英语_专科起点本科4套卷试卷

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1、大学英语A一.阅读理解（共20题,共40分）1.Despitethefactthattodayviruses(病毒)areknowntocausecancerinanimalsandincertainplants,thereexistsagreatreluctancetoacceptvirusesasbeingofimportanceinhumancancer.Basicbiologicalphenomenagenerallydonotdifferstrikinglyasonegoesfromonespeciestoa

2、nother.Itshouldberecognizedthatcancerisabiologicalproblemandnotaproblemthatisuniquetoman.Canceroriginateswhenanormalcellsuddenlybecomesacancercellwhichmultiplieswidelyandwithoutapparentrestraint.Cancermayoriginateinmanydifferentkindsofcell,butthecancercellusuall

3、ycontinuestocarrycertaintraits(特性)ofthecelloforigin.Thetransformationofanormalcellintoacancercellmayhavemorethanonekindofcause,butthereisgoodreasontoconsidertherelationshipsthatexistbetweenvirusesandcancer.Sincethereisnoevidencethathumancancer,asgenerallyexperie

4、nced,isinfectious,manypersonsbelievethatbecausevirusesareinfectiousagentstheycannotpossiblybeofimportanceinhumancancer.However,virusescanmutate(突变)andexamplesareknowninwhichavirusthatneverkillsitshostcanmutatetoformanewstrainofvirusthatalwayskillsitshost.Itdoesn

5、otseemunreasonabletoassumethataharmlesslatentvirusmightmutatetoformastrainthatcausescancer.Certainlytheexperimentalevidencenowavailableisconsistentwiththeideathatvirusesasweknowthemtodaycouldbethecausative(引起…的)agentsofmost,ifnotallcancer,includingcancerinman.（1

6、0分）（答题时限：00:01:00）(1)Accordingtothepassage,cancercellsare____.（2分）（答题时限：00:00:30）A.similartothecelloforiginB.mutationsofvirusesC.unabletoreproduceD.amongthesmallestcellknown★检查答案标准答案：A(2)Thebesttitleforthispassageis____.（2分）（答题时限：00:00:30）A.NewLightontheCausesof

7、CancerB.TheNewestTheoryontheNatureofVirusesC.VirusesandcancerD.OntheNatureofLife★检查答案标准答案：C(3)Cancershouldbeconsideredtobeabiologicalproblemratherthanamedicalonebecause____.（2分）（答题时限：00:00:30）A.virusesareknowntocausecancerinanimalsB.atpresent,humancancerisnotbel

8、ievedtobeinfectiousC.therearemanyknowncausesforthetransformationofanormalcelltoacancercellD.resultsofexperimentsonplantsandanimalsdonotvarygreatlyfromspeciestospecies