生化變種試題及答案英文

Multiple-choiceQuestions(2pointseach,10questionsintotal)1.Whatisthemainfunctionofenzymesinbiochemicalreactions?A.ProvideenergyB.SpeedupreactionsC.StoreenergyD.TransportsubstancesAnswer:B2.Whichofthefollowingisamonosaccharide?A.SucroseB.GlucoseC.StarchD.CelluloseAnswer:B3.Thebasicunitofaproteinis_.A.NucleotideB.FattyacidC.AminoacidD.MonosaccharideAnswer:C4.DNAismainlylocatedin_.A.RibosomeB.MitochondriaC.NucleusD.CytoplasmAnswer:C5.WhatistheroleofATPincells?A.StorageofgeneticinformationB.CatalyzebiochemicalreactionsC.EnergycarrierD.ComponentofcellmembraneAnswer:C6.Whichvitaminisimportantforbloodclotting?A.VitaminAB.VitaminCC.VitaminDD.VitaminKAnswer:D7.Theprocessofconvertingglucosetopyruvateiscalled_.A.GlycolysisB.KrebscycleC.OxidativephosphorylationD.PhotosynthesisAnswer:A8.Themaincomponentofcellmembraneis_.A.ProteinB.LipidC.CarbohydrateD.NucleicacidAnswer:B9.Whichofthefollowingisaninorganicsubstance?A.ProteinB.WaterC.FatD.SugarAnswer:B10.Thefunctionofribosomeisto_.A.SynthesizeproteinsB.DigestsubstancesC.StoreenergyD.TransportmaterialsAnswer:AMultiple-choiceQuestions(2pointseach,10questionsintotal)1.Whichofthefollowingarepolysaccharides?(Selectallthatapply)A.GlycogenB.LactoseC.AmyloseD.ChitinAnswer:ACD2.Componentsofanucleotideinclude_.(Selectallthatapply)A.NitrogenousbaseB.PentosesugarC.PhosphategroupD.AminoacidAnswer:ABC3.Whichofthefollowingarefunctionsofproteins?(Selectallthatapply)A.CatalysisB.TransportationC.StructuresupportD.EnergystorageAnswer:ABC4.Whichfactorscanaffectenzymeactivity?(Selectallthatapply)A.TemperatureB.pHvalueC.SubstrateconcentrationD.EnzymeconcentrationAnswer:ABCD5.Whataretheproductsofglycolysis?(Selectallthatapply)A.PyruvateB.ATPC.NADHD.CO?Answer:ABC6.Whichofthefollowingarelipid-solublevitamins?(Selectallthatapply)A.VitaminAB.VitaminBC.VitaminDD.VitaminEAnswer:ACD7.Thecomponentsofcellmembraneinclude_.(Selectallthatapply)A.PhospholipidB.CholesterolC.ProteinD.CarbohydrateAnswer:ABCD8.WhichofthefollowingareinvolvedinDNAreplication?(Selectallthatapply)A.DNApolymeraseB.HelicaseC.PrimaseD.LigaseAnswer:ABCD9.Whichofthefollowingarefunctionsofthemitochondria?(Selectallthatapply)A.CellularrespirationB.ATPsynthesisC.ProteinsynthesisD.LipidsynthesisAnswer:AB10.WhichofthefollowingaretypesofRNA?(Selectallthatapply)A.mRNAB.tRNAC.rRNAD.DNAAnswer:ABCTrueorFalseQuestions(2pointseach,10questionsintotal)1.Allenzymesareproteins.(False)2.Glucoseisadisaccharide.(False)3.DNAandRNAhavethesamenitrogenousbases.(False)4.Thecellmembraneisastaticstructure.(False)5.Enzymescanchangetheequilibriumofabiochemicalreaction.(False)6.Mitochondriaarethepowerhousesofthecell.(True)7.Fatisthemainenergysourceforthebodyintheshortterm.(False)8.Transcriptionoccursinthecytoplasm.(False)9.AlllivingcellscontainDNA.(True)10.Theprimarystructureofaproteindeterminesitsfunction.(True)Short-answerQuestions(5pointseach,4questionsintotal)1.Describethestructureofanucleotidebriefly.Answer:Anucleotideconsistsofanitrogenousbase(adenine,guanine,cytosine,thymineinDNAoruracilinRNA),apentosesugar(deoxyriboseinDNAorriboseinRNA),andaphosphategroup.2.Explainthefunctionofenzymesinbiochemicalreactions.Answer:Enzymesarebiologicalcatalysts.Theylowertheactivationenergyofbiochemicalreactions,whichspeedsuptherateofreactionswithoutbeingconsumedintheprocess.3.WhatistheroleofATPincells?Answer:ATP(adenosinetriphosphate)isthemainenergycarrierincells.Itstoresandreleasesenergyforvariouscellularactivitieslikemusclecontraction,activetransport,andbiosynthesis.4.Brieflydescribetheprocessofglycolysis.Answer:Glycolysisisthefirststepofglucosecatabolism.Inthecytoplasm,glucoseisbrokendownintotwomoleculesofpyruvate,producingasmallamountofATPandNADHintheprocess.DiscussionQuestions(5pointseach,4questionsintotal)1.Discusstheimportanceofthecellmembraneinmaintainingcellfunction.Answer:Thecellmembraneactsasabarrier,separatingthecell'sinteriorfromtheexternalenvironment.Itcontrolstheentryandexitofsubstances,allowingnutrientsinandwasteout.Italsohasreceptorsforcellcommunicationandprovidesaplatformforsomebiochemicalreactions,thusmaintainingcellhomeostasis.2.ExplaintherelationshipbetweenDNA,RNA,andproteinsynthesis.Answer:DNAstoresgeneticinformation.Throughtranscription,DNAisusedtosynthesizeRNA.Then,duringtranslation,RNA(mRNA,tRNA,rRNA)worktogethertoassembleaminoacidsintoproteinsaccordingtothegeneticcodecarriedbymRNA.3.Discusshowchangesintemperaturecanaffectenzymeactivity.Answer:Enzymeactivityishighlytemperature-dependent.Atlowtemperatures,enzymeactivityislowasmolecularmotionisslow.Astemperaturerises,activityincreasesuntilitreachesanoptimaltemperature.Beyondthispoint,hightemperaturescandenaturetheenzyme(changeitsstructure),causingarapiddecreaseinactivity.4.Describethesignificanceofbiochemicalpathwaysincells.Answer:Biochemic