2026年托福听力学术讲座生物类专项卷：生物化学与药物设计的试题

2026年托福听力学术讲座生物类专项卷：生物化学与药物设计的试题考试时间：______分钟总分：______分姓名：______Section1(1)ProfessorChenisdiscussingthemechanismsbywhichcertainenzymesregulatemetabolicpathways.ShementionsthatanenzymecalledPhosphofructokinase-1(PFK-1)isakeyregulatorypointinglycolysis.WhenthecellhashighlevelsofATP,PFK-1activityisinhibited.Thishelpspreventtheunnecessarybreakdownofglucosewhenenergyisalreadyabundant.Conversely,whenATPlevelsarelow,anallostericregulatorbindstoPFK-1,activatingitandthuspromotingglycolysistogeneratemoreATP.ProfessorChenalsonotesthatthisregulationiscrucialformaintainingenergyhomeostasisinthecell.Questions:1.Accordingtotheprofessor,whathappenstoPFK-1activitywhenthecellhashighlevelsofATP?2.Whatistheroleoftheallostericregulatormentionedinthelecture?3.Accordingtotheprofessor,whyistheregulationofPFK-1importantforthecell?(2)Aresearcherisdiscussingherworkondevelopinganewdrugtotreataspecificgeneticdisorder.Thedisorderiscausedbyamutationthatleadstotheproductionofanon-functionalenzymeneededforacrucialmetabolicstep.Theresearchermentionsthatherteamisusingcomputationalmethodstodesigndrugmoleculesthatcanbindtotheactivesiteofthemutatedenzyme,effectivelycompensatingforitsdysfunction.Sheexplainsthattheyarefocusingondesigningmoleculesthatcanstabilizetheenzyme'sactiveconformationorblockthesubstratefrombindingtothemutationsite.Thegoalistorestoretheenzyme'sfunctionandalleviatethesymptomsofthedisorder.Shealsomentionsthatsolubilityandmetabolicstabilityareimportantpropertiesforthedrugcandidatetohaveforgoodbioavailability.Questions:1.Whatproblemdoesthegeneticdisorderdiscussedinthelecturecause?2.Whatisthemainapproachtheresearcheristakingtodevelopthenewdrug?3.Accordingtotheresearcher,whataretwoimportantpropertiesforthedrugcandidatetohave?(3)InalectureonDNArepairmechanisms,theprofessordiscussesaprocesscallednucleotideexcisionrepair(NER).SheexplainsthatNERisresponsibleforremovingdamagecausedbyUVradiation,suchasthyminedimers.Theprofessordescribestheprocessasinvolvingseveralsteps.First,aproteincomplexscanstheDNAfordamage.Onceadimerisdetected,theDNAisunwound,anda"切口"(nick)ismadeonbothstrandsnearthedamagesitebyspecificendonucleases.Then,asegmentofthedamagedstrand,includingthedimer,isremoved.Finally,DNApolymerasefillsinthegapusingtheundamagedstrandasatemplate,andDNAligasesealsthenewlysynthesizedDNAbackbone.TheprofessoremphasizesthatNERisessentialforpreventingmutationsandmaintaininggenomicintegrity.Questions:1.Accordingtotheprofessor,whatkindofDNAdamagedoestheNERpathwayprimarilyrepair?2.WhatarethetwoenzymesmentionedbytheprofessorthatmakecutsintheDNAstrandsnearthedamagesite?3.Accordingtotheprofessor,whatensurestheaccuracyoftherepairedDNA?(4)ProfessorLeeistalkingaboutsignaltransductionpathways.Hestartsbyexplainingthatthesepathwaysallowcellstorespondtoexternalsignals.Hegivestheexampleofahormonebindingtoareceptoronthecellsurface.Thisbindingeventtriggersaseriesofbiochemicalreactionsinsidethecell,ofteninvolvingtheactivationofproteinkinases,whichthenphosphorylateotherproteins.ProfessorLeenotesthatonecommontypeofsecondmessengeriscyclicAMP(cAMP),whichcanactivateProteinKinaseA(PKA).Onceactivated,PKAcangoontomodifymanydifferenttargetproteins,leadingtoawiderangeofcellularresponses,suchaschangesingeneexpressionorenzymeactivity.Heconcludesbysayingthatunderstandingthesepathwaysiscrucialfordevelopingdrugsthatcantargetspecificdiseasesbymodulatingcellularresponses.Questions:1.AccordingtoProfessorLee,whatinitiatesasignaltransductionpathway?2.WhatismentionedasacommonsecondmessengerthatcanactivateProteinKinaseA?3.AccordingtoProfessorLee,whatisonepossibleoutcomeofProteinKinaseAbeingactivated?Section2(1)Inadiscussionaboutdrugdevelopment,aninstructornotesthatachievingdrug-targetresidencetime(DTRT)isacriticalfactorforcertaintherapies.ShortDTRTmightmeanthedrugdoesn'tstaylongenoughtoeffectivelyinteractwithitstargetandexertitsdesiredeffect.Theinstructorgivestheexampleofantiviraldrugs,whereprolongedbindingtoviralenzymescouldprovideamoresustainedtherapeuticwindow.ShementionsthatdrugdesignerssometimesintentionallymodifydrugmoleculestoincreasetheirDTRT,perhapsbymakingthemlesssusceptibletometabolicbreakdownorbyenhancingtheirbindingaffinity.However,shecautionsthatexcessivelylongDTRTcanalsoleadtooff-targeteffectsortoxicity,sofindingtherightbalanceiskey.Questions:1.Accordingtotheinstructor,whatcouldbeadisadvantageofshortdrug-targetresidencetime?2.WhatstrategymightdrugdesignersusetoincreaseDTRT?3.Accordingtotheinstructor,whyisachievinganoptimalDTRTimportant?(2)Astudentispresentingresearchonthestructure-activityrelationships(SAR)ofaseriesofkinaseinhibitors.Shebeginsbyshowingatableofdata,whichsheexplainscomparesthepotencyofdifferentinhibitorsagainstaspecifickinase.ThestudentnotesthattheleadcompoundhadacertainIC50value.Shethendescribeshowherteamsystematicallymodifiedthecompound'sstructurebyaddingorchangingfunctionalgroups.Forinstance,replacingahydrogenatomwithamethylgroupincreasedthepotencybyabout10-fold.However,addingahydroxylgroupatadifferentpositionresultedinsignificantlyreducedactivity.SheconcludesthatunderstandingSARallowsresearcherstooptimizeinhibitorsforbetterselectivityandefficacy.Questions:1.Whatdidthestudent'sresearchfocusoninvestigating?2.Accordingtothestudent,whatmodificationtotheleadcompoundresultedinincreasedpotency?3.Whatwasthemainconclusiondrawnfromthestudent'sexperiments?(3)Alecturecoverstheconceptofmetabolicfluxanalysis.Thespeakerexplainsthatit'satechniqueusedtomeasuretherateofmetabolicreactionswithinacell.Theprimarygoalistounderstandhowmuchofthesubstratesarebeingconvertedintoproductsandhowdifferentpathwaysareinterconnected.Thespeakermentionsthatmethodslikestableisotopelabelingareoftenused.Byintroducingastableisotope,suchas13C,intospecificmolecules,researcherscantrackitsmovementthroughthemetabolicnetwork.Analyzingthedistributionoflabeledcompoundsovertimeprovidesinformationabouttherelativeratesofdifferentreactions.Thespeakeremphasizesthatthisinformationisvaluableformetabolicengineering,allowingscientiststomanipulatepathwaysforbiotechnologicalapplications,suchasproducingbiofuelsorpharmaceuticals.Questions:1.Accordingtothespeaker,whatisthemainobjectiveofmetabolicfluxanalysis?2.Whattechniqueinvolvingstableisotopesismentionedasamethodforconductingmetabolicfluxanalysis?3.Accordingtothespeaker,whatpotentialapplicationofmetabolicfluxanalysisismentioned?(4)Aresearcherisdescribinganexperimentdesignedtostudytheeffectsofadrugcandidateonproteinfolding.Shementionsthatmisfoldedproteinscanaggregateandcausevariousdiseases,suchasAlzheimer's.Herteamisusingafluorescentdyethatbindsspecificallytomisfoldedregionsofproteins.Theyincubatedcellswiththeirdrugcandidateandthenmeasuredthefluorescencesignal.Theresearcherreportsthatthedrugcandidatesignificantlyreducedthefluorescencesignalcomparedtoacontrolgroup,suggestingthatitpromotedcorrectproteinfoldingorpreventedmisfolding.Shenotesthatthisisanearlyindicationthatthedrugmighthavetherapeuticpotentialforrelateddiseases,butfurtherstudiesareneededtoconfirmitsmechanismofactionandefficacy.Questions:1.Accordingtotheresearcher,whatproblemdomisfoldedproteinscause?2.Whatexperimentalobservationdidtheresearcherreportaftertreatingcellswiththedrugcandidate?3.Accordingtotheresearcher,whatdoesthereducedfluorescencesignalsuggestaboutthedrugcandidate'seffectonproteinfolding?试卷答案(1)1.Itisinhibited.(解析：讲座提到"WhenthecellhashighlevelsofATP,PFK-1activityisinhibited.")2.ItactivatesPFK-1whenATPlevelsarelow.(解析：讲座提到"whenATPlevelsarelow,anallostericregulatorbindstoPFK-1,activatingit...")3.Ithelpsmaintainenergyhomeostasisinthecell.(解析：讲座结尾提到"thisregulationiscrucialformaintainingenergyhomeostasisinthecell.")(2)1.Itcausestheproductionofanon-functionalenzymeneededforacrucialmetabolicstep.(解析：讲座提到"Thedisorderiscausedbyamutationthatleadstotheproductionofanon-functionalenzymeneededforacrucialmetabolicstep.")2.Usingcomputationalmethodstodesigndrugmoleculesthatcanbindtotheactivesiteofthemutatedenzyme.(解析：讲座提到"herteamisusingcomputationalmethodstodesigndrugmoleculesthatcanbindtotheactivesiteofthemutatedenzyme...")3.Solubilityandmetabolicstability.(解析：讲座提到"Thegoalistorestoretheenzyme'sfunctionandalleviatethesymptomsofthedisorder.Shealsomentionsthatsolubilityandmetabolicstabilityareimportantpropertiesforthedrugcandidatetohaveforgoodbioavailability.")(3)1.Thyminedimers.(解析：讲座提到"NERisresponsibleforremovingdamagecausedbyUVradiation,suchasthyminedimers.")2.Specificendonucleases.(解析：讲座提到"Onceadimerisdetected,theDNAisunwound,anda'切口'(nick)ismadeonbothstrandsnearthedamagesitebyspecificendonucleases.")3.DNApolymeraseusestheundamagedstrandasatemplate.(解析：讲座提到"Then,DNApolymerasefillsinthegapusingtheundamagedstrandasatemplate...")(4)1.Ahormonebindingtoareceptoronthecellsurface.(解析：讲座提到"Hegivestheexampleofahormonebindingtoareceptoronthecellsurface.Thisbindingeventtriggersaseriesofbiochemicalreactionsinsidethecell...")2.CyclicAMP(cAMP).(解析：讲座提到"ofteninvolvingtheactivationofproteinkinases,whichthenphosphorylateotherproteins.ProfessorLeenotesthatonecommontypeofsecondmessengeriscyclicAMP(cAMP)...")3.Changesingeneexpressionorenzymeactivity.(解析：讲座提到"Onceactivated,PKAcangoontomodifymanydifferenttargetproteins,leadingtoawiderangeofcellularresponses,suchaschangesingeneexpressionorenzymeactivity.")Section2(1)1.Itmightnotstaylongenoughtoeffectivelyinteractwithitstargetandexertitsdesiredeffect.(解析：讲座提到"ShortDTRTmightmeanthedrugdoesn'tstaylongenoughtoeffectivelyinteractwithitstargetandexertitsdesiredeffect.")2.Makingthemlesssusceptibletometabolicbreakdownorenhancingtheirbindingaffinity.(解析：讲座提到"drugdesignerssometimesintentionallymodifydrugmoleculestoincreasetheirDTRT,perhapsbymakingthemlesssusceptibletometabolicbreakdownorbyenhancingtheirbindingaffinity.")3.Findingtherightbalanceiskey.(解析：讲座最后提到"sofindingtherightbalanceiskey.")(2)1.Thestructure-activityrelationships(SAR)ofaseriesofkinaseinhibitors.(解析：讲座开头提到"Astudentispresentingresearchonthestructure-activityrelationships(SAR)ofaseriesofkinaseinhibitors.")2.Replacingahydrogenatomwithamethylgroup.(解析：讲座提到"replacingahydrogenatomwithamethylgroupincreasedthepotencybyabout10-fold.")3.UnderstandingSARallowsresearcherstooptimizeinhibitorsforbetterselectivityandefficacy.(解析：讲座结尾提到"SheconcludesthatunderstandingSARallowsresearcherstooptimizeinhibitorsforbetterselectivityandefficacy.")(3)1.Tounderstandhowmuchofthesubstratesarebeingconvertedintoproductsandhowdifferentpathwaysareinterconnected.(解析：讲座提到"Theprimarygoalistounderstandhowmuchofthesubstratesarebeingconvertedintoproductsandhowdifferentpathwaysareinterconnected.")2.Stableisotopelabeling.(解析：讲座提到"Byintroducingastableisotope,suchas13C,into