科学家从皮肤细胞中培育出人类卵细胞-生物科学技术（阅读理解专练）（解析版）

科学家从皮肤细胞中培育出人类卵细胞（解析版）目录时文精读------------------------------------------------------------精选外刊阅读理解【阅读理解】【课标词汇积累】【课标词汇训练】【参考译文】好题精练----------------------------------------------------------精选名校及联考话题专练【阅读理解】【阅读7选5】【完形填空】【语法填空】时文精读时文精读读【话题·导语】科学家从皮肤细胞中培育出人类卵细胞。【原文·时文阅读】文章来源：https:///article/human-egg-cells-from-skin-cellsAtechniqueusedincloningcombinedwithfertilizationandabitofchemicalcoaxingcausedhumanskincellstoproduceeggsabletogiverisetoearlyhumanembryos,researchersreportSeptember30inNatureCommunications.Theeffortisthelatestattempttomakeeggsandspermfromhumancells.Researchershavealreadysucceededinmakingtheseimportantcelltypesfrommanytypesofanimals,includingpandas.Butproducinghumaneggsandspermhasprovenelusive.Suchtechnologymayonedaytreatinfertilityforwomenwhonolongerhaveeggsbecauseofage,earlymenopauseorpreviouscancertreatments.Same-sexmalecouplesmayalsobeabletousethetechnique“tohave,potentially,achildthat’sgeneticallyrelatedtobothpartners,”saysreproductiveendocrinologistPaulaAmatoofOregonHealth&ScienceUniversityinPortland.Fornow,thetechnique“istooinefficientandhighrisktoapplyimmediatelytoclinicalapplication,”saysstemcellresearcherKatsuhikoHayashioftheUniversityofOsakainJapan.Hayashiwasnotinvolvedwiththiseffortbutpreviouslyreprogrammedtailcellsfromtwoadultmalemiceintoeggsandsperm.Thosereprogrammedcellsgaverisetohealthymicethathadtwobiologicalfathersandwereabletohaveoffspringoftheirown.Aversionofthenewtechniquealsoworksinmice,Amatosays.“Usually,thingsthatwecangettoworkinmiceeventuallyworkinhumans.”Atleast,inmakingstemcellsitdoes.Amatoandcolleaguesremovedthenucleus（细胞核）fromahumaneggcellandreplaceditwiththenucleusofatypeofskincellcalledafibroblast（细胞核移植技术）.Thatstep,calledsomaticcellnucleartransfer,isthesamefirststepusedincloningDollytheSheepandmanyotherspecies.Buttheresearchersweren’ttryingtomakeahumanclone.Theywantedtomakeaneggcell,whichhas23chromosomes（染色体）.That’shalfthenumberofchromosomesasmostothercellsinthebody,whichcarryasetof23chromosomesinheritedfromthemotherand23fromthefather.Cellsthatwillgiverisetoeggsandspermgothroughatypeofcelldivisioncalledmeiosis（减数分裂）,whichhalvesthenumberofchromosomes.Inthatprocess,eachchromosomepairswithitscounterpartfromtheotherparentandswapssomeDNA.Thecellthendivides,pullingonehalfofeachpairintodaughtercells.Then,wheneggsandspermgettogether,theyproduceazygote（受精卵）with46chromosomesthatwilldivideandmakeeverycellinthebody.Buttheclonedeggalreadyhad46chromosomes.Withmice,Amatoandcolleaguesjustfertilizedtheclonedeggwithsperm.Thatcausedtheeggtojettisonhalfitschromosomes,producinganembryowiththecorrectnumberofchromosomes.Thehumaneggs,though,didn’textrudehalftheirchromosomeswhenfertilized.Sotheresearchershadtoaddchemicalpersuasionintheformofamoleculecalledroscovitine.Thatmoleculeallowedthewinnowingofchromosomestobegin.Someofthefertilizedeggsmadeearlyhumanembryos,butmanydidnot.“That’sprobably,wethink,becausetheyhadanabnormalnumberofchromosomes,”Amatosays.Thesefailedwould-beeggskickedouthalftheirchromosomes,onaverage,butnottherighthalf.Noneoftheembryoswereallowedtodevelopbeyondtheblastocyst（胚囊）stage,growingforaboutsixdays.Manystoppeddevelopingatearlierstages.Noneoftheembryosendedupwiththecorrectsetsofchromosomessoultimatelywerenotviable.Forinstance,oneembryohad48chromosomesinsteadof46.Thatembryohadall23chromosomesfromthesperm,butamishmashof25chromosomesfromtheskincell.Somechromosomeswerepresentinasinglecopy,whileothershadtwocopies,andotherchromosomesweremissingentirely.Theunequaldivisionsprobablyresultedbecausethechromosomespairedrandomlyinsteadofwiththeirspecificmateastheywouldinnormalmeiosis,Amatosays.“Itwasnottheoutcomewewanted,really,butitwasmoreproof-of-concept.‘Hey,wecankindofmakethisprocesshappennow,’”Amatosays.Theteamisworkingtogetthechromosomestodivvyupproperlybutsheestimatesatleastadecadebeforethetechniquecouldbetestedinclinicaltrials.Eventhen,suchtrialswouldprobablynottakeplaceintheUnitedStates,whichprohibitsgeneticmodificationofhumanembryos,shesays.Thenewtechniquehasadrawbackinthatitrequiresdonoreggcellsforthecloningstep,Hayashisays.Reprogrammingasheandcolleagueshavedonedoesnotneedeggcellstomakeothereggcells.Still,hesays,“thistechnologyhasmadeasignificantbreakthroughinhalvingthehumangenome.”Hepredicts“newtechnologieswillstemfromthisachievement.”【原创·阅读理解】1.Whatdoestheunderlinedwordinthesecondparagraphmean?A.difficulttofindB.successfultosolveC.failtodoD.easytomakeA词义猜测题。根据文章第二段中的Researchershavealreadysucceededinmakingtheseimportantcelltypesfrommanytypesofanimals,includingpandas.But研究人员已成功从多种动物（包括大熊猫）中培育出这些重要细胞类型。但是……，根据句中的but可知，后面的事情，应该是难以做到的，完成是有困难的。故选A。2.WhatwasthepossiblereasonwhydidAmato’sexperimentfail?A.BecausetheAmericangovernmentdidn’tsupporttheresearch.B.Becausethefertilizedeggshadanabnormalnumberofchromosomes.C.Becausehisteamdidn’tcollectenoughmoneyfortheexperiment.D.Becausehisteamdidn’thavetheorytosupporttheexperiment.B考查细节理解题。根据文章中的Someofthefertilizedeggsmadeearlyhumanembryos,butmanydidnot.“That’sprobably,wethink,becausetheyhadanabnormalnumberofchromosomes,”Amatosays.部分受精卵发育为早期人类胚胎，但多数未能成功。“我们认为这很可能源于染色体数目异常，”阿马托解释道。故选B。3.Whichiscorrectaccordingtotext?A.Hayashithinksthatthenewtechniqueisuseless.B.Makingeggcellsfromskincellsfrommanytypesofanimalsissuccessful.C.HayashiisamemberoftheAmato’sexperiment.D.Amatopredictstenyearsbeforethetechniquecouldbetestedinclinicaltrials.B细节理解题。根据文章第二段中的Theeffortisthelatestattempttomakeeggsandspermfromhumancells.Researchershavealreadysucceededinmakingtheseimportantcelltypesfrommanytypesofanimals,includingpandas.这项研究是利用人类细胞制造卵子和精子的最新尝试。研究人员已经成功地从包括大熊猫在内的多种动物中制造出这些重要的细胞类型。故选B。4.WhatisAmato’sattitudetothetechnique?A.confidentB.skepticalC.negativeD.indifferentA考查推理判断题。根据文章中的“Itwasnottheoutcomewewanted,really,butitwasmoreproof-of-concept.‘Hey,wecankindofmakethisprocesshappennow,’”Amatosays.Theteamisworkingtogetthechromosomestodivvyupproperlybutsheestimatesatleastadecadebeforethetechniquecouldbetestedinclinicaltrials."虽未达预期目标，但验证了技术可行性，"阿马托表示。团队正着力解决染色体精准分配难题，预计至少需十年才可能开展临床试验。可知，Amato对这个科学实验是有信心的。故选A。【课标词汇积累】1.techniquen.技术,技能Theteacherdemonstratedanewmemorizationtechniquebyusingcolorfulmindmapstohelpstudentsrememberhistoricaleventsmoreeffectively.

老师展示了一种新的记忆技巧，通过使用彩色思维导图帮助学生更有效地记住历史事件。2.combinev.使结合，混合,联合,（使）联合；（使）合并n.联盟，集团Thescienceprojectrequiredustocombinedifferentchemicalstoobservethereactions,whichwasbothexcitingandeducational.科学项目要求我们将不同的化学物质混合以观察反应，这既有趣又有教育意义。3.previouslyadv.事先,以前,仓促Previously,ourschoollibraryonlyhadafewoutdatedbooks,butnowit'sfilledwithnewnovelsandreferencematerials.以前，我们学校图书馆只有几本过时的书，但现在堆满了新小说和参考资料。4.attemptv.努力，尝试，企图n.努力，尝试，（杀人）企图Ourclasswillattempttoorganizeacharitybakesaletoraisefundsforthelocalanimalshelter.我们班将尝试组织一场慈善烘焙义卖，为当地动物收容所筹集资金。5.potentiallyadv.潜在地；可能地Stayinguplatetoplayvideogamescanpotentiallyaffectyourconcentrationinclassthenextday.

熬夜玩电子游戏可能会影响你第二天的课堂注意力。6.reprogrammev.再次（重新）设定程序Afterfailingthemidterm,Idecidedtoreprogrammemystudyhabitsbycreatingastrictscheduleandstickingtoit.期中考试不及格后，我决定重新调整学习习惯，制定严格的时间表并坚持执行。7.modificationn.修改，修正，变更，改良，改进Theschoolcafeteriamadeahealthymodificationtoitsmenubyreplacingfriedfoodswithgrilledoptions.

学校食堂对菜单做了健康调整，用烤制食品替代了油炸食品。8.randomlyadv.随便地，未加计划地Theprincipalwouldrandomlyvisitclassroomstocheckifstudentswerefocusedduringlessons.校长会随机抽查教室，看学生上课是否专注。9.abnormaladj.不正常的，异常的；畸形的Itwasabnormalfortheusuallypunctualstudenttobelatethreedaysinarow,sotheteacheraskedifeverythingwasokay.一向守时的学生连续三天迟到很不寻常，所以老师询问是否一切正常。10.persuasionn.劝说，说服（力）；信仰Thestudentcouncilusedcreativepersuasiontacticslikefreesnackstoencouragemorestudentstoattendtheafter-schoollecture.学生会用免费零食等创意劝说策略鼓励更多学生参加课后讲座。【课标词汇训练】根据语境，从上面的“课标词汇”中选用合适的单词及其正确形式将句子补充完整。1.Thebasketballcoachtaughtusaspecialshooting_____________thatimprovedouraccuracyduringpractice.篮球教练教了我们一种特殊的投篮技巧，在训练中提高了我们的命中率。2.Wedecided_____________ourideasfortheschoolfestivalandcreateauniqueperformancethatincludedbothdanceanddrama.我们决定将校园节的想法结合起来，创作一个包含舞蹈和戏剧的独特表演。3.Ihad_____________struggledwithmath,butafterextratutoringsessions,mygradesimprovedsignificantly.我之前数学很差，但在额外辅导课后，成绩显著提高了。4.Duringthesportsmeet,Johnmadeabrave_____________tobreaktheschool'slongjumprecord,landingjustafewcentimetersshort.运动会上，约翰勇敢尝试打破学校的跳远纪录，只差几厘米就成功了。5.Joiningthedebateclubcould_____________helpshystudentsbuildconfidenceinpublicspeaking.参加辩论社可能帮助害羞的学生建立公开演讲的信心。6.Thecomputerteachershowedushow_____________therobottocompleteanobstaclecourseinsteadofjustmovinginstraightlines.计算机老师教我们如何重新编程机器人，让它完成障碍路线而不仅是直线移动。7.OurEnglishteachersuggestedsome_____________toouressayoutlinestomakeourargumentsclearer.英语老师对我们的作文提纲提出了一些修改建议，使论点更清晰。8.Forthegroupproject,ourteacher_____________assignedteammatestoensureeveryoneworkedwithdifferentclassmates.分组作业时，老师随机分配组员以确保每个人和不同的同学合作。9.The_____________heatwaveinOctoberforcedourschooltocanceloutdoorPEclassesforsafetyreasons.十月的异常热浪迫使学校出于安全取消户外体育课。10.Aftermuch_____________fromtheartteacher,theshystudentfinallyagreedtodisplayherpaintingsintheschoolexhibition.经过美术老师的多次劝说，害羞的学生终于同意在学校展览中展示她的画作。Keys:1.technique2.tocombine3.previously4.attempt5.potentially6.toreprogramme7.modifications8.randomly9.abnormal10.persuasion【参考译文】研究人员在9月30日的《自然-通讯》中报告称，通过结合克隆技术与体外受精，并辅以化学诱导手段，成功使人类皮肤细胞产生能够发育为早期人类胚胎的卵细胞。该研究是人类细胞制造卵子和精子技术的最新突破。此前科学家已从包括大熊猫在内的多种动物细胞中培育出配子，但人类配子的制备始终面临挑战。这项技术未来或可帮助因年龄、早发性绝经或癌症治疗而卵子枯竭的女性解决不孕问题。"同性男性伴侣也可能通过该技术获得与双方均有遗传关联的后代，"波特兰俄勒冈健康与科学大学的生殖内分泌学家保拉·阿马托表示。但大阪大学干细胞研究者林克彦指出，当前技术"效率过低且风险过高，无法立即投入临床应用"。林克彦虽未参与本研究，但曾将成年雄性小鼠尾部细胞重编程为卵子和精子，并成功培育出拥有双父系基因的健康小鼠后代。阿马托说，这种新技术的一个版本也适用于老鼠。“通常，我们能在老鼠身上起作用的东西最终会在人类身上起作用。”至少在制造干细胞的过程中是这样的。阿马托团队采用体细胞核移植技术——即克隆多利羊的技术路径——将皮肤成纤维细胞的细胞核植入去核人类卵细胞。与克隆不同，研究者旨在制造仅含23条染色体的卵细胞。正常配子形成需经历减数分裂，使染色体数量减半并完成基因重组。但克隆卵细胞初始携带46条染色体，小鼠实验中直接受精即可触发染色体减半，而人类卵细胞需依赖化学药物罗可维汀诱导。实验显示，部分受精卵可发育至囊胚阶段（约6天），但因染色体分配异常均未存活。典型失败案例中，一个胚胎含有精子提供的完整23条染色体，却混杂了皮肤细胞来源的25条染色体，呈现单拷贝、双拷贝甚至完全缺失的混乱状态。阿马托解释，这种异常源于染色体随机配对而非正常减数分裂的特异性配对。"虽未达预期目标，但验证了技术可行性，"阿马托表示。团队正着力解决染色体精准分配难题，预计至少需十年才可能开展临床试验。鉴于美国禁止人类胚胎基因编辑，相关试验或将在其他地区进行。林克彦指出该技术仍需捐赠卵细胞作为核移植载体，不如其团队开发的直接重编程方案便捷。但他承认："这项研究在人类基因组减半技术上取得重大突破，必将催生更多衍生技术。"好题精练好题精练练Passage1阅读理解KnownforitsroleinGameofThrones(《权力的游戏》),thedirewolf(冰原狼)wentextinctover10,000yearsago.OnApril7,theUScompanyColossalBiosciencesannouncedrestoringthisspeciesviade-extinction—ahistoricfirst.Timemagazinesaidscientistsstudiedfossils(化石)suchasa13,000-year-olddirewolftoothanda72,000-year-oldearboneandcomparedtheirgenestothoseofgraywolvestodiscoverdifferences.Theyedited14keygenesingraywolfbloodcellstomatchdirewolftraits,implantingmodifiedcell’snuclei(核)intosurrogate(代孕)dogs’eggs.Thebabies,largerthangraywolves,nowliveinapreserve.Theybehavedlikewolvesbyhowlingattwoweeksold.But“wehavenotseenthemattempttohuntliveprey”,Colossal’sPaigeMcNickletoldTimemagazine.Somescientistshavecriticizedtheproject.ProfessorNicRawlencefromOtagoUniversityquestionedusingfossilDNA,callingittoodamagedtouse.“AncientDNAislikeifyouputfreshDNAina500degreeovenovernight,itcomesoutlikedust,”RawlencetoldtheBBC．HearguedColossalactuallyonlycreated“ahybrid(杂交品种)”—agraywolfwithdirewolffeatures.Colossalisn’tjustrevivingthedirewolf.Theirlistincludesthewoollymammoth,dodoandTasmaniantiger.Theirmissiongoesbeyondde-extinction:theyalsousethesametechniquetopreventspeciesindangerfromdisappearing.Forexample,theybroughtbackfourredwolves,anendangeredspecies,inthesamewayofrestoringthedirewolf.TheCenterforBiologicalDiversitypredictsthat30%oftheplanet’sgeneticdiversitycouldbelostby2050.ColossalCEOBenLammarguesthatgeneticengineeringiscrucialtopreventthisloss.Yetsomewarntherecouldbeconsequences.Introducingnewspeciescancauseinvasivespecies,whilecloningoftenleadstohealthproblemsinanimalsandsurrogates.1．Howdidscientiststrytorestorethedirewolves?A．ByobtainingDNAfromlivingdirewolves.B．Byhybridizingdifferentmodernwolfspecies.C．Bystudyingfossilsofdirewolfandsurrogating.D．ByusingcompleteDNAofdirewolvestoclone.2．Whatcanbelearnedaboutthe“restored”direwolfbabies?A．Theyexhibitsomewolf-likebehaviors.B．Theyhavealreadybegunhuntingliveprey.C．Theyarebiggerinsizethanadultgraywolves.D．Theyarecompletelythesameastheancientdirewolves.3．Whydoestheauthormentionredwolvesinthe5thparagraph?A．Toillustratethevarietyofrevivedspecies.B．Tohighlighttheimportanceofbiodiversity.C．Tocontrastwiththedirewolf’srevivalprocess.D．ToshowColossal’sbroaderconservationefforts.4．Whatistheauthor’sattitudetowardsthede-extinction?A．Opposedandcritical. B．Objectiveandcautious.C．Supportiveandoptimistic. D．Humorousandunconcerned.【答案】1．C2．A3．D4．B【解析】本文是一篇新闻报道。文章主要报道了美国公司ColossalBiosciences通过基因编辑技术尝试复活已灭绝的冰原狼，以及该技术面临的争议和更广泛的应用。1．细节理解题。根据第二段中“Timemagazinesaidscientistsstudiedfossils(化石)suchasa13,000-year-olddirewolftoothanda72,000-year-oldearboneandcomparedtheirgenestothoseofgraywolvestodiscoverdifferences.Theyedited14keygenesingraywolfbloodcellstomatchdirewolftraits,implantingmodifiedcell’snucleiintosurrogatedogs’eggs.(据《时代》杂志报道，科学家们研究了化石，比如一颗1.3万年前的冰原狼牙齿和一块7.2万年前的耳骨，并将它们的基因与灰狼的基因进行比较，以发现差异。他们编辑了灰狼血细胞中的14个关键基因，使其与冰原狼的特征相匹配，将修改后的细胞核植入代孕狗的卵子中)”可知，科学家们是通过研究冰原狼的化石，编辑灰狼血细胞中的关键基因，并将其植入代孕狗的卵子中，来尝试恢复冰原狼的。故选C。2．细节理解题。根据第三段中“Thebabies,largerthangraywolves,nowliveinapreserve.Theybehavedlikewolvesbyhowlingattwoweeksold.(这些幼崽比灰狼大，现在生活在一个保护区里。它们在两周大的时候就像狼一样嚎叫)”可知，这些“复活”的冰原狼幼崽表现出了一些类似狼的行为。故选A。3．推理判断题。根据第五段中“Colossalisn’tjustrevivingthedirewolf.Theirlistincludesthewoollymammoth,dodoandTasmaniantiger.Theirmissiongoesbeyondde-extinction:theyalsousethesametechniquetopreventspeciesindangerfromdisappearing.Forexample,theybroughtbackfourredwolves,anendangeredspecies,inthesamewayofrestoringthedirewolf.(Colossal公司不仅仅是在复活冰原狼。它们的名单还包括猛犸象、渡渡鸟和塔斯马尼亚虎。它们的使命不仅仅是让灭绝的物种复活：它们还使用同样的技术来防止濒危物种消失。例如，他们用同样的方法带回了四种濒危物种红狼，就像恢复冰原狼一样)”可推知，作者提到红狼是为了展示Colossal公司在保护濒危物种方面的更广泛努力。故选D。4．推理判断题。根据第一段中“OnApril7,theUScompanyColossalBiosciencesannouncedrestoringthisspeciesviade-extinction—ahistoricfirst.(4月7日，美国ColossalBiosciences公司宣布通过“去灭绝”技术恢复这一物种，这是历史上的首次)”以及最后一段中“ColossalCEOBenLammarguesthatgeneticengineeringiscrucialtopreventthisloss.Yetsomewarntherecouldbeconsequences.Introducingnewspeciescancauseinvasivespecies,whilecloningoftenleadstohealthproblemsinanimalsandsurrogates.(Colossal公司首席执行官本•拉姆认为，基因工程对于防止这种损失至关重要。然而，也有人警告说可能会有后果。引入新物种可能会导致入侵物种，而克隆往往会导致动物和代孕者的健康问题)”可推知，作者在文章中既提到了Colossal公司的创新尝试，也提到了科学界的争议和潜在风险，因此作者对于去灭绝技术的态度是客观且谨慎的。故选B。【词汇积累】1.extinctadj.灭绝的；废除了的2.historicadj.历史（性）的；有历史记载的3.implantvt.移植；灌输；植入，插入vi.（受精卵）着床；被移植4.preservev.保持；保护；保险；腌制n.蜜饯；果酱；腌菜5.criticizev.批评，指责；评价，批判6.endangeredadj.（动物、鸟类等）濒危的，濒于灭绝的7.diversityn.多样性，多元性；差异，不同8.crucialadj.至关重要的，关键性的Passage2阅读理解Anambitiousplantogeneticallyengineeraversionofthewoollymammoth(长毛猛犸象),agiantthatdisappeared4,000yearsago,ismakingsomeprogress.Anewbiosciencesandgeneticscompany,Colossal,hasraised$15milliontocreateamammothhybridthatlooksexactlylikeitsextinctcounterpart.Thegoalisn’ttocloneamammoth,buttocreate,throughgeneticengineering,aliving,walkingelephant-mammothhybrid.ThescientistsrevealedtheyhadreprogrammedcellsfromanAsianelephant,thewoollymammoth’sclosestlivingrelative.Thesechangedcellscangrowintoanykindofelephantcell.Theresearchteamhasanalyzedmorethan50changestothegeneticcodeoftheAsianelephanttogiveitthecharacteristicsitneedstosurviveandthriveintheArctic.Thesecharacteristicsincludea10-centimeterlayerofinsulating(绝缘的)fat,fivedifferentkindsofhairincludingsomethatisuptoameterlong,andsmallerearsthatwillhelpthehybridtoleratethecold.ColossalbelievesthatbringingthewoollymammothbacktolifecouldpossiblyhelprestorethefragileArctictundra(冻原)ecosystem,whichisatriskastheworldwarms.Thecompanyhasclaimedthatmammoths,iftheyshouldreturntotheirnaturalhabitatintheArcticinsufficientnumbers,wouldhelpslowdownfrozensoilmelting.Somescientistsbelievethat,beforetheirextinction,animalssuchasmammothsandhorseskepttheearthfrozenunderneathbywalkingonthegrass,knockingdowntreesandpressingsnowtight.OnesmallstudyinSiberiapublishedin2021suggestedthatthepresenceoflargemammalssuchashorsesandreindeerresultedinlowersoiltemperaturesintheprotectedareawheretheywerekeptcomparedwithlandoutsidethatarea.ColossalalsoannouncedplanstobringsomeotheranimalsbacktolifesuchastheTasmaniantigerin2023andthedodoin2024,butitsworkonthemammothhasbeengoingonlongest.5．Whatdoestheunderlinedword“counterpart”inthefirstparagraphreferto?A．Endangeredanimal. B．Fellowspecies.C．Clonedelephant. D．Extractedcell.6．Whatcanwelearnaboutthehybrid?A．ItisvisuallysimilartotheAsianelephant.B．Itcangrowintoanytypesofelephantcell.C．Thickfatandsmallerearshelpitendurethesevereweather.D．Longhairlikeawoollycoatkeepsitfromthecoldandattacks.7．WhydoestheauthormentionthestudyinSiberiainParagraph3?A．Toillustratethepossibilityofreintroducingmammothstotheirnaturalhabitats.B．Tocomparedifferentkindsofnaturereserveswherelargemammalswerekept.C．Toindicatethelinkbetweentheextinctionoflargemammalsandclimatechange.D．ToshowthepotentialimpactofreturningmammothstotheArcticontheecosystem.8．Whatcanweinferfromthelastparagraph?A．Theprojectonbringingbackthemammothcoststhemost.B．TheTasmaniatigerandthedodoarealsolong-deadanimals.C．Colossalneedsincreasedinvestmenttoadvancetheprojects.D．Colossaliscompletelyconfidentinitstechnologyandscientists.【答案】5．B6．C7．D8．B【解析】本文是一篇说明文。文章主要讲述了一家生物科技公司成功创造了猛犸象近亲亚洲象的干细胞，为复活猛犸象迈出重要一步，引发环保和科学界的讨论。5．词句猜测题。根据第一段中“Anewbiosciencesandgeneticscompany,Colossal,hasraised$15milliontocreateamammothhybridthatlooksexactlylikeitsextinctcounterpart.Thegoalisn’ttocloneamammoth,buttocreate,throughgeneticengineering,aliving,walkingelephant-mammothhybrid.(一家名为Colossal的新型生物科学和遗传学公司已筹集到1500万美元，用于创造一种看起来与其灭绝的counterpart一模一样的猛犸象杂交品种。目标不是克隆猛犸象，而是通过基因工程创造一种活生生的、行走的大象-猛犸象杂交品种)”可知，此处指灭绝的猛犸象，counterpart意为“相对应的人或物”，所以此处指与现在的杂交品种相对应的物种，即“灭绝的猛犸象”，相当于“同类物种”。A.Endangeredanimal濒危动物；B.Fellowspecies同类生物；C.Clonedelephant克隆大象；DExtractedcell提取的细胞。故选B。6．细节理解题。根据第二段中“Thesechangedcellscangrowintoanykindofelephantcell.Theresearchteamhasanalyzedmorethan50changestothegeneticcodeoftheAsianelephanttogiveitthecharacteristicsitneedstosurviveandthriveintheArctic.Thesecharacteristicsincludea10-centimeterlayerofinsulating(绝缘的)fat,fivedifferentkindsofhairincludingsomethatisuptoameterlong,andsmallerearsthatwillhelpthehybridtoleratethecold.(这些改变的细胞可以生长成任何种类的大象细胞。研究小组分析了亚洲象基因组的50多处变化，使其具有在北极生存和繁衍所需的特征。这些特征包括一层10厘米厚的绝缘脂肪、五种不同的毛发(其中一些长达一米)以及较小的耳朵，这将帮助杂交品种抵御寒冷)”可知，杂交品种有10厘米厚的绝缘脂肪和较小的耳朵，这些可以帮助杂交品种忍受恶劣的天气。故选C。7．推理判断题。根据第三段中“OnesmallstudyinSiberiapublishedin2021suggestedthatthepresenceoflargemammalssuchashorsesandreindeerresultedinlowersoiltemperaturesintheprotectedareawheretheywerekeptcomparedwithlandoutsidethatarea.(2021年在西伯利亚进行的一项小型研究表明，在保护区内饲养的马和驯鹿等大型哺乳动物的存在，使得该区域的土壤温度比保护区外的土地更低)”可知，提到这项研究是为了说明猛犸象回归北极可能对生态系统产生的潜在影响，例如降低土壤温度、保护冻土层等。故选D。8．推理判断题。根据最后一段“ColossalalsoannouncedplanstobringsomeotheranimalsbacktolifesuchastheTasmaniantigerin2023andthedodoin2024,butitsworkonthemammothhasbeengoingonlongest.(Colossal公司还宣布计划于2023年复活塔斯马尼亚虎，于2024年复活渡渡鸟，不过其关于猛犸象的研究开展得最早)”可推知，塔斯马尼亚虎和渡渡鸟也是早已灭绝的动物。故选B。【长难句分析】【文章原句】ColossalbelievesthatbringingthewoollymammothbacktolifecouldpossiblyhelprestorethefragileArctictundra(冻原)ecosystem,whichisatriskastheworldwarms.【句式分析】这个句子是一个复合句。That后是宾语从句，whichisatriskastheworldwarms是宾语从句中的非限制性定语从句。【翻译】Colossal认为，让猛犸象复活可能有助于恢复脆弱的北极苔原生态系统，随着全球变暖，这个生态系统正面临风险。Passage3阅读七选五阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。FourRulesforSuccessfulPlantCloningPlantgrowershavetwochoiceswhenitcomestostartingnewplants:growingfromseed,orplantcloning.Andplantclonesofferadvantagesthatgrowingplantsfromseedcan’toffer.1,andaslongasyoudothecloningyourself,youknowwhothemotherplantisandhowyourcloneswillgrow,yield,andgetyouhigh.Butit’sanartandsciencetoplantcloning.Takeyourplantcuttingsfromahealthymotherplant.Plantcloninggivesyougeneticcopiesofyourmotherplant.2,yourclonesgetthebeststartpossibly.Avoidusingmotherplantsthataresick,orthatareplaguedwithpests.3.Mostplantclonesprefertemperaturesslightlyhigherthanyouridealgrowroomtemperature,andtheydon’tlikeadayandnightcyclewithatemperaturedropatnight.That’swhymostgrowersroottheircuttingsunderlightingthatstayson24hoursaday.Thelightingitselfcreatestemperaturestabilization.Temperaturesbetween74-77degreesFaretherangeyouwant.Cloneslikehighhumidity(湿度).Yourcuttingsneedahumidenvironmentinthe75-95%humidityrangeuntilthey’vecreatedrootsandareabletointakewaterthroughthem.That’swhymanyplantclonersusehumiditycovers.4,they’lldie.Usesterile(无菌的)equipmentandmaterials.Youalreadyfiguredoutthatyourscissors,knife,orothertoolsforcuttingcloneshastobeclean.Butyoualsowanttomakesureyoutrays,cloningcovers,androotzonemediaarecleanandsteriletoo.Don’treusecloningcubesorcloningpowdersandgels.5.Whenyoufollowtheseplantcloningtips,yourclonesuccessrateshouldbenearly100%.A．StartfresheverytimeB．UsekindLEDlightingC．GiveyourplantclonesconsistentclimateD．Growingfromclonesyou’resuretohaveallfemalesE．Ifyou’retaking20clonesandseeingonly10ofthemsurviveF．Untilyourcloneshavefunctioningroots,ifthey’reindryairG．Ifyourmotherplantsarestrong,healthy,andhavepotentgenetics【答案】1．D2．G3．C4．F5．A【解析】本文是一篇说明文，主要介绍了成功克隆植物的四个原则。1．承接句。根据后文中andaslongasyoudothecloningyourself,youknowwhothemotherplantisandhowyourcloneswillgrow,yield,andgetyouhigh可知，此处说明克隆植物的好处，得到的都是雌株。故选D。2．承接句。根据主题句中的关键词motherplant以及后一句yourclonesgetthebeststartpossibly.可知，本空说明要挑选强壮、健康，有强大的遗传力的母本植株。故选G。3．主题句。根据段中关键词temperatures可知，本段说明克隆植物所需的温度。故选C。4．总结句。选项中的dryair与主题句中的humidity相对应。故选F。5．总结句。本句与主题句和前文Don’treusecloningcubesorcloningpowdersandgels.相呼应，说明克隆植物时要用无菌的工具，最好是新的工具。故选A。Passage4完形填空Likeanythingbuiltbyevolution,thehumanbodyhasmanydownsides,teethwithoutexception.Adulthumansonlygetonesetofteeth,whichmustlastabout60years.However,a(n)1ofpoverty,sugar-richdietsandpoorhygienemeans2.5bnpeoplegloballysufferfromtoothdecay,inwhichacidproducedbymouth-livingbacteriaeatsawaythehardenamel(牙釉质)that2theoutsideofatooth,leadingtofurtherinfectionanddamage.Oncedecayhassetin,alladentistcandoistofillthegapwithartificialfilling.ButinapaperpublishedinCell,HanneleRuohola-Baker,astem-cellbiologistattheUniversityofWashington,andhercolleaguesofferapossible3.Stemcellshavethe4toturnthemselvesintoanyothertypeofcellinthebody.Itmaysoonbepossible,theresearchersclaim,tousethose5cellstoregrowatooth’senamelnaturally.Thefirststepwastoworkouthowenamelisproduced.Asenamel-makingcells,knownasameloblasts,disappearsoonafteraperson’sadultteethhavefinishedgrowing,theresearchers6samplesoftissuefromhumanfoetuses(胚胎),whichcontainplentyoffunctioningameloblasts.7,theycheckedtoseewhichgeneswereespeciallyactiveintheenamel-producingcells.Itturnedoutthatgenesdesignedtobindtocalciumwereparticularlybusy.8thatinformation,DrRuohola-Bakerandhercolleaguesnextcheckedtoseewhetherthestemcellscouldbepersuadedto9ameloblasts.Theteamdevisedvariousdrugsdesignedtoactivatethegenesexpressedinfunctioningameloblasts.Thatworked,withtheengineeredameloblastsproducingthesameproteinsasthenaturalsort.Fornow,theworkismoreconceptthanamedicaltreatment.Thenextstepistoboostenamelproductionfurther,withaviewto10beginningclinicaltrials.Thehopeisthat,oneday,medicalversionsoftheteam’sfindingscouldbeusedasbiologicalimplants,to11apatient’sdecayedteeth.Stem-cell-basedtherapiesarenottheonlyonesheadingtoclinicaltrials.Anothertreatment,knownasbiomimeticrepair,involvesrebuildingthetoothcrownusingsynthetic(人工合成的)proteins,whicharesimilar,butnotquite12,tohumanenamel.Theproteinscouldbeincludedintoothpasteandevencoughdrops.Butsyntheticformulationscanbeless13thanhumanenamel.Itwilltaketimeforeithertechnologytobecomereality.Onequestionishowdurabletheenamelmadebystem-cell-derivedameloblastsis.Anotherishowbesttodeliverthestemcellstoapatient’smouth.Butthesefindingsare14.Asanydentistwilltellyou,preventi