2023届高三英语培优外刊阅读学案牛奶话题

高三英语培优外刊阅读班级：学号：姓名：外刊精选I人高马大的欧洲人：乳糖不耐也要喝牛奶上个月，新疆牛奶品牌麦趣尔产品抽检不合格，再次引发了关于如何选好牛奶的网络热议。实际上，很多中国人其实根本不适合喝牛奶，因为中国人乳糖不耐受的比例要远高于欧美人。而国外的一项新研究发现，原来我们印象中离不开牛奶的欧洲人，很多也是乳糖不耐受的体质。究竟为什么会有人乳糖不耐受？科学家还有哪些新发现？EarlyEuropeansCouldNotTolerateMilkbutDrankItAnyway,StudyFindsInmanyways,humansareweirdmammals.Andourrelationshipwithmilkisespeciallyweird.Ineverymammalianspecies,femalesproducemilktofeedtheiryoung.Thebabiesdigestthemilkwiththehelpofanenzymecalledlactase.Whentheyoungmammalsareweaned,theystopmakinglactase.Butitiscommonforourspeciestokeepconsumingmilkintoadulthood.What'smore,aboutone-thirdofpeoplecarrygeneticmutationsthatallowthemtoproducelactasethroughouttheirlives,makingiteasiertodigestmilk.Scientistshavelongsuspectedthatdairyconsumptionandthepersistenceoflactaserosetogetherinhumanhistory.Whenpeoplestartedherdingcattleandotherlivestocksome10,000yearsago,thetheorywent,thosewithamutationforlactasepersistencegainedanewsourceofcaloriesandprotein.Butanewstudysuggeststhatthetraditionalstorydoesnotholdup.ResearchershavefoundthatEuropeanswereconsumingmilkwithoutlactaseforthousandsofyears,despitethemiseryfromgasandcrampingitmighthavecaused.Overtheyears,scientistshavefoundmilkonthousandsofpotteryfragmentsacrossEuropeandneighboringregions.Forthenewstudy,thescientistsusedthisdatabasetocreateamapofmilkconsumptionoverthepast9,000years.【词汇过关】请写出下面文单词在文章中的中文意思。.tolerate['toIreit]v..weird[wiod]adj..consume[ksn'sju：m]v..cramp[kr<emp]v./n..fragment['frsegmsnt]n.【词块学习】请从文章中找到下面中文相对应的文词块。.借助于，利用.使做某事更容易.长期怀疑.理论是这样的.（这个故事没有）站得住脚拓展练习阅读理解Modemmedicine'sabilitytokeepusalivemakesittemptingtothinkhumanevolutionmayhavestopped.ButifwelookattherateofourDNA'sevolution,wecanseethathumanevolutionhasn'tstopped一itmayevenbehappeningfasterthanbefore.EvolutionisagradualchangetotheDNAofaspeciesovermanygenerations.Itcanoccurbynaturalselection,whencertaintraitscreatedbygeneticchangeshelpanorganismsurviveorreproduce.Suchgenesarethusmorelikelytobepassedontothenextgeneration,sotheyincreaseinfrequencyinapopulation.Gradually,thesechangesandtheirassociatedtraitsbecomemorecommonamongthewholegroup.BylookingatglobalstudiesofourDNA,wecanseeevidencethatnaturalselectionhasrecentlymadechangesandcontinuestodoso.Thoughmodernhealthcaredisruptsakeydrivingforceofevolutionbykeepingsomepeoplealivelonger,incountrieswithoutaccesstogoodhealthcare,populationsarecontinuingtoevolve.Survivorsofinfectiousdiseaseoutbreaksdrivenaturalselectionbygivingtheirgeneticresistancetooffspring.OurDNAshowsevidenceforrecentselectionforresistanceofkillerdiseaseslikeLassafeverandmalaria.Selectioninresponsetomalariaremainsinregionswherethediseaseremainscommon.Humansarealsoadaptingtotheirenvironment.GenechangeallowinghumanstoliveathighaltitudeshavebecomemorecommoninpopulationsinTibet,Ethiopia,andtheAndes.ThespreadofgeneticchangesinTibetispossiblythefastestevolutionarychangeinhumans,occurringoverthepast3,000years.Thisrapidincreaseinfrequencyofamutatedgenethatincreasesbloodoxygencontentgiveslocalsasurvivaladvantageinhigheraltitudes,resultinginmoresurvivingchildren.Dietisanothersourceforadaptations.Studiesshowthatnaturalselectionfavoringachangeallowingadultstoproducelactase-theenzyme(酶)thatbreaksdownmilksugars-iswhysomegroupsofpeoplecandigestmilk.Over80percentofnorthwestEuropeanscan,butinpartsofEastAsia,wheremilkismuchlesscommonlydrunk,aninabilitytodigestlactoseisthenorm.Likehighaltitudeadaptation,selectiontodigestmilkhasevolvedmorethanonceinhumansandmaybethestrongestkindofrecentselection.Yet,despitethesechanges,naturalselectiononlyaffectsabout8percentofourgenome.Butscientistscan'texplainwhysomegenesareevolvingmuchfasterthanothers.WemeasurethespeedofgeneevolutionbycomparinghumanDNAwiththatofotherspecies.Onefast-evolvinggeneishumanacceleratedregion1(HARI),whichisneededduringbraindevelopment.ArandomsectionofhumanDNAisonaveragemorethan98percentidenticaltothechimpcomparator,butHARIissofastevolvingthatit'sonlyaround85percentsimilar.Thoughscientistscanseethesechangesarehappening-andhowquickly-westilldon'tfullyunderstandwhyfastevolutionhappenstosomegenesbutnotothers..Whichofthefollowingstatementsmaytheauthoragreewith?A.Evolutionoccursamongseveralpeopleovernight.B.Genesmaychangeandsomearebeneficialtopeople'slives.C.Evolutionisdonewhenthewholepopulationpossessesacertaingene.D.Thechangedgenesleadingtohighersurvivalratesarechosendeliberately..Theunderlinedword“disrupts”.Theauthorillustrateshumans'ongoingevolutionwiththefollowingexamplesEXCEPTthat.A.somepeoplecanresistinfectiousdiseaseslikemalariaB.childreninTibettoleratelivingenvironmentswiththinairC.northwesternEuropeansdigestlactosebetterthanEastAsiansD.thehumangeneHARIresemblesthatofachimptoalesserextent.Whichofthefollowingmayserveasthetitle?A.WhatIsNaturalSelection?B.AreHumansStillEvolving?C.WhyWillCertainGenesEvolve?D.HowDoMutatedGenesFunction?外刊精选答案【词汇过关】请写出下面文单词在文章中的中文意思。.tolerate['tDIreit]v.容许,允许;忍受;容忍.weird[wlsd]adj.奇怪的;诡异的;怪诞的.consume[kon'sju：m]v.消费;吃;消耗，耗费4,cramp[kraemp]v./n.抽筋;痛性痉挛;（腹部）绞痛.fragment['frasgmont]n.碎片;片段【词块学习】请从文章中找到下面中文相对应的文词块。l