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下列为烟草花叶病毒具有的物质或结构是（ ）
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高三下学期生物《》真题及答案
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下列物质或结构中含胸腺嘧啶T的是
DNA聚合酶
烟草花叶病毒
ATP
线粒体
下列生物中不具有细胞结构的是
细菌
水螅
烟草花叶病毒
蚯蚓
下列生物中不具有细胞结构的是
变形虫
烟草花叶病毒
衣藻
酵母菌
烟草是我国重要的经济作物之一请分析回答以下问题1对进行分裂的烟草根尖细胞染色可以看到细胞内有一些能被
烟草花叶病毒噬菌体酵母菌蓝藻大肠杆菌体内都含有的物质或结构是
核酸
染色体
DNA
细胞结构
下列物质或结构中含胸腺嘧啶T.的是
蓝藻
烟草花叶病毒
ATP
DNA聚合酶
下列生物中不具有细胞结构的是
衣藻
烟草花叶病毒
草履虫
酵母菌
我们已经知道烟草花叶病毒是由RNA与蛋白质构成请设计一个简单实验证明烟草花叶病毒的遗传物质
科学家发现用烟草花叶病毒的RNA染烟草才能使烟草感染病毒而蛋白质不能．下列叙述错误的是
该实验能证明烟草花叶病毒的遗传物质是RNA
娴草花叶病毒与烟草细胞共有的核苜酸有4种
该实验与噬菌休侵染细菌实验的设计思路相同
烟草细胞为烟草花叶病毒增殖提供模板和原料
烟草花叶病毒是一种植物病毒其遗传物质是______
试述烟草花叶病毒的结构特点
简述烟草花叶病毒的构造
番茄花叶病毒的毒源有20多种最主要的是烟草花叶病毒和病 毒
黄瓜花叶病毒
芹菜花叶病毒
芜青花叶病毒
马铃薯 X 病毒
下列属于动物病毒的是
流行性感冒病毒、肝炎病毒
流行性感冒病毒、烟草花叶病毒
烟草花叶病毒、口蹄疫病毒
痢疾杆菌噬菌体、艾滋病病毒
下列物质或结构中含胸腺嘧啶T的是
蓝藻
烟草花叶病毒
ATP
DNA聚合酶
烟草花叶病毒只含有蛋白质和RNA从烟草花叶病毒中提取出来的蛋白质不能使烟草感染病毒但是从这些病毒中提
RNA是主要的遗传物质
RNA是烟草花叶病毒的遗传物质
烟草花叶病毒中蛋白质没有作用
有RNA的生物都是以RNA为遗传物质
TMVCMV和PVY分别代表烟草花叶病毒黄瓜花叶病毒马铃薯Y病毒
下列为乳酸杆菌和烟草花叶病毒均具有的物质或结构是
核糖核酸
磷脂
细胞质
核糖体
菠菜叶脉透明新叶变黄产生斑驳和向下卷曲这是菠菜感染引起的症状
黄瓜花叶病毒
芜菁花叶病毒
烟草花叶病毒
甜菜花叶病毒
下列属于动物病毒的一组是
流行性感冒病毒、肝炎病毒
流行性感冒病毒、烟草花叶病毒
烟草花叶病毒、口蹄疫病毒
痢疾杆菌噬菌体、艾滋病毒
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Tolearntothinkistolearntoquestion.Thosewhodon'tquestionnevertrulythinkforthemselves.Thesearesimplerolesthathavegovernedtheadvancementofscienceandhumanthoughtsincethebeginningoftime.Advancementsaremadewhenthinkersquestiontheoriesandintroducenewones.Unfortunatelyitisoftenthegreatandrespectedthinkerswhoendupslowingtheprogressofhumanthought.Aristotlewasabrilliantphilosopherwhosetheoriesexplainedmuchofthenaturalworldoftenincorrectly.Hewassoesteemedbythescientificcommunitythateven1200yearsafterhisdeathscientistswerestilltryingtobuilduponhismistakesratherthancorrectthem! Brilliantmindscanintimidateup﹣and﹣comingthinkerswhoarenotconfidentoftheirabilities.TheyoftenbelievetheyareinferiortothemindsofgiantssuchasAristotleleadingmanytoacceptcurrentparadigmsinsteadofquestioningthem. Ilikemanythinkersofthepastoncebelievedinmymentalinferiority.Iwascertainthatmyparentsmyteachers﹣adultsingeneral﹣werealwaysright.TheywerelikeatextbooktomeIdidn'tquestionwhatwaswrittenonthosepages.Irespectedthemandacceptedwhatevertheytoldme.Butthatattitudesoonchanged.Mymind'sindependencewasfirststimulatedintheclassroom. Astern65﹣year﹣oldelementary﹣schoolscienceteacheroncetoldmethatlightisatypeofwave.Iconfidentlywentthroughyearsofschoolbelievingthatlightisawave.OnedayhoweverIheardtheGermanexchangestudentmentionthatlightcouldbemadeupofparticles.AstheotherslaughedathisstatementIstartedtoquestionmybeliefs. Maybetheteachersandtextbookshadn'tgivenmethewholestory.Iwenttothelibrarydidsomeresearchandlearnedofthelight﹣as﹣a﹣waveversuslight﹣as﹣a﹣particledebate.IreadaboutEinstein'sdiscoveryofthedualnatureoflightandlearnedthefactsofaparadox悖论thatpuzzlestheworld'sgreatestthinkerstothisday.Lightbehavesasbothaparticleandawaveitisbothatonce.IrealizedIhadgonethroughlifeacceptingonlyhalfofthestoryasthewholetroth. EachnewyearbroughtmorenewfactsandIformulatedevenmorequestions.IfoundmyselfinthelibraryafterschooltryingtofindmyownanswerstogainamorecompleteunderstandingofwhatIthoughtIalreadyknew.Idiscoveredthatmyparentsandteachersareincredibletoolsinmyquestforknowledgebuttheyareneverthefinalword.Eventextbookscanbechallenged.IlearnedtoquestionmysourcesIlearnedtobeathinker.IoncebelievedthateverythingIlearnedathomeandatschoolwascertainbutIhavenowdiscoveredtore﹣examinewhennecessary. QuestionsaresaidtobethepathtoknowledgeandtrothandIplantocontinuequestioning.Howmanythingsdoweknowforsuretodaythatwewillquestioninthefuture?AtthismomentIknowthatoursunwillbumforanotherfivebillionyearsandIknownothingcanescapethegravityofablackhole.Thisknowledgehowevermaychangeinthenext20years﹣maybeeveninthenexttwo.Theonethingwecancontrolnowisouropennesstodiscovery.Questionsarethetoolsofopenmindsandopenmindsarethekeytointellectualadvancement. 1WhatdoestheexampleofAristotleinthefirstparagraphshow? A.Advancementsaremadewhenthinkersquestiontheories. B.Greatthinkersoftenmakemistakesandthencorrectthem. C.Heisthegreatestandrespectedphilosopherofalltime. D.Hugeinfluenceofgreatthinkersmayblockhumanthought. 2TheunderlinedwordintimidateinParagraph2means. A.encourage B.frighten C.strength D.persuade 3Whydidtheauthorbegantoquestionhispreviousbeliefs? A.Hewasinspiredbythedifferentideasfromanexchangestudent. B.Whathelearnedfromtextbooksbeforeturnedouttobewrong. C.Hewasnotsatisfiedwithhislifeanddesperatetoachievesuccess. D.Hewaslaughedatbyotherstudentsforhisunacceptablestatement. 4Accordingtothepassagetheauthor. A.determinestobeathinkerandquestioner B.alwaysthrowshimselfintothelaboratory C.neverdoubtswhathehaslearnedinthetextbook D.looksdownupongreatthinkersallthetime 5Whatcanweconcludefromthelastparagraph? A.Wehumanbeingsdon'tdaretopredictfuture. B.Theauthorisnotquitesureabouthisfuture. C.Thetheoryofblackholeswillchangeintwoyears. D.Questioningisnecessarytopromoteadvancement. 6Whatdoesthepassagemainlytalkabout? A.Followingroles. B.Questioninggiants. C.Challengingyourself. D.Predictingfuture.
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