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请回答下列问题： （1）基因工程的核心是 ．其中的目的基因主要指编码 ，例如与生物抗逆性相关的基因等，也可以是一些具有调控作用的因子． （2）和这两个黏性末端能否连接在一起？ （填“...
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高三下学期生物《》真题及答案
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以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题运送目的基因进入受体细胞的载体一般
基因工程的基本操作程序主要包括四个步骤其中基因工程的核心是
目的基因的获取
基因表达载体的构建
将目的基因导入受体细胞
目的基因的检测与鉴定
如图是利用基因工程技术生产人胰岛素的操作过程示意图请回答下列问题1此图表示的是采取方法获取目的基因的
萤火虫发光是通过荧光素酶催化的系列反应所产生的现象科学家利用萤火虫的发光原理通过基因工程培育出一种能
根据基因工程的有关知识回答下列问题基因工程中除质粒外和也可作为运载体
依据基因工程技术和细胞工程有关原理回答下列问题获取目的基因途径有
以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题将人胰岛素基因分别导入大肠杆菌与酵
根据基因工程的有关知识回答下列问题按来源分基因工程使用的DNA连接酶有两类即
生物学家利用基因工程技术通过生物反应器生产人的血清蛋白请根据相关知识回答下列问题:每空1.5分1在基
科学家通过基因工程培育抗虫棉时需要从苏云金芽孢杆菌中提取出抗虫基因放入棉花的细胞中与棉花的DNA结合
请回答下列有关生物科技方面的问题利用基因工程可以获得转基因牛若要研制能够产生人类白细胞介素的牛乳腺生
根据基因工程的有关知识回答下列问题基因工程中除质粒外也可作为运载体
基因工程技术包括一系列的分子生物学操作步骤.请回答下列问题1基因工程操作的核心步骤是.2cDNA文库
以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题切割和连接DNA分子所使用的酶分别
以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题由于重组DNA分子成功导入受体细胞
依据基因工程技术和细胞工程有关原理回答下列问题基因工程操作的基本步骤是①②③④
以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题大肠杆菌是理想的受体细胞这是因为它
以重组DNA技术为核心的基因工程正在改变着人类的生活请回答下列问题获得目的基因的方法通常包括和
下图是治疗性克隆的过程图解请回答相关问题若该患者患有某种遗传性糖尿病可利用基因工程将正常胰岛素基因导
现代生物技术是
以细胞工程为核心的基因工程
以发酵工程和酶工程为核心的基因工程
以细胞工程为核心发酵工程和酶工程
以基因工程为核心的细胞工程
以基因工程为核心以及具备基因工程和细胞工程内涵的发酵工程和酶工程
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如图为速度选择器示意图P1P2为其两个极板．某带电粒子以速度v0从S1射入恰能沿虚线从S2射出．不计粒子重力下列说法正确的是
下列叙述中正确的是
某物理兴趣小组利用如图所示的电路给一个原来不带电的电容器充电在充电过程中电路中的电流为i电容器所带的电荷量为q两极板问的电势差为u电容器储存的能量为E电．下面的四幅示意图分别表示iqu和E电随时间t的变化关系其中可能正确的是
DT WhenBarbraStreisanddiscoveredin2003thataphotographofherCaliforniabeachhousewasamong12000photosontheInternetaspartofacollectionbyphotographerKennethAdelmanshedidwhatanyfamouspersonwoulddohithimwitha﹩50millionlawsuit.Butintryingtoholdbacktheimagesshecausedadifferentoutcome.Herlegalactionsledtoalmosthalfamillionpeoplevisitingthewebsiteviewingandcopyingthephotoswithinamonth. EversincethentheeffectoflettingpublicknowsomethingyouaretryingtokeepsecrethasbeencalledtheStreisandeffect.TheproblemforanyonetryingtosuppressinformationisthattheInternetistheworld'sbiggestandmostefficientcopyingmachine.Putadocumentontoaconnectedmachineanditwillspread.Sowhenyouwanttobefamousyoucan'tbutifyoufindyourselfinthespotlightandwanttoeraseyourselfyoucannot. ThereisnoshortageofexamplesoftheStreisandeffect.Nine﹣year﹣oldMarthaPaynecreatedasimpleblogpostingthemealsherschoolserved.Shetookaphotoofwhatwasbarelyafillingmealbyanyone'sstandards.WiththephotoshefilledacommentNowDadunderstandswhyIamhungrywhenIgethome.ThethingdidnotgotoofaruntilthelocalauthoritybannedlittleMarthafromdoingthatagain.MarthapostedasupposedlyfinalpostcalledGoodbyeexplainingeverything.Oncethemediafoundthisoutthingswentfrombadtoworsefortheauthority.Nowthebloghasmorethan9.5millionpageviews.MarthahasevenexpandedherblogbyincludingpicturesofschoolmealstakenbyotherkidsfromallovertheworldlikeGermanyandJapan. Wecanfindsimilarexamplesthroughouthistorytobefrank.ManhasexperiencedtheStreisandeffecteversincethebirthofmasscommunication.Whydoesitexist?Everytimeyouaretoldnottoseewhat'sinthesecretshinyboxwrappedingiftpaperyou'regoingtodoeverythinginyourpowertodoexactlythat!Justrealizingthatknowingsomethingaboutsomeoneisharmfultotheirstatuswewillwanttoknowthatpieceofinformation.Thisisexactlythehumannature.Thisiswhatlawyersandauthoritiesshouldbefamiliarwith.Unfortunatelyafewofthemfailtograspit. 1.TheunderlinedwordsuppressinParagraph2probablymeans. A.giveaway B.lookinto C.coverup D.searchfor 2.WhatspeededupthespreadofMartha'sstory? A.Parents'complaints. B.Theauthority'sorder. C.Thephotosofotherkids. D.Supportingfromtheschool. 3.Whatisthelastparagraphmainlyabout? A.TherootofStreisandeffect. B.TheinfluenceofStreisandeffect. C.People'sreactiontoStreisandeffect. D.HistoricalexamplesofStreisandeffect.
Morestudentsthaneverbeforearetakingagap﹣year间隔年beforegoingtouniversity.Itusedtobecalledtheyearoffbetweenschoolanduniversity.Thegap﹣yearphenomenonoriginated起源withthemonthsleftovertoOxbridgeapplicantsbetweenentranceexamsinNovemberandthestartofthenextacademicyear. Thisyear25310studentswhohaveacceptedplacesinhighereducationinstitutionshaveputofftheirentryuntilnextyearaccordingtostatisticsonuniversityentranceprovidedbyUniversityandCollegeAdmissionsSerbiceUCAS. Thatisarecord14.7%increaseinthenumberofstudentstakingagapyear.TonyHigginsfromUCASsaidthatthestatisticsaregoodnewsforeveryoneinhighereducation.Studentswhotakeawell﹣plannedyearoutaremorelikelytobesatisfiedwithandcompletetheirchosencourse.Studentswhotakeagapyearareoftenmorematureandresponsiblehesaid. Butnoteveryoneishappy.OwainJamesthepresidentoftheNationalUnionofStudentsNUSarguedthattheincreaseisevidenceofstudenthadship﹣youngpeoplearebeingforcedintoearningmoneybeforefinishingtheireducation.Newstudentsarenowawarethattheyarelikelytoleaveuniversityupto￡15000indebt.Itisnotsurprisingthatmoreandmorestudentsaretakingagapyeartoearnmoneytosupporttheirstudyforthedegree.NUSstatisticsshowthatover40%ofstudentsareforcedtoworkduringtermtimeandthefigureincreasesto90%duringvacationperiodshesaid. 29.Whatdowelearnaboutthegapyearfromthetext? A.Itisflexibleinlength. B.Itisatimeforrelaxation. C.Itisincreasinglypopular. D.Itisrequiredbyuniversities. 30.AccordingtoTonyHigginsstudentstakingagapyear. A.arcbetterpreparedforcollegestudies B.knowalotmoreabouttheirfuturejobs C.aremorelikelytoleaveuniversityindebt D.haveabetterchancetoentertopuniversities 31.HowdoesOwainJamesfeelaboutthegap﹣yearphenomenon? A.He'spuzzled. B.He'sworried. C.He'ssurprised. D.He'sannoyed. 32.WhatwouldmoststudentsdoontheirvacationaccordingtoNUSstatistics? A.Attendadditionalcourses. B.Makeplansforthenewterm. C.Earnmoneyfortheireducation. D.Preparefortheirgraduatestudies.
一定温度压强下在容积可变的密闭容器中发生反应COg+H2Og⇌CO2g+H2g△H＜0则下列说法不正确的是
6分 DT WhenBarbraStreisanddiscoveredin2003thataphotographofherCaliforniabeachhousewasamong12000photosontheInternetaspartofacollectionbyphotographerKennethAdelmanshedidwhatanyfamouspersonwoulddohithimwitha﹩50millionlawsuit.Butintryingtoholdbacktheimagesshecausedadifferentoutcome.Herlegalactionsledtoalmosthalfamillionpeoplevisitingthewebsiteviewingandcopyingthephotoswithinamonth. EversincethentheeffectoflettingpublicknowsomethingyouaretryingtokeepsecrethasbeencalledtheStreisandeffect.TheproblemforanyonetryingtosuppressinformationisthattheInternetistheworld'sbiggestandmostefficientcopyingmachine.Putadocumentontoaconnectedmachineanditwillspread.Sowhenyouwanttobefamousyoucan'tbutifyoufindyourselfinthespotlightandwanttoeraseyourselfyoucannot. ThereisnoshortageofexamplesoftheStreisandeffect.Nine﹣year﹣oldMarthaPaynecreatedasimpleblogpostingthemealsherschoolserved.Shetookaphotoofwhatwasbarelyafillingmealbyanyone'sstandards.WiththephotoshefilledacommentNowDadunderstandswhyIamhungrywhenIgethome.ThethingdidnotgotoofaruntilthelocalauthoritybannedlittleMarthafromdoingthatagain.MarthapostedasupposedlyfinalpostcalledGoodbyeexplainingeverything.Oncethemediafoundthisoutthingswentfrombadtoworsefortheauthority.Nowthebloghasmorethan9.5millionpageviews.MarthahasevenexpandedherblogbyincludingpicturesofschoolmealstakenbyotherkidsfromallovertheworldlikeGermanyandJapan. Wecanfindsimilarexamplesthroughouthistorytobefrank.ManhasexperiencedtheStreisandeffecteversincethebirthofmasscommunication.Whydoesitexist?Everytimeyouaretoldnottoseewhat'sinthesecretshinyboxwrappedingiftpaperyou'regoingtodoeverythinginyourpowertodoexactlythat!Justrealizingthatknowingsomethingaboutsomeoneisharmfultotheirstatuswewillwanttoknowthatpieceofinformation.Thisisexactlythehumannature.Thisiswhatlawyersandauthoritiesshouldbefamiliarwith.Unfortunatelyafewofthemfailtograspit. 1.TheunderlinedwordsuppressinParagraph2probablymeans. A.giveaway B.lookinto C.coverup D.searchfor 2.WhatspeededupthespreadofMartha'sstory? A.Parents'complaints. B.Theauthority'sorder. C.Thephotosofotherkids. D.Supportingfromtheschool. 3.Whatisthelastparagraphmainlyabout? A.TherootofStreisandeffect. B.TheinfluenceofStreisandeffect. C.People'sreactiontoStreisandeffect. D.HistoricalexamplesofStreisandeffect.
Vacationisatimeforrefreshment.Inworkweareoftencalledtothink.Sometimesit'sgoodtogiveourbrainsarest.Withoutabreakwemaynotbeabletoperformuptoourpotential.Thiscanbeaproblemnotonlyfortheemployeebutfortheemployeraswell. ThemainbenefitofvacationisfortheworkertocomebackenergizedsaysWeaver.Iftheyhaven'thadabreakthenthey'renotcomingbackwithnewenergy.Theyhaven'thadachancetostepbackandgetperspective远景andcomebackwithrenewedenthusiasm. Longworkinghourswithoutabreakinsecurity不安aboutone'sjobandotherwork﹣relatedworriescanleadtoburnoutandstress.Humanscanusuallyadapttopressurebutnotforalimitlessamountoftime. Itisaproblemofrelatinggoodworkersandhavingthemloyaltothefirmwhilethey'retheresaysDavidMaumePhDprofessorofsociologyattheUniversityofCincinnati.Hesaysburnoutcanalsoaffectemployees'productivitycreativityandeffectiveness. Inadditionhighlevelsofstressarelikelytobeprecursors前兆todepressionwhichcanhitboththeemployerandemployee'spocketbook.Evenpeoplewhomanagetoremainproductiveatworkcanhaveproblems.Ifthey'realwaysatworkthenthey'renotwiththeirfamilyandfriends.Ifthey'reworkingwhileonvacationforthetimethatthey'reonthejobthey'renotreallypresent. Anunbalancedemphasisonworkcanstrainfamilyandsociallife.Whenyoucomeupforairyoumayseethatyou'realoneorthatyourrelationshipshavegoneonwithoutyou. 1.What'sthemainbenefitofavacation? A.Themanagercanbemorecreative. B.Theworkercanstepbackandgetmoreexcited C.Theworkercancomebackwithnewenergy. D.Theworkercanadapttopressuremuchbetter. 2.Theunderlinedwordthereinthefourthparagraphprobablyrefersto. A.thevacation B.thehome C.theuniversity D.thecompany 3.Whenaworkerisalwaysatworkheislikelytogetmoreandmore. A.absent﹣minded B.energetic C.skillful D.active 4.Whichofthefollowingisthebesttitleofthetext? A.Howtospendthevacationeffectively. B.Whytheworkersneedavacation. C.Howtodealwiththedailypressure. D.Whytheworkersneednewenergy.
一个铀核U发生裂变核反应方程是U+n→Ba+K+3X并出现质量亏损．则
Theadobedwellings土坯房61buildbythePuebloIndiansoftheAmericanSouthwestareadmiredbyeven62mostmodernofarchitectsandengineers.Inadditiontotheirsimplebeautywhatmakestheadobedwellingsadmirableistheir63abletoairconditionahousewithout64useelectricequipment.Wallsmadeofadobetakeintheheatfromthesunonhotdaysandgiveoutthatheat65slowduringcoolnightsthuswarningthehouse.Whenanewdaybreaksthewallshavegivenuptheirheatandarenowcoldenough66coolthehouseduringthehotday67thesametimetheywarmupagainforthenightThiscycle68godayafterdayThewallswarmupduringthedayandcooloffduringthenightandthusalwaysatimelyoffset抵消fortheoutsidetemperatures.As69naturearchitectsthePuebloIndiansfiguredoutexactly70thicktheadobewallsneededtobetomakethecycleworkonmostdays. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.
Yourhousemayhaveaneffectonyourfigure.Expertssaythewayyoudesignyourhomecouldplayaroleinwhetheryoupackonthepoundsorkeepthemoff.Youcanmakeyourenvironmentworkforyouinsteadofagainstyou.Herearesomewaystoturnyourhomeintopartofdietplan. Openthecurtainsandturnupthelights.Darkenvironmentsaremorelikelytoencourageovereatingforpeopleareoftenlessself﹣consciouswhenthey'reinpoorlylitplaces﹣andsomorelikelytoeatlotsoffood.Ifyourhomedoesn'thaveenoughwindowlightgetmorelampsandfloodtheplacewithbrightness. Mindthecolors.Researchsuggestswarmcolorsfuelourappetites胃口.Inonestudypeoplewhoatemealsinablueroomconsumed消耗33percentlessthanthoseinayelloworredroom.Warmcolorslikeyellowmakefoodappearmoreappetizingwhilecoldcolorsmakeusfeellesshungry.Sowhenit'stimetorepaintgoblue. Don'tforgettheclock﹣﹣﹣ortheradio.Peoplewhoeatslowlytendtoconsumeabout70fewercalories卡路里permealthanthosewhorushthroughtheirmeals.Beginkeepingtrackofthetimeandtrytomakedinnerlastatleast30minutes.Andwhileyou'reatitactuallysitdowntoeat.Ifyouneedsomehelpslowingdownturnonrelaxingmusic.Itmakesyoulesslikelytorushthroughameal. Downsizethedishes.Bigservingbowlsandplatescaneasilymakeusfat.Weeatabout22percentmorewhenusinga12﹣inchplateinsteadofa10﹣inchplate.Whenwechoosealargespoonoverasmalleronetotalintake摄入jumpsby14percent.Andwe'llpourabout30percentmoreliquidintoashortwideglassthanatallskinnyglass. 1.Thetextisespeciallyhelpfulforthosewhocareabout. A.theirhomecomforts B.theirbodyshape C.housebuying D.healthydiets 2.Ahomeenvironmentinbluecanhelppeople. A.digestfoodbetter B.regaintheirappetites C.burnmorecalories D.reducefoodintake 3.Whatarepeopleadvisedtodoatmealtimes? A.Fatquickly. B.Playfastmusic. C.Usesmallerspoons. D.Turndownthelights. 4.Whatcanbeasuitabletitleforthetest? A.IsYourHouseMakingYouFat? B.WaysofServingDinner C.EffectsofSelf﹣Consciousness D.IsYourHomeEnvironmentRelaxing?
回答下列与生态系统相关的问题． 1在森林生态系统中生产者的能量来自于生产者的能量可以直接流向答出2点即可． 2通常对于一个水生生态系统来说可根据水体中含氧量的变化计算出生态系统中浮游植物的总初级生产量生产者所制造的有机物总量．若要测定某一水生生态系统中浮游植物的总初级生产量可在该水生生态系统中的某一水深处取水样将水样分成三等份一份直接测定O2含量A另两份分别装入不透光甲和透光乙的两个玻璃瓶中密闭后放回取样处若干小时后测定甲瓶中的O2含量B和乙瓶中的O2含量C．据此回答下列问题． 在甲乙瓶中生产者呼吸作用相同且瓶中只有生产者的条件下本实验中C与A的差值表示这段时间内C与B的差值表示这段时间内A与B的差值表示这段时间内．
下列根据实验操作和现象所得出的结论正确的是
运用化学反应原理研究NH3的性质具有重要意义．1科学家一直致力于人工固氮的新方法研究．据报道在光照条件下N2在催化剂表面与水发生反应生成NH3和另一种单质．在使用催化剂和不使用催化剂时该反应过程和能量的变化关系如图所示．①写出该反应的化学方程式．②a和b相比二者的平衡常数关系是KaKb填＞＝或＜．③升高温度平衡时NH3的含量填增大不变或减小．2在0.5L的密闭容器中一定量的N2和H2发生反应N2g+3H2g⇌2NH3g△H＜0400℃时K＝0.5某一时刻测得N2H2和NH3三种物质物质的量分别为2mol2mol和3mol则该反应的v正N2v逆N2填＞＝或＜．3将NH3气体通入稀盐酸中若存在[NH4+]＞[Cl﹣]＞[OH﹣]＞[H+]的关系此时所得溶液的溶质是填化学式．4NH3的催化氧化反应是工业制HNO3的关键步骤测得某温度下固定容积的容器中的数据为①则2～4min内vO2＝．②在第8min时改变条件你认为改变的条件可能是．
如图所示用半径相同的AB两球的碰撞可以验证“动量守恒定律”．实验时先让质量为m1的A球从斜槽轨道上某一固定位置S由静止开始滚下从轨道末端抛出落到位于水平地面的复写纸上在下面的白纸上留下痕迹．重复上述操作10次得到10个落点痕迹．再把质量为m2的B球放在斜槽轨道末端让A球仍从位置S由静止滚下与B球碰撞后分别在白纸上留下各自的落点痕迹重复操作10次．MPN为三个落点的平均位置． ①实验中直接测定小球碰撞前后的速度是不容易的．但是可以通过测量间接地解决这个问题． A．小球开始释放高度hB．小球抛出点距地面的高度HC．小球做平抛运动的射程 ②以下提供的测量工具中本实验必须使用的是多选． A．刻度尺B．天平C．游标卡尺D．秒表 ③关于本实验下列说法正确的是． A．斜槽轨道必须光滑B．斜槽轨道末端必须水平C．实验过程中复写纸和白纸都可以移动 ④在实验误差允许范围内若满足关系式则可以认为两球碰撞前后总动量守恒． A．m1．OP＝m1．OM+m2•ONB．mc．OP＝m1．ON+m2．OM C．m1．OM＝m1．OP+m2．OND．m1．ON＝ml．OP+m2．OM ⑤在实验中为了让A球碰后沿原方向运动应满足A球的质量m1大于B球的质量m2请推理说明．
如图所示一理想变压器的原线圈接正弦交流电源副线圈接有电阻R和小灯泡．电流表和电压表均可视为理想电表．闭合开关S下列说法正确的是
光子除了有能量还有动量．若光子能量为E动量为J则光子动量p＝式中c为真空中的光速．当光照射到物体表面上时不论光被物体吸收还是被物体表面反射光子的动量都会发生改变因而对物体表面产生一种压力． 如图是1901年俄同物理学家列别捷夫测量光压的实验装置．T型架通过悬丝竖直悬挂横臂水平悬丝一端同定在横臂中点．在横臂的两侧有圆片P和Q两圆片与T型架在同一竖直平面内．圆片P是涂黑的当光线照射到P上时可以认为光子全部被吸收圆片Q是光亮的当光线照射到Q上时可以认为光子全部被反射．分别将光线照射在P或Q上都可以引起悬丝的旋转．在悬丝上固定一__面M用一细光束照射时就可以获知悬丝扭转的角度．已知光速为c两个圆片PQ的半径都为r．悬丝转过的角度与光对网片的压力成正比． a．用光强单位时间内通过与传播方向垂直的单位面积的光能为I0的激光束垂直照射整个圆片P求激光束对圆片P的压力F2的大小 b．实验中第一次用光强厶为的激光束单独照射整个圆片P平衡时光束与圆片垂直且悬丝有一扭转角第二次仍用该光束单独照射整个圆片Q平衡时光束与圆片不垂直悬丝的扭转角与第一次相同．求激光束与圆片Q所在平面的夹角φ．
Mycolortelevisionhasgivenmenothingbutaheadache.IwasabletobuyitalittleoverayearagobecauseIhadmyrelativesgivememoneyformybirthdayinsteadofalotofclothesthatwouldn'tfit.IletasalesclerkfoolmeintobuyingadiscontinuedmodelIrealizedthisadaylatewhenIsawnewspaperadvertisementsforthesetatseventy﹣fivedollarslessthanIhadpaidThesetworkedsobeautifullywhenIfirstgotithomethatIwouldkeepitonuntilstationssignedoffforthenightFortunatelyIdidn'tgotanychannelsshowingall﹣nightmoviesorIwouldneverhavegottentobed. ThenIstarteddevelopingaproblemwiththesetthatinvolvedstatic静电noise.Forsomereasonwhencertainshowsswitchedintoacommercialaloudnoisewouldsoundforafewseconds.GraduallythisnoisebegantoappearduringashowandtogetridofitIhadtochangetoanotherchannelandthenchangeitback.SometimesthistechniquewouldnotworkandIhadtopickupthesetandshakeittoremovethesound.Iactuallybegantobuildupmyarmmuscles肌肉shakingmyset. WhenneitherofthesemethodsremovedthestaticnoiseIwouldsithelplesslyandwaitforthenoisetogoaway.AtlastIendeduphittingthesetwithmyfistanditstoppedworkingaltogether.Mytriptotherepairshopcostme$62andthesetisworkingwellnowbutIkeepexpectingmoretrouble. 21.WhydidtheauthorsayhewasfooledintobuyingtheTVset? A.Hegotanoldermodelthanhehadexpected. B.Hecouldn'treturnitwhenitwasbroken. C.Hecouldhaveboughtitatalowerprice. D.Hefailedtofindanymovieshowsonit. 22.WhichofthefollowingcanbestreplacethephrasesignedoffinParagraph1? A.endedalltheirprograms B.providedfewerchannels C.changedtocommercials D.showedall﹣nightmovies 23.HowdidtheauthorfinallygethisTVsetworkingagain? A.Byshakingandhittingit. B.Byturningitonandoff. C.Byswitchingchannels. D.Byhavingitrepaired. 24.Howdoestheauthorsoundwhentellingthestory? A.Curious B.Anxious C.Cautious D.Humorous.
如图为香芹酮分子的结构下列有关叙述正确的是
工业上利用锌焙砂主要含ZnOZnFe2O4还含有少量FeOCuO等氧化物杂质制取金属锌的流程如图甲所示．1提高酸浸效率的措施为任答一条即可酸浸时H+与难溶固体ZnFe2O4反应的离子方程式为．2净化Ⅰ中H2O2参与反应的离子方程式为X可选择的试剂为写化学式净化Ⅱ中Y为写化学式3电解法制备锌的装置如图乙所示则电解槽中盛有的电解质溶液为填字母a．ZnCl2溶液b．ZnNO32溶液c．ZnSO4溶液根据图乙中的数据可求得电解过程中电流的有效利用率为4使用含有[ZnOH4]2﹣的强碱性电镀液进行镀锌防腐蚀可得到细致的光滑镀层电镀时阴极电极反应式以锌为负极采用牺牲阳极法防止铁闸的腐蚀图丙中锌块的固定位置最好应在处填字母．
解热镇痛药贝诺酯的合成路线如下 请回答下列问题 1A→B的反应类型为B→E的另一产物是． 2X是水杨酸的同分异构体X中含有苯环属于酯类遇FeCl3溶液显紫色．则X的结构简式为任写一种． 3F中官能团的名称为．1mol扑热息痛与足量NaOH溶液反应消耗NaOH的物质的量为． 4生成贝诺酯的化学方程式为．
下列关于有机物的说法正确的是
直流电动机的基本结构由永磁铁和矩形线圈构成如图1所示．现将标有“3V3W”的直流电动机串联一个滑动变阻器接在电动势为E＝4.0V内阻为r＝0.40Ω的电源的两端如图2所示．已知电动机线圈的电阻R0＝0.10Ω不计其它电阻． 1若滑动变阻器接入电路的阻值R1＝3.5Ω且电动机卡住不转求此时电路中的电流I1． 2调节滑动变阻器接入电路的阻值或电动机工作时的负载发生变化回路中的电流I及电源的输出功率P随之改变． a．请从理论上推导P与I的关系式并在图3中定性画出P﹣I图象 b．求该电源对外电路能够输出的最大功率Pm． 3调节滑动变阻器接入电路的阻值使电动机正常工作．现保持滑动变阻器接入电路的阻值不变增加电动机的负载电动机将通过转速调节达到新的稳定状态．请分析说明在这个过程中电路中的电流如何变化．
NA表示阿伏加德罗常数的值下列说法正确的是
常温下向20.00mL0.1000mol•L﹣1NH42SO4溶液中逐滴加入0.2000mol•L﹣1NaOH溶液时溶液的pH与所加NaOH溶液体积的关系如图所示不考虑NH3•H2O的分解．下列说法不正确的是
物质W是一种含氮有机物会污染土壤．W在培养基中达到一定量时培养基表现为不透明．某研究小组欲从土壤中筛选出能降解W的细菌目标菌．回答下列问题． 1要从土壤中分离目标菌所用选择培养基中的氮源应该是． 2在从土壤中分离目标菌的过程中发现培养基上甲乙两种细菌都能生长并形成菌落如图所示．如果要得到目标菌应该选择菌落进一步纯化．选择的依据是． 3土壤中的某些微生物可以利用空气中的氮气作为氮源若要设计实验进一步确定甲乙菌能否利用空气中的氮气作为氮源请简要写出实验思路预期结果和结论即． 4该小组将人工合成的一段DNA转入大肠杆菌使大肠杆菌产生能降解W的酶酶E．为了比较酶E与天然酶降解W能力的差异该小组拟进行如下实验请完善相关内容． ①在含有一定浓度W的固体培养基上A处滴加含有酶E的缓冲液B处滴加含有相同浓度天然酶的缓冲液C处滴加三处滴加量相同． ②一段时间后测量透明圈的直径．若C处没有出现透明圈说明若AB处形成的透明圈直径大小相近说明．
Theadobedwellings土坯房61buildbythePuebloIndiansoftheAmericanSouthwestareadmiredbyeven62mostmodernofarchitectsandengineers.Inadditiontotheirsimplebeautywhatmakestheadobedwellingsadmirableistheir63abletoairconditionahousewithout64useelectricequipment.Wallsmadeofadobetakeintheheatfromthesunonhotdaysandgiveoutthatheat65slowduringcoolnightsthuswarningthehouse.Whenanewdaybreaksthewallshavegivenuptheirheatandarenowcoldenough66coolthehouseduringthehotday67thesametimetheywarmupagainforthenightThiscycle68godayafterdayThewallswarmupduringthedayandcooloffduringthenightandthusalwaysatimelyoffset抵消fortheoutsidetemperatures.As69naturearchitectsthePuebloIndiansfiguredoutexactly70thicktheadobewallsneededtobetomakethecycleworkonmostdays. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.
铝生产产业链由铝土矿开采氧化铝制取铝的冶炼和铝材加工等环节构成． 1工业上采用电解氧化铝和冰晶石Na3AlF6熔融体的方法冶炼得到金属铝 2Al2O34Al+3O2↑．加入冰晶石的作用为． 2上述工艺所得铝材中往往含有少量Fe和Si等杂质可用电解方法进一步提纯该电解池中阳极的电极 反应式为下列可作阴极材料的是． a．铝材b．石墨c．铅板d．纯铝 3阳极氧化能使金属表面生成致密的氧化膜．以稀硫酸为电解液铝阳极发生的电极反应式为．在铝阳极氧化过程中需要不断地调整电压理由是． 4下列说法正确的是． a．阳极氧化是应用原电池原理进行金属材料表面处理的技术 b．铝的阳极氧化可增强铝表面的绝缘性能 c．铝的阳极氧化可提高金属铝及其合金的耐腐蚀性但耐磨性下降 d．铝的阳极氧化膜富多孔性具有很强的吸附性能能吸附染料而呈各种颜色．
AsakidIlovedeverythingaboutschool.Ilovedbooks1testsandhomework.MostofallIlongedtosomedaymarchdowntheaisle通道toreceivemy2.Thatseemedmoreappealingeventhangettingmarried.Butat15Ihadto3becausemyparents4affordtuition学费.Myhopeofgettingadiplomawasdead. PrettysoonImarried.IhadthreeChildrenandIthoughtThere5mydiploma.EvensoIwantedmychildrentobeeducated.ButLindaouryoungestchildhadjuvenilearthritis幼年型关节炎inher6andkneeswhichmadeit7forhertofunctioninanormalclassroom. OnedayIsawanadinthenewspaperforeveningcourses. That'stheanswerIsaidtomyself.Lindaalwaysfeels8intheeveningsoI'lljustsignherupfornightschool. Lindawasbusy9outenrollment入学formswhenthesecretarysaidMrsSchantzwhydon'tyoucomebackto10? I11There'snoway!I'm! 12heinsistedandbeforeIknewwhatIhaddoneIwasenrolledforclassesinEnglishandcrafts.ThisisonlyanexperimentI13himbuthejustsmiled.TomysurprisebothLindaandIthrived茁壮成长ineveningschool.Iwentbackagainthenextsemesterandmygrades14improved. Itwas15togotoschoolagainbutitwasnogame.Sittinginaclassfullofkidswasawkward16mostofthemwererespectfulandencouraging.DuringthedayIstillhadloadsofhouseworktodo.ButwhenIwasdownLindaencouragedme.Mumyoucan't17now!AndwhenshewasdownI18her.Togetherwesawitthrough.AtlastIgotmydiploma.19myclassmatesvotedunanimously一致地formetobeclassspeakerandIgota$3000collegescholarship. YesMumIwaslateforschoolbutIgotthere20. 1.A.parents B.teachers C.trees D.flowers 2.A.job B.present C.certification D.diploma 3.A.dropout B.watchout C.keepout D.findout 4.A.wouldn't B.couldn't C.shouldn't D.needn't 5.A.goes B.comes C.exists D.breaks 6.A.hands B.head C.eyes D.stomach 7.A.1ikely B.frequent C.easy D.impossible 8.A.Worse B.excited C.better D.annoyed 9.A.giving B.taking C.filling D.sending 10.A.work B.school C.home D.office 11.A.laughed B.told C.argued D.shouted 12.A.And B.But C.Although D.So 13.A.informed B.asked C.warned D.convinced 14.A.regularly B.happily C.steadily D.naturally 【考点】记叙文人生感悟类阅读 【分析】文章讲述了作者小时候很喜欢上学因为父母负担不起学费而辍学.她55岁时和女儿一起上夜校并获得了大学奖学金最终实现了自己小时候的梦想. 【解答】C副词辨析.regularly有规律地happily开心地steadily稳定地natumlly自然地.我的成绩稳步提高.故选C. 【点评】完型填空题的命题趋势 【备注】1#1#1#C ~15.A.interesting B.disappointing C.concerned D.exciting 16.A.asif B.evenif C.incase D.ifonly 17.A.continue B.rest C.quit D.hesitate 18.A.raised B.discouraged C.cheered D.defeated 19.A.Tomysurprise B.Tomysatisfaction C.Tomyrelief D.Tomycredit 20.A.naturally B.frequently C.constantly D.eventually
Trainingforamarathonrequirescarefulpreparationandsteadygradualincreasesinthelengthoftheruns.36buythebest﹣fittingbest﹣builtrunningshoesyoucanfind.Noonecansaywhichbrandwillworkbestforyouorfeelbestonyourfeetsoyouhavetorelyonyourexperienceandonthefeelofeachpairasyoushop.Whenyouhavefoundshoesthatseemrightwalkinthemforafewdaystodouble﹣checkthefit.37.Asalwaysyoushouldstretch伸展atleasttenminutesbeforeeachruntopreventinjuries. Duringthefirstweekdonotthinkaboutdistancebutrunfiveminuteslongereachday.38itiswisetotakeadayofftorest.Butduringthenextweeksetagoalofatleastamileandahalfperrun.39.Aftertwoweeksstarttimingyourself.40.Dependingonthekindofraceyouplantoenteryoucansetupatimetablefortheremainingweeksbeforetherace. A.Aftersixdays B.Foragoodmarathonrunner C.Beforeyoubeginyourtraining D.Witheachdayincreasethedistancebyahalfmile E.Iftheystillfeelgoodyoucanbeginrunninginthem F.Timespentforpreparationraisesthequalityoftraining G.Nowyouarereadytofigureoutagoalofimprovingdistanceandtime. 36. 37. 38. 39. 40.
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