiscorrectaboutOkazakifragments?()AThereareOkazakifragmentsineachnewstrandsofDNABTheOkazakifragmentsarelongerinprokaryotesthanineukaryotesCThegenerationofOkazakifragmentsdonotrequireRNAprimer.DOkazakifragmentsareproducedbyDNApol

IEOkazakifragmentsaretheRNAsegmentscatalyzedbyprimase.第3題ThegenerationofOkazakifragmentsisbecause()AeukaryoteshavemultipleinitiationsitesofDNAreplication.BthevelocityofDNAreplicationistoofast.CthesynthesisofRNAprimersisinsufficient.Dthedirectionofthereplicationoflaggingstrandsisoppositetothatofunwinding.EthelackofDNAligase.第4題IntheprocessofDNAreplication,thenewstrandisthat()Athedirectionofonestrandis5′→3′,theotheris3′→5′.Bthedirectionofthetwostrandsis3′→5′.Cthedirectionofthetwostrandsis5′→3′.Dbothstrandsaresynthesizedinacontinuousfashion.Ebothstrandsaresynthesizedinadiscontinuousfashion.第1題WhichoneiscorrectaboutprokaryoticDNA-pol?()ADNA-polIIIisthepolymerasethathasthelargestamountincell.BDNA-polIIIhas5′→3′polymerizingactivityand3′→5′exonucleaseactivity.CAllarefatalaftergenemutation.DDNA-polIistheprimarypolymerase.EDNA-polIIIhasthefunctionofremovingprimer.第2題WhichoneiscorrectabouteukaryoticDNA-pol?(

)ADNA-polδissimilarwithDNA-pol

IBDNA-polγhasthefunctionofrepairduringreplication

CDNA-polεistheprimarycatalyzedenzymeintheelongationofreplication

DDNA-polβistheenzymeofmitochondrialDNAsynthesis

EDNA-polαhastheprimaseactivity

正確答案：E第3題AboutE.coliDNApolymeraseⅠ,thecorrectdepictionisthat(

)Aithasnoexonucleaseactivity.Bithasendonucleaseactivity.CitistheprimaryenzymeinvolvedinE.coliDNAreplicationDithasarealtimeproofreadingfunctionEtheshortersegmentwhichderivefromhydrolysisofDNApolymeraseⅠiscalledKlenowfragment.Problems：EnzymesandproteinfactorsrequiredinDNAreplication第1題Whichenzymecannotcatalyzetheformationofphosphodiesterlinkage?()ADNA-polIIIBDNA-polICDNAligaseDtopoisomeraseEhelicase正確答案：E第2題ThefunctionofDNAtopoisomeraseis()AtounwindDNAdoublehelix.BtorelievethesupercoilingduringDNAunwinding.Ctohydrolyzeprimers,prolongandlinkDNAsegments.DtoidentifytheoriginsiteofDNAreplication.Etostabilizetheunwindhelix.第3題ThefunctionofDNAligaseis()AtorelievetorsionalstraingeneratedbyDNAunwinding.BtosynthesizeRNAprimer.CtoformDNAsuperhelix.DtocatalyzethejoiningoftheendsoftwofragmentsofDNA.Etoremoveprimersandfillingaps.第4題Whichoneiswrongaboutprimase?

(

)AItcancatalyzethesynthesisofRNAprimers.BThematerialisNTP.CThetemplateisonepartofunwindingDNA.DThestartingofprimaserequiresdnaB.EThesynthesisofRNAprimeris3′→5′.正確答案：EProblems：DNAreplicationinprokaryotes第1題ThefunctionofRNAprimerintheprocessofreplicationis()AtoactivateDNA-polIII.BtoundothedoublestrandDNA.Ctooffer5′terminalendswhichactasthebeginningofnewDNA.Dtooffer3′terminalendswhichactasthebeginningofnewDNA.Etooffer3′terminalactasthebeginningofnewRNA.第2題WhichenzymehasnouseforDNAreplication?()ADNA-dependentDNApolymeraseBDNA-dependentRNApolymeraseCDNAligaseDtopoisomeraseErestrictionendonuclease正確答案：E第3題Theproductofreplicationis5′-GCTAGAT-3′,thenthetemplateis()A5′-GCTAGAT-3′.B5′-CGATCTA3′C3′-CGATCTA-5′D3′-GCTAGAT-5′E5′-CGAUCUA-3′Problems：DNAreplicationineukaryotes第1題Whichoneisnotcorrectabouttelomerase?()ATelomerasehastheactivityofreversetranscriptase.BTelomeraseisthepolymerofDNAandprotein.CThefunctionoftelomeraseistokeeptheintegrityofeukaryoticDNA.DThedeclineoftelomeraseactivityisrelatedtocellaging.EThecatalyticmechanismoftelomeraseisdescribedasinchwormmodel.Problems：DNAReplication-6ReverseTranscription第1題Reversetranscriptionis()AtheDNAbiosynthesisusingRNAastemplate.BtheRNAbiosynthesisusingDNAastemplate.CtheproteinbiosynthesisusingRNAastemplate.DtheprocessofproteinusingDNAastemplateDNAEtheprocessofRNAusingproteinastemplate.Problems：DNATemplateandPromoterinTranscription第1題ThesequenceofsensestrandonDNAis5′GTCAACTAG3′,thetranscriptionproductsis()A5′-TGATCAGTC-3′.B5′-CUAGUUGAC-3′.C5′-CAGUUGAUC-3′.D5′-CTGACTAGT-3′.E5′-GACCUAGUU-3′.第2題Whichiscorrectoneaboutasymmetrictranscription?()Atranscriptionafterbidirectionalreplication.Btranscriptiononthesametemplatestrandappearsboth5′→3′and3′→5′directions.Ctemplatestrandisn’talwaysonthesameDNAstrand.Daftertranscriptionandtranslation,thepolypeptideincludesasymmetric“C”atom.Etranscriptionwithoutregularpattern.第3題Transcriptionandreplicationhavesomesimilarities,butexceptthat()ADNAistemplatestrandBthebondbetweenthetwonucleotides.CtheenzymesarebothDNA-dependent.Dtwocomplementarystrandsaresynthesizedatthesametime.Eobeythebasecouplingrules.Problems：RNAPolymerase第1題Whichonecanrecognizethepromoter?()AαsubunitofRNApolymeraseBβsubunitofRNApolymeraseCβ′subunitofRNApolymeraseDσsubunitofRNApolymeraseEdnaBprotein第2題Ineukaryotes,thetranscriptionproductsofRNApolymeraseⅡis()AhnRNA.B18SrRNA.C28SrRNA.DtRNA.EalloftheRNA.第3題WhichenzymecancatalyzethetranscriptionoftRNAand5SrRNA?(

)ARNApolymeraseⅠBreversetranscriptaseCRNApolymeraseDRNApolymeraseholoenzymeERNApolymeraseⅢ正確答案：E第4題RifampicinisthespecificinhibitorofRNApolymerase,thebindingsiteis()Aβsubunit.Bαsubunit.Cβ′subunit.Dσsubunit.Eωsubunit.第5題45S-rRNAis()ArRNAofbigsubunitofribosome.BrRNAofsmallsubunitofribosome.Cpre-RNAofrRNAexceptfor5SRNA.Dpre-RNAofrRNAexceptfor5.8SRNA.Econsistsofdifferenttranscriptionproducts.Problems：ProkaryoticTranscription第1題Thefunctionofρfactoris()Atobindwithinhibitoronpromoter.BtoincreasethevelocityofRNAsynthesis.CtoreleaseRNApolymerasefrompromoter.Drelatedtotheterminationoftranscription.Etopermitinitiationofspecifictranscription.第2題ThePribnowboxofprokaryoteis()AtheinitiationsiteoftranscriptionBtheinitiationsiteoftranslationCthesitewhereRNApolymeraseandDNAtemplatestrandcanbindstably.DtheactivecenterofDNApolymeraseEtheinitiationsiteofDNAsynthesis第3題Intheelongation,thebindingbetweenRNApolymeraseandDNAtemplatestrand:()AholoenzymebindswiththetemplatestrandBlooselybindingwhichmakesmovementeasily.Cfirmlybinding.Dcoreenzymecanbindtothespecificsiteoftemplatestrand.Esameasthestateofinitiation.Problems：EukaryoticTranscription第1題Transcriptionfactoris()Acomponentsofpolymeraseinprokaryotes.Bcomponentsofpolymeraseineukaryotes.Cincludesα,β,γsubunits.Dtrans-actingfactoringeneexpressionregulation.Epromotoroftheeukaryotictranscription.第2題Pre-initiationcomplex()ofeukaryotesis()ARNApolymeraseandTATAATsequences.BRNApolymerasebindtoTATAsequences.CthetranscriptionfactorsinteractwitheachotherandbindwithRNApolymeraseandDNAtemplatestrand.DαfactorbindwithRNApolymerase.Erepressordissociatesfromoperoncomplexafterallosterism.正確答案：CC第3題Thetranscriptionfactors(TFI,TFII,TFIII)arenamedaccordingto()AincludingI,II,IIIsubunits.BRNApolymeraseI,II,IIIineukaryotes.CthetranscriptedgenesareI,II,III.DactiononGC,CAAT,TATAsequencesrespectively.Eactionontherepressorgene,-35regionand-10region.Problems：RNAProcessing第1題hnRNAsplicingineukaryotesdependson()AsnRNA.Brestrictionendonuclease.Cribozyme.Dprotease.ERNase.第2題Exonis()ADNAsequenceswhichdon’ttranscriptBmutationofgeneCnoncodingregionoftheeukaryoticstructuregene.Dcodingregionoftheeukaryoticstructuregene.EsplitDNAfragments.第3題Thepost-transcriptionalprocessingofhnRNAincludesthelistedthingsexceptfor(

)Acappingat5′-end.Btailingat3′-endwithpolyACmethylationDphosphorylationEspliceintronsandligateexonsProblems：Geneticcodon第1題Thereadingdirectionofgeneticcodonis()Anodirections.B3′→5′.C5′→3′.DNterminus→Cterminus.ECterminus→Nterminus.第2題Whichcodonisboththeinitiationcodonandthecodonformethionine?()ACUUBACGCCAGDAUGEUCG第3題Whichpropertyofgeneticcodoniscorrelatedtoframeshiftmutation?()AcommalessBdegeneracyCwobbleDuniversalEAlloftheaboveisnotcorrect.Problems：Systemofproteinsynthesis第1題Whichiscorrectaboutproteinbiosynthesis?()ADirectionis3′endto5′endonmRNA.BDirectionisNterminustoCterminus.CDirectionisCterminustoNterminus.DDirectedby28SrRNA.EDirectedby4SrRNA.第2題Inmammaliancells,theproteinbiosynthesisislocatedon()Anucleus.BGolgiosome.Cnucleole.Dribosome.Elysosome.第3題ThefunctionoftRNAinproteinbiosynthesisis()Atobindanaminoacidtoanotheraminoacid.BtotransferaminoacidstothecertainsiteofmRNA.Ctoincreasethevalidconcentrationofaminoacids.DtolinkmRNAtoribosome.Etohavethefunctionofaminoacyl-tRNAsynthetase.Problems：Activationofaminoacids第1題Howmanyhighenergyphosphatebondsareusedineachaminoacidactivation?()A1B2C3D4E5第2題WhichistheformylgroupdonorofN-formylmethionine?()AN5,N10-CH2-FH4BN10-CH=NH-FH4CCODN10-CHO-FH4EN5,N10=CH-FH4第3題Aminoacyl-tRNAsynthetase()Aexistsinnucleus.Bhasspecificityonlytoaminoacidsrecognizable.ChasspecificityonlytotRNA.DhasspecificitytobothaminoacidsandtRNA.EneedsGTPforcatalyzingreaction.Problems：InitiationofProteinSynthesis第1題WhichoneisnotcorrectaboutprokaryoticS-DsequenceofmRNA?()AAGGAisthecoresequence.BTheonewhodiscoveredS-DsequenceisShine-Dalgarno.CIt’scomplementarysequencewith3′endof16S-rRNA.DItneedeIF.EItisalsocalledbindingsiteofribosome.第2題Thecorrectoneabouteukaryoticproteinbiosynthesisis()A70Sribosomeentertheribosomecyclefirst.B70Sribosomecan’tenterribosomecycle.C50Ssubunitentertheribosomecyclefirst.D60Ssubunitentertheribosomecyclefirst.E80Sribosomeenterribosomecycleafteritsdissociation.第3題FormationoftheribosomalinitiationcomplexforbacterialproteinsynthesisdoesNOTrequire:()AEF-Tu.BformylmethionyltRNAfMet.CGTP.Dinitiationfactor2(IF-2).EmRNA.Problems：ElongationofProteinSynthesis第1題Thecorrectoneaboutpeptidyltransferaseis()Atheproteinonthesmallsubunitofribosome.Btocatalyzetheformationofpeptidebonds.Ctoactintranslocationprocess.DitneedATPincatalyzing.EitneedGTPincatalyzing.第2題ThefunctionofEF-Tuis()Asynthesisofaminoacyl-tRNA.Btoaccelerateaminoacyl-tRNAenteringAsiteanddegradingGTP.Ctoregulatepeptidebondformation.Dactivityoftranslocase.EacceleratethereleasingoftRNA.第3題InbacteriatheelongationstageofproteinsynthesisdoesNOTinvolve:（）Aaminoacyl-tRNAs.BEF-Tu.CGTP.DIF-2.Epeptidyltransferase.Problems：TerminationofProteinSynthesis第1題Theterminationsignalsare()AAAACCCGGG.BUAAUAGUGA.CUCAAUGAGU.DUUUUUCUUG.ECCACCGCCU.第2題Inproteinbiosynthesis,thenumberofhighphosphatebondsconsumedforonepeptidebondformationis()A5B2C3D1E4正確答案：E第3題Polysomemeansmany()Aribosomes.BribosomesbindtoonemRNAandsynthesizepolypeptides.Csmallsubunitsofribosome.Dbigsubunitsofribosome.Esmallsubunitsofribosomewithaminoacyl-tRNA.Problems：Posttranslationalprocessing第1題Thepost-translationprocessingdoesNOTinclude()AsubunitpolymerizationBmodificationofNterminusofpeptideCcovalentmodificationofsomeaminoacidsDsecretaryproteintargetingEproteindenaturation正確答案：EProblems：IntroductionandProkaryoticDNA-BindingProteins第1題Whatisthegenome?AThecompletesetofgeneticmaterialofanorganismBThesetofgenesthatareexpressedinaspecifictissueCThesetofproteinsthatareinvolvedinDNAreplicationDThesetofenzymesthatareinvolvedinproteinsynthesis第2題Whichofthefollowingisanexampleofaconstitutivegene?AGenesinvolvedincelldifferentiationBGenesinvolvedinresponsetostressCGenesinvolvedinbasiccellularfunctionssuchasmetabolismDGenesinvolvedinimmuneresponse第3題Whatisthemainfunctionofhousekeepinggenes?A

ToregulategeneexpressionBTorespondtoenvironmentalstressCTomaintainbasiccellularfunctionsDTocontrolcelldifferentiation第4題Whatisinductioningeneexpression?ATheprocessbywhichgenesareturnedoffinresponsetoastimulusBTheprocessbywhichgenesareturnedoninresponsetoastimulusCTheprocessbywhichgenesaremutatedDTheprocessbywhichgenesaredeleted第5題RegulatedExpressionofGenesisRequiredfor?ADevelopmentBDifferentiationCAdaptationDAlloftheaboveProblems：Lacoperon第1題WhatdoyoupredictwouldhappenifyoureplacetheLacoperator

DNAfromtheLacoperonwiththeDNAfromtheoperatorregionfromthetryptophanoperon?AThepresenceoflactosewillnotcauseallostericchangestotheLacrepressorBTheLacoperonwillnotbetranscribedwhentryptophanlevelsarehighCThelackofglucosewillnolongerallowCAPbindingtotheDNADRNApolymerasewillonlybindtotheLacpromoterwhenlactoseispresent第2題Thelacoperonconsistsof:AApromoter,anoperator,andthreestructuralgenesBApromoter,anoperator,andonestructuralgeneCApromoterandthreestructuralgenesDAnoperatorandthreestructuralgenes第3題Therepressorproteinforthelacoperonbindsto:AThepromoterregionBTheoperatorregionCThestructuralgenesDTheregulatorygenes第4題Thelacoperonisanexampleof:APositiveregulationBNegativeregulationCBothpositiveandnegativeregulationDNoregulation第5題Thetworegulatoryproteinsthatcontrolthelacoperonare:ACAPandRNApolymeraseBCAPandLacZCLacIandLacZDLacIandCAPProblems：Theλrepressor第1題Thelysogenicpathwayisaprocessbywhich:ABacteriareplicatetheirDNABBacteriaundergocelldivisionCViralDNAintegratesintothehostcell'sgenomeDViralDNAreplicatesindependentlyofthehostcell'sgenome第2題Theλrepressorisinvolvedintheregulationofthe:ALyticpathwayBLysogenicpathwayCBoththelyticandlysogenicpathwaysDNeitherthelyticnorlysogenicpathways第3題TheCroproteinbindstoaspecificDNAsequenceknownasthe:AOperator1(OR1)BOperator2(OR2)CPromoterDEnhancer第4題TheCroproteinisanexampleofa:ARegulatoryproteinBStructuralproteinCEnzymeDLipid第5題Thelyticpathwayischaracterizedby:AThereleaseofviralparticlesfromthehostcellBThemaintenanceofastablerelationshipbetweenthevirusandthehostcellCThereplicationoftheviruswithinthehostcellDTheintegrationofviralDNAintothehostcell'sgenomeProblems：Tryptophanoperon第1題TheTryptophanoperonisasystemofgenesinvolvedinthebiosynthesisoftheaminoacidtryptophan.Itisfoundin:ABacteriaBFungiCPlantsDAnimals第2題TheTryptophanoperonisanexampleofa(n):AInducibleoperonBRepressibleoperonCConstitutiveoperonDTranscriptionfactor第3題Whatisattenuation?ATheincreaseinsignalstrengthasittravelsthroughamediumBThedecreaseinsignalstrengthasittravelsthroughamediumCThereflectionofasignaloffofasurfaceDTheabsorptionofasignalbyareceiver第4題Attenuationisaregulatorymechanismthatcontrolsgeneexpressionatthelevelof:ADNAreplicationBTranscriptionCTranslationDPost-translationalmodification第5題ThefollowingstatementabouttryptophanoperonregulationiscorrectAInthepresenceoftryptophan,onlytheprecursormRNAisproducedBWhenleuco-aminoacid,transcriptionalinhibitionCIstheregulationoftranslationlevelDHasananti-terminationeffectEWhentryptophanispresent,itissuppressedProblems：EukaryoticCis-actingelements第1題1.

Whichofthefollowingisakeydifferencebetweentranscriptioninprokaryotesandeukaryotes?AEukaryotictranscriptionoccursinthenucleus,whileprokaryotictranscriptionoccursinthecytoplasmBEukaryotictranscriptionrequirestheuseofmultipleRNApolymerases,whileprokaryotictranscriptiononlyusesoneCEukaryotictranscriptioninvolvestheprocessingofpre-mRNA,whileprokaryotictranscriptiondoesnotDEukaryotictranscriptionrequirestheuseofaprimer,whileprokaryotictranscriptiondoesnot第2題Whatarecis-actingelements?ADNAsequencesthatregulatetheexpressionofgenesonthesamechromosomeBProteinsthatbindtoDNAandregulategeneexpressionCRNAmoleculesthatinteractwithotherRNAstoregulategeneexpressionDDNAsequencesthatregulatetheexpressionofgenesondifferentchromosomes第3題Whichofthefollowingisnotatypeofcis-actingelement?AEnhancerBSilencerCPromoterDTranscriptionfactor第4題Whichofthefollowingisnotacomponentofapromoter?ATATAboxBEnhancerCCAATboxDGCbox第5題WhichenzymerecognizestheTATAbox?ARNApolymeraseIBRNApolymeraseIICRNApolymeraseIIIDDNApolymeraseProblems：EukaryoticTranscriptionFactors第1題WhichofthefollowingisNOTafunctionoftranscriptionfactors?ABindingtoenhancersorpromoterstoactivateorrepressgeneexpressionBRecruitingRNApolymerasetoinitiatetranscriptionCSplicingRNAtoremoveintronsDModifyingchromatinstructuretomakegenesmoreorlessaccessibletotranscriptionmachinery第2題Homeodomainproteinsarecharacterizedby:AAhelix-turn-helixmotifBAzincfingermotifCAleucinezippermotifDAbeta-sheetmotif第3題Thezinc-fingerdomaincontains:AAzincionthatmediatesprotein-DNAinteractionsBAhelix-turn-helixmotifthatbindstoDNACBothaandbDNeitheranorb第4題Nuclearhormonereceptorsareactivatedby:ALipidsBProteinsCCarbohydratesDNucleicacids第5題Theligand-bindingdomainofanuclearhormonereceptorislocated:AInsidethenucleusBInthecytoplasmCInthecellmembraneDIntheGolgiapparatusProblems：ChromatinRemodeling第1題Howmanytypesofhistonesarethereinanucleosome?AOneBTwoCThreeDFour第2題Whatistheeffectofhistoneacetylationonchromatinstructure?AItloosensthestructureofchromatinBIttightensthestructureofchromatinCIthasnoeffectonchromatinstructureDItdegradesthehistoneproteins第3題WhatisthedifferencebetweenHATsandHDACs?AHATsaddacetylgroupstohistones,whileHDACsremovethemBHATsaddmethylgroupstohistones,whileHDACsremovethemC

HATsaddphosphategroupstohistones,whileHDACsremovethemDHATsaddubiquitingroupstohistones,whileHDACsremovethem第4題WhereintheDNAmoleculedoescytosinemethylationoccur?AInthesugarphosphatebackboneoftheDNAmoleculeBInthenitrogenousbasesoftheDNAmoleculeCInthehistoneproteinsassociatedwiththeDNAmoleculeDInthephosphategroupsattachedtothehistoneproteinsProblems：IntroductionANDPrimarymessenger第1題The“l(fā)igand”presentsinthereceptor-ligandcomplexesinthissectionisreferredto()ALipidmoleculesincellmembranesBProteinmoleculesincellmembranesCprimarymessengerDsecondarymessenger第2題Extracellularsignalmoleculesarealsoknownas()AprimarymessengerBsecondarymessengerCthirdmessengerDnoneoftheabove第3題WhichofthefollowingisNOTacharacteristicofaprimarymessenger?AItbindstoareceptoronthecellsurfaceBItactivatesasignalingpathwayCItisusuallyaproteinorpeptideDItisproducedbythetargetcell第4題Whichofthefollowingisafunctionofareceptor?AToproduceaprimarymessengerBTotransmitasignalacrossasynapseCTobindtoaligandandinitiatearesponseDToregulategeneexpression第5題Whichofthefollowingistrueaboutparacrinesignaling?AItrequiresdirectcontactbetweencellsBItinvolvesthereleaseofsignalingmoleculesintothebloodstreamCItisslowerthanendocrinesignalingDItisfasterthanendocrinesignalingProblems：SecondMessengers第1題Whichoneofthefollowingisnotasecondmessenger?AcGMPBIP3CDAGDmRNA第2題Whichofthefollowingisafunctionofsecondmessengersinsignaltransduction?AAmplifythesignalBInitiategeneexpressionCActivateionchannelsDAlloftheabove第3題WhatistheroleofaGproteininthesecondmessengersignalingpathway?AItdirectlyactivatesenzymesinthecellBItbindstoandactivatesadenylatecyclaseCItbindstoandactivatesionchannelsDItamplifiesthesignalbyactivatingmultiplesecondmessengermolecules第4題WhichofthefollowingisanexampleofasecondmessengermoleculethatactivatesproteinkinaseA(PKA)?AcAMPBCalciumionsCGTPDAdenylatecyclase第5題WhatistheroleofaGs-coupledreceptor?AToactivateadenylatecyclaseandincreasecAMPlevelsBToactivateproteinkinaseA(PKA)CToactivatephospholipaseC(PLC)DToactivateionchannelsProblems：Gproteins第1題WhichofthefollowingisNOTatypeofGprotein?AGsBGiCGqDGr第2題WhenaGproteinisactivated,it:ABindsdirectlytoaneffectorproteinBReleasesGDPandbindsGTPCUndergoesphosphorylationbyakinaseDCleavesamembranelipidtoreleaseasecondmessenger第3題WhatisthemechanismofGproteinactivation?AThealphasubunitbindstoGTPanddissociatesfromthebetaandgammasubunits,activatingdownstreameffectorsBThealphasubunitbindstoGDPanddissociatesfromthebetaandgammasubunits,inhibitingdownstreameffectorsCThebetaandgammasubunitsbindtoGTPandactivatedownstreameffectorsDThebetaandgammasubunitsbindtoGDPandinhibitdownstreameffectors第4題WhichproteinfamilydoesRasbelongto?AGprotein-coupledreceptorsBTyrosinekinasesCSmallGTPasesDTranscriptionfactors第5題HowdosmallG-proteinsdifferfromGproteins?ASmallG-proteinsaresmallerinsizeBSmallG-proteinsarealwaysactiveCSmallG-proteinsarenotcoupledtoreceptorsDSmallG-proteinsareonlyfoundineukaryoticcellsProblems：Receptors第1題Whatistheroleofreceptorsinsignaltransduction?AReceptorsconvertextracellularsignalsintointracellularsignalsBReceptorsbindtoligandsandtransportthemacrossthecellmembraneCReceptorscatalyzechemicalreactionstoproduceintracellularsignalsDReceptorsregulategeneexpressioninresponsetoextracellularsignals第2題WhichofthefollowingisNOTafunctionofreceptors?ASensingenvironmentalstimuliBRegulatinggeneexpressionCTransmittingsignalsacrosscellsDCatalyzingchemicalreactions第3題WhichofthefollowingisnotacomponentoftheMAPKpathway?AMAPkinasekinasekinase(MAPKKK)BMAPkinasekinase(MAPKK)CMAPkinase(MAPK)DGprotein第4題Whatisthefunctionofionchannelreceptors?AToactivatesecondmessengerpathwaysBTobindtoligandsandactivateGproteinsCTotransportionsacrossthecellmembraneDToactivateenzymeactivity第5題Whichofthefollowingisnotasurfacereceptor?AIonchannelsreceptorBGProtein-CoupledReceptorCEnzyme-CoupledReceptorDRetinoicacid

receptorProblems：cAMP-PKApathway第1題WhatisthefirststepinthecAMP-PKApathway?AActivationofadenylylcyclaseBActivationofproteinkinaseACActivationofphosphodiesteraseDActivationofGprotein-coupledreceptors第2題WhatisthesecondmessengerinthecAMP-PKApathway?AGproteinBProteinkinaseACcAMPDAdenylylcyclase第3題WhatdoesCREBstandfor?ACyclicresponseelementbindingproteinBCyclicribosomalelementbindingproteinCCyclicregulatoryelementbindingproteinDCyclicAMPresponseelementbindingprotein第4題WhatisthestructureofCRE?AAproteinBAlipidCAcarbohydrateDADNAsequence第5題ThereceptorcoupledwithGproteinis?ACyclicreceptorBSeven-transmembranereceptorCIntracellularreceptorDNuclearreceptorECytoplasmicreceptorProblems：Insulinsignalpathway第1題Whatisthefunctionofaproteinphosphatase?AToaddphosphategroupstoproteinsBToremovephosphategroupsfromproteinsCToactivateenzymesDTodeactivateenzymes第2題Whatistheprimarystructureofinsulin?AAsinglepolypeptidechainBTwopolypeptidechainslinkedbydisulfidebondsCThreepolypeptidechainslinkedbydisulfidebondsDFourpolypeptidechainslinkedbydisulfidebonds第3題Whichofthefollowingisthecorrectorderofeventsininsulinreceptoractivation?AInsulinbinding→receptordimerization→autophosphorylation→insulinreceptorsubstrateactivationBReceptordimerization→autophosphorylation→insulinbinding→insulinreceptorsubstrateactivationCAutophosphorylation→insulinbinding→receptordimerization→insulinreceptorsubstrateactivationDInsulinbinding→autophosphorylation→receptordimerization→insulinreceptorsubstrateactivation第4題Whatisthenameofthedownstreamsignalingpathwaythatisactivatedbyinsulinreceptorsubstrate?API3K/AktpathwayBMAPK/ERKpathwayCJAK/STATpathwayDNF-κBpathway第5題Whatisasignalcascade?AAsequenceofchemicalreactionstriggeredbyasignalmoleculethatamplifiesandtransmitsthesignalwithinacellBAsequenceofphysicalinteractionsbetweenareceptorandaligandthatleadstoacellularresponseCAsequenceofgeneticmutationsthatresultinabnormalcellgrowthanddivisionDAsequenceofenzymaticreactionsthatbreakdownasignalmoleculeintoitscomponentpartsProblems：EGFsignalpathway第1題WhatisEGF?AAproteinkinaseBAsecondmessengerCAgrowthfactorDAtranscriptionfactor第2題HowdoesGrb2activateRas?ABydirectlybindingtoRasBByrecruitingtheSOSproteintotheplasmamembraneCByphosphorylatingRasDBydegradingRas第3題WhichdomainofGrb2isresponsibleforbindingtotheepidermalgrowthfactorreceptor(EGFR)?AS