2016考研数学解析：概率论与数理统计主观题考点分析

一、选择题：1～8小题，每小题4分，共32分，下列每小题给出的四个选项中，只有一项符合题目要求的，请将所选项前的字母填在答题纸指定位置上.二、填空题：9~14小题，每小题4分，共24分，请将答案写在

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相关推荐：>>>2017年考研现场确认时间及地点汇总>>>全国各地2017年考研报考点汇总>>>2017年考研时间、研究生考试时间安排>>>2017年考研大纲下载及解析汇总>>>2017年全国硕士研究生招生简章专题新东方网校推荐：2017年考研政治、英语、数学课程！！点击进入免费试听>>Scientistshaveknownformorethantwodecadesthatcancerisadiseaseofthegenes.SomethingscramblestheDnainsideanucleus，andsuddenly，insteadofdividinginameasuredfashion，acellbeginstocopyitselffuriously.Unlikeanordinarycell，itneverstops.Butdescribingtheprocessisn'tthesameasfiguringitout.Cancercellsaresoradicallydifferentfromnormalonesthatit'salmostimpossibletountanglethesequenceofeventsthatmadethemthatway.Soforyearsresearchershavebeenattackingtheproblembytakingnormalcellsandtryingtodeterminewhatchangeswillturnthemcancerous——alwayswithoutsuccess.Untilnow.AccordingtoareportinthecurrentissueofNature，ateamofscientistsbasedatM.I.T.'sWhiteheadInstituteforBiomedicalResearchhasfinallymanagedtomakehumancellsmalignant——afeattheyaccomplishedwithtwodifferentcelltypesbyinsertingjustthreealteredgenesintotheirDNA.Whilethesemanipulationsweredoneonlyinlabdishesandwon'tleadtoanyimmediatetreatment，theyappeartobeacrucialstepinunderstandingthedisease.Thisisa“landmarkpaper，”wroteJonathanWeitzmanandMosheYanivofthePasteurInstituteinParis，inanaccompanyingcommentary.Thedramaticnewresulttracesbacktoabreakthroughin1983，whentheWhitehead'sRobertWeinbergandcolleaguesshowedthatmousecellswouldbecomecancerouswhenspikedwithtwoalteredgenes.Butwhentheytriedsuchalterationsonhumancells，theydidn'twork.Sincethen，scientistshavelearnedthatmousecellsdifferfromhumancellsinanimportantrespect：theyhavehigherlevelsofanenzymecalledtelomerase.Thatenzymekeepscaplikestructurescalledtelomeresontheendsofchromosomesfromgettingshorterwitheachroundofcelldivision.Suchshorteningispartofacell'sagingprocess，andsincecancercellskeepdividingforever，theWhiteheadgroupreasonedthatmakinghumancellsmoremouselikemightalsomakethemcancerous.Thestrategyworked.Thescientiststookconnective-tissueandkidneycellsandintrocedthreemutatedgenes——onethatmakescellsdividerapidly;anotherthatdisablestwosubstancesmeanttoreininexcessivedivision;andathirdthatpromotestheproctionoftelomerase，whichmadethecellsessentiallyimmortal.They'dcreatedatumorinatesttube.“Somepeoplebelievedthattelomerasewasn'tthatimportant，”saystheWhitehead'sWilliamHahn，thestudy'sleadauthor.“Thisallowsustosaywithsomecertaintythatitis.”Understandingcancercellsinthelabisn'tthesameasunderstandinghowitbehavesinalivingbody，ofcourse.Butbyteasingoutthekeydifferencesbetweennormalandmalignantcells，doctorsmaysomedaybeabletodesignteststopickupcancerinitsearlieststages.Thefindingcouldalsoleadtodrugstailoredtoattackspecifictypesofcancer，therebylesseningourdependenceontissue-destroyingchemotherapyandradiation.Beyondthat，theWhiteheadresearchsuggeststhatthisstubbornlycomplexdiseasemayhaveasimpleorigin，andtheidentificationofthatoriginmayturnouttobethemostimportantstepofall.注(1)：本文选自Time;08/09/99，p60，3/5p，2c注(2)：本文习题命题模仿对象2002年真题text41.Fromthefirstparagraph，welearnthat________________.[A]scientistshadunderstoodwhathappenedtonormalcellsthatmadethembehavestrangely[B]whenacellbeginstocopyitselfwithoutstopping，itbecomescancerous[C]normalcellsdonocopythemselves[D]theDNAinsideanucleusdividesregularly2.Whichofthefollowingstatementsistrueaccordingtothetext?[A]ThescientiststracedthesourceofcancersbyfiguringouttheirDNAorder.[B]Atreatmenttocancerswillbeavailablewithinayearortwo.[C]Thefindingpaveswayfortacklingcancer.[D]Thescientistssuccessfullyturnedcancerouscellsintohealthycells.3.Accordingtotheauthor，oneoftheproblemsinpreviouscancerresearchis________.[A]enzymekepttelomeresfromgettingshorter[B]scientistsdidn‘tknowthereexisteddifferentlevelsoftelomerasebetweenmousecellsandhumancells[C]scientistsfailedtounderstandtheconnectionbetweenacell‘sagingprocessandcelldivision.[D]humancellsaremouselike4.Whichofthefollowingbestdefinestheword“tailored”(Line4，Paragraph5)?[A]madespecifically[B]usedmainly[C]targeted[D]aimed5.TheWhiteheadresearchwillprobablyresultin___________.[A]athoroughunderstandingofthedisease[B]beatingoutcancers[C]solvingthecancermystery[D]drugsthatleavepatientslesspainful答案：BCBAD

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相关推荐：>>>2017年考研现场确认时间及地点汇总>>>全国各地2017年考研报考点汇总>>>2017年考研时间、研究生考试时间安排&g

相关推荐：>>>2017年考研现场确认时间及地点汇总>>>全国各地2017年考研报考点汇总>>>2017年考研时间、研究生考试时间安排&g

相关推荐：>>>2017年考研现场确认时间及地点汇总>>>全国各地2017年考研报考点汇总>>>2017年考研时间、研究生考试时间安排&g

【导语】当你真正想完成一件事时，根本不会在意别人是否看到。备考漫漫长路，无忧考网和你一起默默地走下去。以下是2020考研政治冲刺模拟题，一起来看看吧！一、选择题Ⅰ：下列每题给出的四个选项中，只有

相关推荐：>>>2017年考研现场确认时间及地点汇总>>>全国各地2017年考研报考点汇总>>>2017年考研时间、研究生考试时间安排&g