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? ?下面的短文后列出7个句子．请根据短文的内容对每个句子做出判断：如果泫句提供的是正确信息．请选择A；如果该句提供的是错误信息，请选择B：如果该句的信息文中没有提及．请选择C。 ...
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请根据以下资料说明使用5个规范句子描述全部所给信息内容要求1标题It’sharmfultoCivil
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下面的短文后列出了7个句子请根据短文的内容对每个句子做出判断如果该句提供的是正确信息请选择A如
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{{*HTML*}}??阅读下面的短文文章中有5处空白文章后面有6组文字请根据文章的内容选择 5组文字将其分别放回文章原有位置以恢复文章原貌 ?????????? ??{{B}}ANewMedicinetoTreatBothAIDSandHepatitisB{{/B}}? ?AmedicineapprovedlastmonthtotreatAIDS艾滋病alsoshowspromise againsthepatitisB乙型肝炎.??Thedrug3TCputsdownthe hepatitisBvirusinpeoplewithchronicinfectionsstoppingitsdamagetothe liverresearchersreported.??AboutonemillionAmericansare thoughttobeinfectedwithhepatitisBwhichcanleadtocirrhosis肝硬化 liverfailureandlivercancerinasmallproportionofvictimsifleft untreated.{{U}}?46?{{/U}}??It’sapreliminarystudy butthisispromising.Itlookslikeithasthepotentialtomakeasignificant impactonhepatitisBsaidDrJulesL.DienstagofMassachusettsGeneral Hospitalwhodirectedthestudy.??Currentlytheonlytreatment forhepatitisBisinterferon干扰素.Suchatreatmentcanpermanentlyeliminate thevirusinaboutone-thirdofpatients.{{U}}?47?{{/U}}? ?Inthelateststudydoctorsfoundthat3TCappearedtoknockoutthe viruspermanentlyinabout20%ofpatientswhengivenforthreemonths.{{U}} ?48?{{/U}}??Unlikeinterferon3TCisgiveninpill formandcarriesfewsideeffects.ThedrugwasapprovedbytheFoodandDrug AdministrationinNovemberforuseagainstAIDS.??Boththe hepatitisBvirusandtheAIDSvirusneedaproteintoreproduce.{{U}}?49 ?{{/U}}DoctorshavetestedsimilarAIDSdrugsagainsthepatitisB.Butall except3TChaveturnedouttobeineffectiveortootoxic有毒的.? ?DrJayHoofnagleoftheNationalInstitutesofHealthsaidanextstep willbetocombine3TCwithinterferontoseeifthetwodrugstogetherimprove thechanceofcuringhepatitisB.Itlooksextremelypromisinghesaidof 3TC.{{U}}?50?{{/U}}A．3TCisoneofagroupofdrugsthatblock productionofthisprotein.B．Interferonmustbeinjectedforfourtosix monthsandoftenhasunpleasantsideeffectsincludingflu-likesymptoms fatigueanddepression.C．Thehospitalisamongthebiggestonesin America.D．Dienstagsaidhehopesthatwithlongertreatmentthisresponse ratecanbedoubled.E．It’snottheanswerbutit’sastepintheright direction.F．Perhaps20%ofthesepatientshavelingering迁延性的infections thatwouldbenefitfromtreatment.{{*HTML*}}
TheCentralDogma ThoughitcomesasnosurprisethatthecompositionofDNAbetweendifferentorganismsisdifferentitisnotimmediatelyobviouswhythemusclecellsbloodcellsandbraincellsofanyoneparticularvertebrate脊椎动物aresodifferentintheirstructureandcompositionwhentheDNAofeveryoneoftheircellsisidentical.Thisisthekeytooneofthemostexcitingareasofmoderncellbiology.Indifferentcelltypesdifferentsetsofthetotalnumberofgenesgenome基因组areexpressed.InotherwordsdifferentregionsoftheDNAareactiveinthemusclecellsbloodcellsandbraincells. TounderstandhowthisdifferenceinDNAactivitycanleadtodifferencesincellstructureandcompositionitisnecessarytoconsiderwhatisoftenknownasthecentraldogma法则ofmolecularbiology:DNAmakesRNAmakeprotein.InmoleculartermsageneisthatportionofDNAthatencodesforasingleprotein.Thedictumonegenemakesoneproteinhasrequiredsomemodification改变withthediscoverythatsomeproteinsarecomposedofseveraldifferentpolypeptide多肽chainsbuttheonegenemakesonepolypeptideruledoeshold. DNAContainstheBlueprintforAllCellProteins. MessengerRNAisaprecisecopytranscriptofthecodedsequenceofnucleicacidbasesinDNAandthismessageistranslatedintoauniqueproteinmoleculeonspecialistorganellesribo-somespresentinthecytoplasm细胞质ofallcells.Proteins蛋白质whicharelargelymadeupofcarbonChydrogenHoxygenOandnitrogenNareconstructedfrom20differentcommonaminoacids.Theversatilityofproteinstheworkhorsemoleculesofthecellstemsfromtheimmensevarietyofmolecularshapesthatcanbecreatedbylinkingaminoacidstogetherindifferentsequences.Thesmallerproteinsconsistofonlyafewdozenaminoacidswhereasthelargeronesmaycontaininexcessof200aminoacidsalllinkedtogetherinalinear线状的chainbypeptidebonds. Astheproteinsarereleasedfromtheribosome核糖体theyfoldintouniqueshapesundertheinfluenceofchemicalforcesthatdependontheparticularsequenceofaminoacids.Sotheproteinprimarysequenceencodedinthegeneandfaithfullytranscribedandtranslatedintoanaminoacidchaindeterminesthethree-dimensionalstructureoftheemergingmolecule.Thehumanbodypossessessome30000differentkindsofproteinsandseveralmillioncopiesofmanyofthese.Eachplaysaspecificrole——forexamplehemoglobincarriesoxygeninthebloodactin肌动蛋白andmyosin肌球蛋白interacttogeneratemusclemovementandacetylcholine乙酸胆碱receptormoleculesmediatechemicaltransmissionbetweennerveandmusclecells. Enzymes—ProteinBiocatalysts Anessentialgroupofproteins—theenzymes酵素—actasbiologicalcatalysts催化剂andregulateallaspectsofcellmetabolism新陈代谢.Theyenablebreakdownofhigh-energyfoodmoleculescarbohydratestoprovideenergyforbiologicalreactionsandtheycontrolthesyntheticpathwaysthatresultinthegenerationoflipidse.g.fatscholesterol胆固醇andothervitalmembrane膜componentscarbohydrates碳水化合物sugarsstarch淀粉andcellulose纤维素thekeycomponentsofplantcellwallsandmanyvitalsmallbiomoleculesessentialforcellfunction. Stempara.3sent.3means______.
Dyslexia Asmanyas20%ofallchildrenintheUnitedStatessufferfromsomeformofthelearningdisorder2calleddyslexia. Expertsondyslexiasaythattheproblemisnotadisease.Theysaythatpersonswithdyslexiauseinformationinadifferentway.Oneoftheworldsgreatthinkersandscientists.AlbertEinsteinwasdyslexic.Einsteinsaidthatheneverthoughtinwordsthewaythatmostpeopledo.Hesaidthathethoughtinpicturesinstead. TheAmericaninventorThomasEdisonwasalsodyslexic.DyslexiafirstwasrecognizedinEuropeandtheUnitedStatesmorethan80yearsago.Manyyearspassedbeforedoctorsdiscoveredthatpersonswiththedisorderwerenotmentallyslowordisabled.Thedoctorsfoundthatthebrainsofpersonswithdyslexiaaredifferent. Inmostpeopletheleftsideofthebrain—thepartthatcontrolslanguageislargerthantherightside.Inpersonswithdyslexiatherightsideofthebrainisbigger.Doctorsarenotsurewhatcausesthisdifference.Howeverresearchhasshownthatdyslexiaismorecommoninmalesthaninfemalesanditisfoundmoreofteninpersonswhoarelefthanded4.Nooneknowsthecauseofdyslexiabutsomescientistsbelievethatitmayresultfromchemicalchangesinababy’’sbodylongbeforeitisborn.Theyaretryingtofindwaystoteachpersonswithdyslexia.Dyslexicpersonsthinkdifferentlyandneedspecialkindsofteachinghelp.Aftertheyhavesolvedtheirproblemswithlanguagetheyoftenshowthemselvestobeespeciallyintelligentorcreative. Manygreatthinkersandscientistsintheworldaredyslexic.
Itwasveryhardtograspwhatheactuallymeant.
{{*HTML*}}??阅读下面的短文文章中有5处空白文章后面有6组文字请根据文章的内容选择 5组文字将其分别放回文章原有位置以恢复文章原貌 ?????????? ??{{B}}ANewMedicinetoTreatBothAIDSandHepatitisB{{/B}}? ?AmedicineapprovedlastmonthtotreatAIDS艾滋病alsoshowspromise againsthepatitisB乙型肝炎.??Thedrug3TCputsdownthe hepatitisBvirusinpeoplewithchronicinfectionsstoppingitsdamagetothe liverresearchersreported.??AboutonemillionAmericansare thoughttobeinfectedwithhepatitisBwhichcanleadtocirrhosis肝硬化 liverfailureandlivercancerinasmallproportionofvictimsifleft untreated.{{U}}?46?{{/U}}??It’sapreliminarystudy butthisispromising.Itlookslikeithasthepotentialtomakeasignificant impactonhepatitisBsaidDrJulesL.DienstagofMassachusettsGeneral Hospitalwhodirectedthestudy.??Currentlytheonlytreatment forhepatitisBisinterferon干扰素.Suchatreatmentcanpermanentlyeliminate thevirusinaboutone-thirdofpatients.{{U}}?47?{{/U}}? ?Inthelateststudydoctorsfoundthat3TCappearedtoknockoutthe viruspermanentlyinabout20%ofpatientswhengivenforthreemonths.{{U}} ?48?{{/U}}??Unlikeinterferon3TCisgiveninpill formandcarriesfewsideeffects.ThedrugwasapprovedbytheFoodandDrug AdministrationinNovemberforuseagainstAIDS.??Boththe hepatitisBvirusandtheAIDSvirusneedaproteintoreproduce.{{U}}?49 ?{{/U}}DoctorshavetestedsimilarAIDSdrugsagainsthepatitisB.Butall except3TChaveturnedouttobeineffectiveortootoxic有毒的.? ?DrJayHoofnagleoftheNationalInstitutesofHealthsaidanextstep willbetocombine3TCwithinterferontoseeifthetwodrugstogetherimprove thechanceofcuringhepatitisB.Itlooksextremelypromisinghesaidof 3TC.{{U}}?50?{{/U}}A．3TCisoneofagroupofdrugsthatblock productionofthisprotein.B．Interferonmustbeinjectedforfourtosix monthsandoftenhasunpleasantsideeffectsincludingflu-likesymptoms fatigueanddepression.C．Thehospitalisamongthebiggestonesin America.D．Dienstagsaidhehopesthatwithlongertreatmentthisresponse ratecanbedoubled.E．It’snottheanswerbutit’sastepintheright direction.F．Perhaps20%ofthesepatientshavelingering迁延性的infections thatwouldbenefitfromtreatment.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
Dyslexia Asmanyas20%ofallchildrenintheUnitedStatessufferfromsomeformofthelearningdisorder2calleddyslexia. Expertsondyslexiasaythattheproblemisnotadisease.Theysaythatpersonswithdyslexiauseinformationinadifferentway.Oneoftheworldsgreatthinkersandscientists.AlbertEinsteinwasdyslexic.Einsteinsaidthatheneverthoughtinwordsthewaythatmostpeopledo.Hesaidthathethoughtinpicturesinstead. TheAmericaninventorThomasEdisonwasalsodyslexic.DyslexiafirstwasrecognizedinEuropeandtheUnitedStatesmorethan80yearsago.Manyyearspassedbeforedoctorsdiscoveredthatpersonswiththedisorderwerenotmentallyslowordisabled.Thedoctorsfoundthatthebrainsofpersonswithdyslexiaaredifferent. Inmostpeopletheleftsideofthebrain—thepartthatcontrolslanguageislargerthantherightside.Inpersonswithdyslexiatherightsideofthebrainisbigger.Doctorsarenotsurewhatcausesthisdifference.Howeverresearchhasshownthatdyslexiaismorecommoninmalesthaninfemalesanditisfoundmoreofteninpersonswhoarelefthanded4.Nooneknowsthecauseofdyslexiabutsomescientistsbelievethatitmayresultfromchemicalchangesinababy’’sbodylongbeforeitisborn.Theyaretryingtofindwaystoteachpersonswithdyslexia.Dyslexicpersonsthinkdifferentlyandneedspecialkindsofteachinghelp.Aftertheyhavesolvedtheirproblemswithlanguagetheyoftenshowthemselvestobeespeciallyintelligentorcreative. Theleftsideofthebraininadyslexicpersonisbiggerthantherightside.
Johnhasalwaysremainedloyaltohisfamilyandfriends.
Theworkersfinallycalledoffthestrike.
TheAsianFluVirus In1957adoctorinSingaporenoticedthathospitalsweretreatinganunusualnumberofinfluenza-likecases.Influenzaissometimescalledfluorasbadcold.Hetookspecimensfromthethroatsofpatientsinhishospitalandwasabletofindthevirusofthisinfluenza. Therearethreemaintypesoftheinfluenzavirus.ThemostimportantofthesearetypesAandBeachofthemhavingseveralsub-groups.WiththeinstrumentsatthehospitalthedoctorrecognizedthattheoutbreakwasduetoavirusgroupAbuthedidnotknowthesub-group.HereportedtheoutbreaktotheWorldHealthOrganizationinGeneva.W.H.0.publishedtheimportantnewsalongsidereportsofasimilaroutbreakinHongKongwhereabout15%-20%ofthepopulationhadbecomeill. AssoonastheLondondoctorsreceivedthepackageofthroatsamplestheybeganthestandardtests.Theyfoundthatbyreproducingitselfataveryhighspeedthevirushadmultipliedmorethanamilliontimeswithintwodays.Continuingtheircarefulteststhedoctorscheckedtheeffectofdrugsusedagainstalltheknownsub-groupsoftypeAvirusonthisvirus.Noneofthemgaveanyprotection.Thisthenwassomethingnew:anewinfluenzavirusagainstwhichthepeopleoftheworldhadnoreadyhelpwhatsoever. Havingisolatedthevirustheywereworkingwiththetwodoctorsnowconductedtestsonsomespeciallyselectedanimalswhichcontractinfluenzainthesamewayashumanbeingsdo.Inashorttimetheusualsignsofthediseaseappeared.Theseexperimentsrevealedthatthenewvirusspreadeasilybutthatitwasnotakiller.ScientistslikegeneralpubliccalleditsimplyAsianflu. ItcanbeinferredfromthispassagethattheAsianflu______.
Astudentstickingcloselytothedisciplinesoftheschoolisoftenpraisedbythemasterandteachers.
OntheTrain ThenighttrainfromGlasgowwassocrowdedthatDonaldwhowasonhiswaytoLondontofindatemporaryjobfortheuniversityvacationwishedthathehaddecidedtotravelbyday.Hehadneverbeensohardup. Hegotonthetrainandwalkedalongthecorridorofthesecond-classcompartments.Hecouldn’’tfindaseatanywhere.Hecouldnotaffordtotravelfirstclassandhedidnotwanttostandinthecorridor.Neitherdidhewanttositonhissuitcase.Hewassotiredthathedecidedtositdowninafirstclasscompartmentatleastforawhile.Hesoonfoundonewithasingleoccupant乘客agentlemanreadingdocumentsfromabriefcase.Withtheself-assuranceofafirstclasstravelerheopenedthedoorandwentin.Nosoonerhadhesatdownthantheticketinspectorarrived.Whatbadluck!Nowhewouldhavetopaytheexcess额外的fare.Asheturnedouthispockettofindenoughmoneyhesawthegentlemanwaswatchinghimwithamusement.Itwashumiliating令人感到羞辱的.Howeverhewassotiredthathesoonfellasleep. Presentlyhearinganoisehehalfopenedhiseyes.Notonlydidhenoticethathistravelingcompanionhadgonebuthealsosawthatarough-lookingmanwassearchingthroughthebusinessman’’sbriefcase.Donaldgrabbedthebriefcaseandwrenched猛夺itfreekickingattheman’’sleg.Themanfled. ThenthebusinessmanreturnedandfoundDonaldholdingthebriefcaseandpeeringinsideit.Donaldrealizedthathewasinquiteanawkwardsituationbutthemanwassmiling.Norwasthistheonlysurprisingthing.NotonlywasthegentlemanwhointroducedhimselfasMr.SmithsmilingbuthethankedDonaldwarmly.OnhiswaybacktothecompartmentMr.Smithhadseenthemanleavinginagreathurry.HehadsoquicklyassessedthesituationthatheknewDonaldwasinnocent. OnlyafteralongchatinwhichDonaldwasaskedmanyquestionsabouthimselfdidDonalddiscoverthatMr.SmithwasinfactmanagingdirectorofalargefactoryinLondon.DonaldhadneverimaginedthatthisstrangeincidentwouldhelphimtofindajobbutjustastheywereleavingthetrainMr.SmithofferedhimthepostoftemporaryNightSecurityOfficerforhisfactory. ThetrainDonaldtookwas______.
TheAsianFluVirus In1957adoctorinSingaporenoticedthathospitalsweretreatinganunusualnumberofinfluenza-likecases.Influenzaissometimescalledfluorasbadcold.Hetookspecimensfromthethroatsofpatientsinhishospitalandwasabletofindthevirusofthisinfluenza. Therearethreemaintypesoftheinfluenzavirus.ThemostimportantofthesearetypesAandBeachofthemhavingseveralsub-groups.WiththeinstrumentsatthehospitalthedoctorrecognizedthattheoutbreakwasduetoavirusgroupAbuthedidnotknowthesub-group.HereportedtheoutbreaktotheWorldHealthOrganizationinGeneva.W.H.0.publishedtheimportantnewsalongsidereportsofasimilaroutbreakinHongKongwhereabout15%-20%ofthepopulationhadbecomeill. AssoonastheLondondoctorsreceivedthepackageofthroatsamplestheybeganthestandardtests.Theyfoundthatbyreproducingitselfataveryhighspeedthevirushadmultipliedmorethanamilliontimeswithintwodays.Continuingtheircarefulteststhedoctorscheckedtheeffectofdrugsusedagainstalltheknownsub-groupsoftypeAvirusonthisvirus.Noneofthemgaveanyprotection.Thisthenwassomethingnew:anewinfluenzavirusagainstwhichthepeopleoftheworldhadnoreadyhelpwhatsoever. Havingisolatedthevirustheywereworkingwiththetwodoctorsnowconductedtestsonsomespeciallyselectedanimalswhichcontractinfluenzainthesamewayashumanbeingsdo.Inashorttimetheusualsignsofthediseaseappeared.Theseexperimentsrevealedthatthenewvirusspreadeasilybutthatitwasnotakiller.ScientistslikegeneralpubliccalleditsimplyAsianflu. Theoutbreakwasduetoavirusinpara.2meansthatitwas______byavirus.
Itshardtoalteroneshabits.
OntheTrain ThenighttrainfromGlasgowwassocrowdedthatDonaldwhowasonhiswaytoLondontofindatemporaryjobfortheuniversityvacationwishedthathehaddecidedtotravelbyday.Hehadneverbeensohardup. Hegotonthetrainandwalkedalongthecorridorofthesecond-classcompartments.Hecouldn’’tfindaseatanywhere.Hecouldnotaffordtotravelfirstclassandhedidnotwanttostandinthecorridor.Neitherdidhewanttositonhissuitcase.Hewassotiredthathedecidedtositdowninafirstclasscompartmentatleastforawhile.Hesoonfoundonewithasingleoccupant乘客agentlemanreadingdocumentsfromabriefcase.Withtheself-assuranceofafirstclasstravelerheopenedthedoorandwentin.Nosoonerhadhesatdownthantheticketinspectorarrived.Whatbadluck!Nowhewouldhavetopaytheexcess额外的fare.Asheturnedouthispockettofindenoughmoneyhesawthegentlemanwaswatchinghimwithamusement.Itwashumiliating令人感到羞辱的.Howeverhewassotiredthathesoonfellasleep. Presentlyhearinganoisehehalfopenedhiseyes.Notonlydidhenoticethathistravelingcompanionhadgonebuthealsosawthatarough-lookingmanwassearchingthroughthebusinessman’’sbriefcase.Donaldgrabbedthebriefcaseandwrenched猛夺itfreekickingattheman’’sleg.Themanfled. ThenthebusinessmanreturnedandfoundDonaldholdingthebriefcaseandpeeringinsideit.Donaldrealizedthathewasinquiteanawkwardsituationbutthemanwassmiling.Norwasthistheonlysurprisingthing.NotonlywasthegentlemanwhointroducedhimselfasMr.SmithsmilingbuthethankedDonaldwarmly.OnhiswaybacktothecompartmentMr.Smithhadseenthemanleavinginagreathurry.HehadsoquicklyassessedthesituationthatheknewDonaldwasinnocent. OnlyafteralongchatinwhichDonaldwasaskedmanyquestionsabouthimselfdidDonalddiscoverthatMr.SmithwasinfactmanagingdirectorofalargefactoryinLondon.DonaldhadneverimaginedthatthisstrangeincidentwouldhelphimtofindajobbutjustastheywereleavingthetrainMr.SmithofferedhimthepostoftemporaryNightSecurityOfficerforhisfactory. Mr.SmithrealizedthatDonaldwasinnocent______.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
Allforeigntroopsmustwithdrawfromthecountry.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
TheCentralDogma ThoughitcomesasnosurprisethatthecompositionofDNAbetweendifferentorganismsisdifferentitisnotimmediatelyobviouswhythemusclecellsbloodcellsandbraincellsofanyoneparticularvertebrate脊椎动物aresodifferentintheirstructureandcompositionwhentheDNAofeveryoneoftheircellsisidentical.Thisisthekeytooneofthemostexcitingareasofmoderncellbiology.Indifferentcelltypesdifferentsetsofthetotalnumberofgenesgenome基因组areexpressed.InotherwordsdifferentregionsoftheDNAareactiveinthemusclecellsbloodcellsandbraincells. TounderstandhowthisdifferenceinDNAactivitycanleadtodifferencesincellstructureandcompositionitisnecessarytoconsiderwhatisoftenknownasthecentraldogma法则ofmolecularbiology:DNAmakesRNAmakeprotein.InmoleculartermsageneisthatportionofDNAthatencodesforasingleprotein.Thedictumonegenemakesoneproteinhasrequiredsomemodification改变withthediscoverythatsomeproteinsarecomposedofseveraldifferentpolypeptide多肽chainsbuttheonegenemakesonepolypeptideruledoeshold. DNAContainstheBlueprintforAllCellProteins. MessengerRNAisaprecisecopytranscriptofthecodedsequenceofnucleicacidbasesinDNAandthismessageistranslatedintoauniqueproteinmoleculeonspecialistorganellesribo-somespresentinthecytoplasm细胞质ofallcells.Proteins蛋白质whicharelargelymadeupofcarbonChydrogenHoxygenOandnitrogenNareconstructedfrom20differentcommonaminoacids.Theversatilityofproteinstheworkhorsemoleculesofthecellstemsfromtheimmensevarietyofmolecularshapesthatcanbecreatedbylinkingaminoacidstogetherindifferentsequences.Thesmallerproteinsconsistofonlyafewdozenaminoacidswhereasthelargeronesmaycontaininexcessof200aminoacidsalllinkedtogetherinalinear线状的chainbypeptidebonds. Astheproteinsarereleasedfromtheribosome核糖体theyfoldintouniqueshapesundertheinfluenceofchemicalforcesthatdependontheparticularsequenceofaminoacids.Sotheproteinprimarysequenceencodedinthegeneandfaithfullytranscribedandtranslatedintoanaminoacidchaindeterminesthethree-dimensionalstructureoftheemergingmolecule.Thehumanbodypossessessome30000differentkindsofproteinsandseveralmillioncopiesofmanyofthese.Eachplaysaspecificrole——forexamplehemoglobincarriesoxygeninthebloodactin肌动蛋白andmyosin肌球蛋白interacttogeneratemusclemovementandacetylcholine乙酸胆碱receptormoleculesmediatechemicaltransmissionbetweennerveandmusclecells. Enzymes—ProteinBiocatalysts Anessentialgroupofproteins—theenzymes酵素—actasbiologicalcatalysts催化剂andregulateallaspectsofcellmetabolism新陈代谢.Theyenablebreakdownofhigh-energyfoodmoleculescarbohydratestoprovideenergyforbiologicalreactionsandtheycontrolthesyntheticpathwaysthatresultinthegenerationoflipidse.g.fatscholesterol胆固醇andothervitalmembrane膜componentscarbohydrates碳水化合物sugarsstarch淀粉andcellulose纤维素thekeycomponentsofplantcellwallsandmanyvitalsmallbiomoleculesessentialforcellfunction. Thebesttitleofthispassageis______.
{{*HTML*}}??阅读下面的短文文章中有5处空白文章后面有6组文字请根据文章的内容选择 5组文字将其分别放回文章原有位置以恢复文章原貌 ?????????? ??{{B}}ANewMedicinetoTreatBothAIDSandHepatitisB{{/B}}? ?AmedicineapprovedlastmonthtotreatAIDS艾滋病alsoshowspromise againsthepatitisB乙型肝炎.??Thedrug3TCputsdownthe hepatitisBvirusinpeoplewithchronicinfectionsstoppingitsdamagetothe liverresearchersreported.??AboutonemillionAmericansare thoughttobeinfectedwithhepatitisBwhichcanleadtocirrhosis肝硬化 liverfailureandlivercancerinasmallproportionofvictimsifleft untreated.{{U}}?46?{{/U}}??It’sapreliminarystudy butthisispromising.Itlookslikeithasthepotentialtomakeasignificant impactonhepatitisBsaidDrJulesL.DienstagofMassachusettsGeneral Hospitalwhodirectedthestudy.??Currentlytheonlytreatment forhepatitisBisinterferon干扰素.Suchatreatmentcanpermanentlyeliminate thevirusinaboutone-thirdofpatients.{{U}}?47?{{/U}}? ?Inthelateststudydoctorsfoundthat3TCappearedtoknockoutthe viruspermanentlyinabout20%ofpatientswhengivenforthreemonths.{{U}} ?48?{{/U}}??Unlikeinterferon3TCisgiveninpill formandcarriesfewsideeffects.ThedrugwasapprovedbytheFoodandDrug AdministrationinNovemberforuseagainstAIDS.??Boththe hepatitisBvirusandtheAIDSvirusneedaproteintoreproduce.{{U}}?49 ?{{/U}}DoctorshavetestedsimilarAIDSdrugsagainsthepatitisB.Butall except3TChaveturnedouttobeineffectiveortootoxic有毒的.? ?DrJayHoofnagleoftheNationalInstitutesofHealthsaidanextstep willbetocombine3TCwithinterferontoseeifthetwodrugstogetherimprove thechanceofcuringhepatitisB.Itlooksextremelypromisinghesaidof 3TC.{{U}}?50?{{/U}}A．3TCisoneofagroupofdrugsthatblock productionofthisprotein.B．Interferonmustbeinjectedforfourtosix monthsandoftenhasunpleasantsideeffectsincludingflu-likesymptoms fatigueanddepression.C．Thehospitalisamongthebiggestonesin America.D．Dienstagsaidhehopesthatwithlongertreatmentthisresponse ratecanbedoubled.E．It’snottheanswerbutit’sastepintheright direction.F．Perhaps20%ofthesepatientshavelingering迁延性的infections thatwouldbenefitfromtreatment.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
Throughaprocedureknownastime-sharingonelargecomputercanbeemployedsimultaneouslybylotsofsmallusers.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
Thetrainstoppedabruptlymakinguswonderwherewewere.
Dyslexia Asmanyas20%ofallchildrenintheUnitedStatessufferfromsomeformofthelearningdisorder2calleddyslexia. Expertsondyslexiasaythattheproblemisnotadisease.Theysaythatpersonswithdyslexiauseinformationinadifferentway.Oneoftheworldsgreatthinkersandscientists.AlbertEinsteinwasdyslexic.Einsteinsaidthatheneverthoughtinwordsthewaythatmostpeopledo.Hesaidthathethoughtinpicturesinstead. TheAmericaninventorThomasEdisonwasalsodyslexic.DyslexiafirstwasrecognizedinEuropeandtheUnitedStatesmorethan80yearsago.Manyyearspassedbeforedoctorsdiscoveredthatpersonswiththedisorderwerenotmentallyslowordisabled.Thedoctorsfoundthatthebrainsofpersonswithdyslexiaaredifferent. Inmostpeopletheleftsideofthebrain—thepartthatcontrolslanguageislargerthantherightside.Inpersonswithdyslexiatherightsideofthebrainisbigger.Doctorsarenotsurewhatcausesthisdifference.Howeverresearchhasshownthatdyslexiaismorecommoninmalesthaninfemalesanditisfoundmoreofteninpersonswhoarelefthanded4.Nooneknowsthecauseofdyslexiabutsomescientistsbelievethatitmayresultfromchemicalchangesinababy’’sbodylongbeforeitisborn.Theyaretryingtofindwaystoteachpersonswithdyslexia.Dyslexicpersonsthinkdifferentlyandneedspecialkindsofteachinghelp.Aftertheyhavesolvedtheirproblemswithlanguagetheyoftenshowthemselvestobeespeciallyintelligentorcreative. Itisbelievedthatdyslexiaisrelatedtothebadhabitsofababy’smother.
OntheTrain ThenighttrainfromGlasgowwassocrowdedthatDonaldwhowasonhiswaytoLondontofindatemporaryjobfortheuniversityvacationwishedthathehaddecidedtotravelbyday.Hehadneverbeensohardup. Hegotonthetrainandwalkedalongthecorridorofthesecond-classcompartments.Hecouldn’’tfindaseatanywhere.Hecouldnotaffordtotravelfirstclassandhedidnotwanttostandinthecorridor.Neitherdidhewanttositonhissuitcase.Hewassotiredthathedecidedtositdowninafirstclasscompartmentatleastforawhile.Hesoonfoundonewithasingleoccupant乘客agentlemanreadingdocumentsfromabriefcase.Withtheself-assuranceofafirstclasstravelerheopenedthedoorandwentin.Nosoonerhadhesatdownthantheticketinspectorarrived.Whatbadluck!Nowhewouldhavetopaytheexcess额外的fare.Asheturnedouthispockettofindenoughmoneyhesawthegentlemanwaswatchinghimwithamusement.Itwashumiliating令人感到羞辱的.Howeverhewassotiredthathesoonfellasleep. Presentlyhearinganoisehehalfopenedhiseyes.Notonlydidhenoticethathistravelingcompanionhadgonebuthealsosawthatarough-lookingmanwassearchingthroughthebusinessman’’sbriefcase.Donaldgrabbedthebriefcaseandwrenched猛夺itfreekickingattheman’’sleg.Themanfled. ThenthebusinessmanreturnedandfoundDonaldholdingthebriefcaseandpeeringinsideit.Donaldrealizedthathewasinquiteanawkwardsituationbutthemanwassmiling.Norwasthistheonlysurprisingthing.NotonlywasthegentlemanwhointroducedhimselfasMr.SmithsmilingbuthethankedDonaldwarmly.OnhiswaybacktothecompartmentMr.Smithhadseenthemanleavinginagreathurry.HehadsoquicklyassessedthesituationthatheknewDonaldwasinnocent. OnlyafteralongchatinwhichDonaldwasaskedmanyquestionsabouthimselfdidDonalddiscoverthatMr.SmithwasinfactmanagingdirectorofalargefactoryinLondon.DonaldhadneverimaginedthatthisstrangeincidentwouldhelphimtofindajobbutjustastheywereleavingthetrainMr.SmithofferedhimthepostoftemporaryNightSecurityOfficerforhisfactory. Accordingtoparagraphs1and2whichofthefollowingstatementsaboutDonaldisNOTtrue?
{{*HTML*}}??阅读下面的短文文中有15处空白每处空白给出了4个选项请根据短文的内容从4个选项中选择1个最佳答案 ??????? ??????????? ?{{B}}ASpecialClock{{/B}}??Everylivingthinghaswhat scientistscallabiologicalclockthatcontrolsbehavior.Thebiologicai clock______51plantswhentoformflowersandwhentheflowersshouldopen.It tellsinsectswhento______52theprotectivecocoon防护卵袋andflyawayand ittellsanimalsandhumanbeingswhentoeatsleepandwake.? ?Eventsoutsidetheplantandanimal______53theactionsofsome biologicalclocks.Scientistsrecentlyfoundforexamplethatatinyanimal changesthecolorofitsfurbecauseofthe______54ofhoursofdaylight.In theshort______55ofwinteritsfurbecomeswhite.Thefurbecomesgraybrown in______56inthelongerhoursofdaylightinsummer.??Inner signalscontrolother______57clocks.Germanscientistsfoundthatsomekind ofinternalclockseems’toorderbirdstobegintheirlongmigration______58 twiceeachyear.Birds______59fromflyingbecomerestlesswhenitistimefor thetrip______60theybecomecalmagainwhenthetimeoftheflighthas ended.??Scientistssaytheyarebeginningtolearn which______61ofthebraincontainbiologicalclocks.AnAmericanresearcher MartinMoorheadsaidasmallgroupofcellsnearthefrontofthe brain______62tocontrolthetimingofsomeofouractions.These______63 tellapersonwhentowakewhento______64andwhentoseekfood.Scientists saythereprobablyareotherbiologicalclockCellsthat______65otherbody activities.
{{*HTML*}}{{B}}第三篇{{/B}} ??????? ???{{B}}IstheNewsBelievable?{{/B}}??Unlessyou havegonethroughtheexperienceyourselforwatchedalovedone’sstruggle youreallyhavenoideajusthowdesperatecancercanmakeyou.Youprayyou rageyoubargainwithGodbutmostofallyouclutchatanyhopenomatter howremoteofasecondchanceatlife.??Forafewexciteddays lastweekhoweveritseemedasifthewholeworldwasacancerpatientand thatallhumankindhadbeengrantedareprieve痛苦减轻.Triggeredbyafront-page medicalnewsstoryintheusuallyreservedNewYorkTimesallanybodywas talkingabout—ontheradioontelevisionontheInternetinphonecallsto friendsandrelatives—wasthereportthatacombinationoftwonewdrugs couldastheTimesputitcurecancerintwoyears.??Ina matterofhourspatientshadjammedtheirdoctors’phonelinesbeggingfora chancetotestthemiraclecancercure.Cancerscientistsracedtothephonesto makesureeveryoneknewabouttheirresearchtoogeneratinganewroundof headlines.??Thetimecertainlyseemedripeforabreakthroughin cancer.OnlylastmonthscientistsattheNationalCancerInstituteannounced thattheywerehaltingaclinicaltrialofadrugcalledtamoxifen他莫昔芬—and offeringittopatientsgettingtheplacebo安慰剂—becauseithadprovedso effectiveatpreventingbreastcanceralthoughitalsoseemedtoincreasethe riskofuterine子宫的cancer.TwoweekslatercametheNewYorkTimes’report thattwonewdrugscanshrinktumorsofeveryvarietywithoutanysideeffects whatsoever.??Itallseemedtoogoodtobetrueandofcourseit was.Therearenomiraclecancerdrugsatleastnotyet.Atthisstageallthe drugmanufacturercanofferissomeveryinterestingmoleculesandtheonly cancerstheyhavecuredsofarhavebeeninmice.BYthemiddleoflastweek eventheTVtalk-showhostswhotalkedmostaboutthenewshadlearnedwhat everyscientistalreadyknew:thatcuringadiseaseinlabanimalsisnotthe sameasdoingitinhumans.Thehistoryofcancerresearchhasbeenahistory ofcuringcancerinthemouseDr.RichardKlausnerheadoftheNational CancerInstitutetoldtheLosAngelesTimes.Wehavecuredmiceofcancerfor decades—anditsimplydidn’tworkinpeople.Inthefirstsentenceofthelastparagraphitwasmeans
TheCentralDogma ThoughitcomesasnosurprisethatthecompositionofDNAbetweendifferentorganismsisdifferentitisnotimmediatelyobviouswhythemusclecellsbloodcellsandbraincellsofanyoneparticularvertebrate脊椎动物aresodifferentintheirstructureandcompositionwhentheDNAofeveryoneoftheircellsisidentical.Thisisthekeytooneofthemostexcitingareasofmoderncellbiology.Indifferentcelltypesdifferentsetsofthetotalnumberofgenesgenome基因组areexpressed.InotherwordsdifferentregionsoftheDNAareactiveinthemusclecellsbloodcellsandbraincells. TounderstandhowthisdifferenceinDNAactivitycanleadtodifferencesincellstructureandcompositionitisnecessarytoconsiderwhatisoftenknownasthecentraldogma法则ofmolecularbiology:DNAmakesRNAmakeprotein.InmoleculartermsageneisthatportionofDNAthatencodesforasingleprotein.Thedictumonegenemakesoneproteinhasrequiredsomemodification改变withthediscoverythatsomeproteinsarecomposedofseveraldifferentpolypeptide多肽chainsbuttheonegenemakesonepolypeptideruledoeshold. DNAContainstheBlueprintforAllCellProteins. MessengerRNAisaprecisecopytranscriptofthecodedsequenceofnucleicacidbasesinDNAandthismessageistranslatedintoauniqueproteinmoleculeonspecialistorganellesribo-somespresentinthecytoplasm细胞质ofallcells.Proteins蛋白质whicharelargelymadeupofcarbonChydrogenHoxygenOandnitrogenNareconstructedfrom20differentcommonaminoacids.Theversatilityofproteinstheworkhorsemoleculesofthecellstemsfromtheimmensevarietyofmolecularshapesthatcanbecreatedbylinkingaminoacidstogetherindifferentsequences.Thesmallerproteinsconsistofonlyafewdozenaminoacidswhereasthelargeronesmaycontaininexcessof200aminoacidsalllinkedtogetherinalinear线状的chainbypeptidebonds. Astheproteinsarereleasedfromtheribosome核糖体theyfoldintouniqueshapesundertheinfluenceofchemicalforcesthatdependontheparticularsequenceofaminoacids.Sotheproteinprimarysequenceencodedinthegeneandfaithfullytranscribedandtranslatedintoanaminoacidchaindeterminesthethree-dimensionalstructureoftheemergingmolecule.Thehumanbodypossessessome30000differentkindsofproteinsandseveralmillioncopiesofmanyofthese.Eachplaysaspecificrole——forexamplehemoglobincarriesoxygeninthebloodactin肌动蛋白andmyosin肌球蛋白interacttogeneratemusclemovementandacetylcholine乙酸胆碱receptormoleculesmediatechemicaltransmissionbetweennerveandmusclecells. Enzymes—ProteinBiocatalysts Anessentialgroupofproteins—theenzymes酵素—actasbiologicalcatalysts催化剂andregulateallaspectsofcellmetabolism新陈代谢.Theyenablebreakdownofhigh-energyfoodmoleculescarbohydratestoprovideenergyforbiologicalreactionsandtheycontrolthesyntheticpathwaysthatresultinthegenerationoflipidse.g.fatscholesterol胆固醇andothervitalmembrane膜componentscarbohydrates碳水化合物sugarsstarch淀粉andcellulose纤维素thekeycomponentsofplantcellwallsandmanyvitalsmallbiomoleculesessentialforcellfunction. WhichofthefollowingStatementsaboutBiocatalystisfalse?
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