版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领
文档简介
雅思阅读模拟试题精选1.Washing,brushingandvarnishingfossils—allstandardconservationtreatmentsusedbymanyfossilhuntersandmuseumcuratorsalike—vastlyreducesthechancesofrecoveringancientDNA.2.Instead,excavatorsshouldbehandlingatleastsomeoftheirbountywithgloves,andfreezingsamplesastheyarefound,dirtandall,concludesapaperintheProceedingsoftheNationalAcademyofSciencestoday.3.AlthoughmanypalaeontologistsknowanecdotallythatthisisthebestwaytouptheoddsofextractinggoodDNA,Eva-MariaGeigloftheJacquesMonodInstituteinParis,France,andhercolleagueshavenowshownjusthowimportantconservationpracticescanbe.Thisinformation,theysay,needstobehammeredhomeamongthepeoplewhoareactuallyoutinthefielddiggingupbones.4.Geiglandhercolleagueslookedat3,200-year-oldfossilbonesbelongingtoasingleindividualofanextinctcattlespecies,calledanaurochs.ThefossilsweredugupatasiteinFranceattwodifferenttimes—eitherin1947,andstoredinamuseumcollection,orin,andconservedinsterileconditionsat-20oC.5.Theteam'sattemptstoextractDNAfromthe1947bonesallfailed.Thenewlyexcavatedfossils,however,allyieldedDNA.6.Becausetheboneshadbeenburiedforthesameamountoftime,andinthesameconditions,theconservationmethodhadtobetoblamesaysGeigl."AsmuchDNAwasdegradedinthese57yearsasinthe3,200yearsbefore,"shesays.Washin,washout7.Becausemanypalaeontologistsbasetheirworkontheshapeoffossilsalone,theirmethodsofconservationarenotdesignedtopreserveDNA,Geiglexplains.8.Thebiggestproblemishowtheyarecleaned.Fossilsareoftenwashedtogetheron-siteinalargebath,whichcanallowwater—andcontaminantsintheformofcontemporaryDNA—topermeateintotheporousbones."NotonlyistheauthenticDNAgettingwashedout,butcontaminationisgettingwashedin,"saysGeigl.9.MostancientDNAspecialistsknowthisalready,saysHendrikPoinar,anevolutionarygeneticistatMcMasterUniversityinOntario,Canada.Butthatdoesn'tmeanthatbestpracticehasbecomewidespreadamongthosewhoactuallyfindthefossils.10.GettingholdoffossilsthathavebeenpreservedwiththeirDNAinmindreliesoncloserelationshipsbetweenlab-basedgeneticistsandtheexcavators,sayspalaeogeneticistSvanteP??booftheMaxPlanckInstituteforEvolutionaryAnthropologyinLeipzig,Germany.Andthatonlyoccursinexceptionalcases,hesays.11.P??bo'steam,whichhasbeensequencingNeanderthalDNA,continuallyfacestheseproblems."WhenyouwanttostudyancienthumanandNeanderthalremains,there'sabigissueofcontaminationwithcontemporaryhumanDNA,"hesays.12.Thisdoesn'tmeanthatallmuseumspecimensarefatallyflawed,notesP??bo.TheNeanderthalfossilsthatwererecentlysequencedinhisownlab,forexample,hadbeenpartofamuseumcollectiontreatedinthetraditionalway.ButP??boiskeentoseesamplesoffossilsfromeverymajorfindpreservedinlinewithGeigl'srecommendations—justincase.Warmandwet14.Muchhumanculturaldevelopmenttookplaceintemperateregions.DNAdoesnotsurvivewellinwarmenvironmentsinthefirstplace,andcanvanishwhenfossilsarewashedandtreated.Forthisreason,Geiglsays,mostancientDNAstudieshavebeendoneonpermafrostsamples,suchasthewoollymammoth,oronremainsshelteredfromtheelementsincoldcaves—includingcavebearandNeanderthalfossils.15.Betterconservationmethods,andafocusonfreshfossils,couldboostDNAextractionfrommoredelicatespecimens,saysGeigl.Andthatcouldshedmorelightonthestoryofhumanevolution.(640wordsnature)
GlossaryPalaeontologists古生物学家Aurochs欧洲野牛Neanderthal(人类学)尼安德特人,旧石器时代旳古人类。Permafrost(地理)永冻层-Questions1-6AnswerthefollowingquestionsbyusingNOMORETHANTHREEWORDSforeachanswer.1.Howdidpeopletraditionallytreatfossils?2.WhatsuggestionsdoGeiglandhercolleaguesgiveonwhatshouldbedonewhenfossilsarefound?3.Whatproblemsmaybeposediffossilbonesarewashedon-site?NameONE.4.WhatcharacteristicdofossilboneshavetomakethemsusceptibletobecontaminatedwithcontemporaryDNAwhentheyarewashed?5.Whatcouldbebetterunderstoodwhenconservationtreatmentsareimproved?6.Thepassagementionedseveralanimalspeciesstudiedbyresearchers.Howmanyofthemarementioned?Questions7-11Dothefollowingstatementsagreewiththeinformationgiveninthepassage?PleasewriteTRUEifthestatementagreeswiththewriterFALSEifthestatementdoesnotagreewiththewriterNOTGIVENifthereisnoinformationaboutthisinthepassage7.IntheirpaperpublishedintheProceedingsoftheNationalAcademyofSciences,GeiglandhercolleagueshaveshownwhatconservationpracticesshouldbefollowedtopreserveancientDNA.8.ThefossilbonesthatGeiglandhercolleaguesstudiedareallfromthesameaurochs.9.Geneticistsdon‘thavetoworkonsite.10.OnlynewlyexcavatedfossilbonesusingnewconservationmethodssuggestedbyGeiglandhercolleaguescontainancientDNA.11.Paaboisstillworriedaboutthepotentialproblemscausedbytreatmentsoffossilsintraditionalway.Questions12-13CompletethefollowingthestatementsbychoosingletterA-Dforeachanswer.12.“Thisinformation”inparagraph3indicates:[A]ItiscriticaltofollowproperpracticesinpreservingancientDNA.[B]ThebestwayofgettinggoodDNAistohandlefossilswithgloves.[C]Fossilhuntersshouldwearhome-madehammerswhilediggingupbones.[D]Manypalaeontologistsknowhowoneshoulddointreatingfossils.13.ThestudyconductedbyGeiglandhercolleaguessuggests:[A]thefactthatancientDNAcannotberecoveredfromfossilbonesexcavatedinthepast.[B]thecorrelationbetweentheamountofburyingtimeandthatoftherecoveredDNA.[C]thepaceatwhichDNAdegrades.[D]thecorrelationbetweenconservationpracticesanddegradationofDNA.
1.washing,brushing,varnishing见第一段。2.handlingwithgloves/freezingsamples(anyoneofthetwo)见第二段。3.losingauthenticDNA/beingcontaminated/contamination(anyoneofthethree)见第八段“NotonlyistheauthenticDNAgettingwashedout,butcontaminationisgettingwashedin”(答beingcontaminated或contamination比较保险)4.theyareporousporous旳意思是多孔旳。见第八段“……whichcanallowwater—andcontaminantsintheformofcontemporaryDNA—topermeateintotheporousbones.”5.humanevolution见第十五段。其中“shedlightonsth”旳意思是使某事显得非常清晰,使人理解某事。6.4分别为第四段旳“anextinctcattlespecies,calle
温馨提示
- 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
- 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
- 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
- 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
- 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
- 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
- 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。
最新文档
- 2024年度待岗员工转岗安置服务协议书范本3篇
- 2024优蔬菜质量追溯体系建设项目合同3篇
- 2024年有限责任公司增资扩股、智慧城市建设项目合作及资源整合协议3篇
- 税务服装穿搭课程设计
- 2024年罗马柱安装项目标准协议书版B版
- 2024年精装大型公共场所装修协议书样本版B版
- 无球训练跑位课程设计
- 新部编人教版七年级下册语文《16 爱莲说 视频朗读》教学设计
- 电力电子课程设计邓
- 2024年原木家具定制加工合同范本3篇
- 炉渣炉灰采购合同模板
- 国家开放大学Python程序设计形考任务实验六-互联网评论数据分析及其展示综合案例
- GB/T 44899-2024商品条码散装和大宗商品编码与条码表示
- 施工企业五年规划
- 2024年保密知识测试试题附答案(综合卷)
- 高考英语一轮复习知识清单(全国版)专题06 语法填空倒装句100题(精练) 含答案及解析
- 侵入性器械(操作)相关感染防控制度的落实
- 江苏省南京市、盐城市2024届高三第一次模拟考试数学试题
- 北京东城北京二中2025届物理高一第一学期期末学业水平测试试题含解析
- 2024年度危废培训完整课件
- 英语漫谈今日中国学习通超星期末考试答案章节答案2024年
评论
0/150
提交评论