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为研究叶面施肥对花生光合作用的影响，科研人员用适宜浓度的氮肥（尿素）、磷肥（过磷酸钙）和钾肥（硫酸钾）分别喷施于长势相冋的花生叶片进行实验，结果见下表．回答下列问题． （1）在花生叶肉细胞中，叶...
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高三下学期生物《》真题及答案
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合理施肥的实质是提高了光能的利用率下列叙述与提高光合作用效率密切相关的是①氮使叶面积增大增大了光合面
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回答下列有关光合作用的问题右表为某地夏季晴朗的某天玉米和花生净光合速率测定值下图表示玉米CO2同化途
合理施肥的实质是提高了光能的利用率下列叙述与提高光合作用效率密切相关的是①氮使叶面积增大增大了光合面
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科研人员为研究氧气浓度与光合作用的关系测定了烟草叶片在25℃时不同氧气浓度下的光合作用速率以CO2的
某科研小组的科研人员利用不同的植物分别做了有关光合作用的两组实验请结合实验过程和结果分析回答问题实验
甲乙两图是农业科研人员在进行研究时绘制的其中图甲表示某农作物的光合作用速率与光照强度之间的关系CO2
回答下列有关光合作用的问题右表为某地夏季晴朗的某天玉米和花生净光合速率测定值下图表示玉米CO2同化途
2015•湖州为了解低温对玉米牛长快慢的影响科研人员进行了实验研究从甲乙丙三个品种中挑选长势相同的玉
如图表示叶片面积指数与光合产物实际量呼吸量等的关系叶面积指数是指植物单位面积中叶面积的数量此数量越大
光合作用实际量、呼吸作用量、干物质量；植物的净光合作用等于零
光合作用实际量、干物质量、呼吸作用量；植物的净光合作用等于零
干物质量、光合作用实际量、呼吸作用量；植物的净光合作用大于零
呼吸作用量、光合作用实际量、干物质量；植物的净光合作用小于零
为研究叶面施肥对大豆植株光合作用的影响科研人员用适宜浓度的氮肥尿素钾肥硫酸钾磷肥过磷酸钙和硼肥硼酸
合理施肥的实质是提高了光能的利用率下列叙述与提高光合作用效率密切相关的是①镁使叶面积增大增大了光合面
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某科研小组的科研人员利用不同的植物分别做了有关光合作用的两组实验请结合实验过程和结果分析回答问题实验
叶面施肥有好处
叶面喷施氮、磷肥，能加强叶片的光合作用和根活力
叶面施肥能较快为植物吸收
叶面施肥在量上容易掌握，可与杀虫剂同喷，因而可减低费用。
叶面施肥可避免肥料进入土壤被固定转化
请回答下列有关光合作用的问题光合作用受到温度二氧化碳浓度和光照强度的影响其中光照强度直接影响光合作用
科研人员研究了土壤含水量对番茄品种甲和乙光合作用的影响请回答问题⑴据图1分析比较甲乙两种番茄土壤含水
为研究叶面施肥对大豆植株光合作用的影响科研人员用适宜浓度的氮肥尿素钾肥硫酸钾磷肥过磷酸钙和硼肥硼酸
自然界中和花生相比玉米更适合生长在高温光照强烈和干旱的环境其利用低浓度CO2的能力也远远高于花生某科
为研究叶面施肥对花生光合作用的影响科研人员用适宜浓度的氮肥尿素磷肥过磷酸钙和钾肥硫酸钾分别喷施于长
甲乙两图是农业科研人员在进行研究时绘制的其中图甲表示某农作物的光合作用速率与光照强度之间的关系CO2
叶面施肥效果好所以应加大对叶面施肥减 少或不进行地下施肥
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Whydowedream?It'saquestionresearchershavebeenstudyingforyears.Nownewresearchsuggeststhatsomedreamsmayresultfromthebrain'sefforttokeeplearningevenaswesleep. InastudyinBoston100volunteersweretrainedforanhouronamaze迷宫.Theytriedtofindtheirwaythroughthedifficultpuzzleasquicklyaspossible.Thenhalfofthevolunteerswereallowedtosleepfor90minutes.Theotherhalfstayedawakereadingorrelaxing.Theoneswhosleptwereaskedtodescribetheirdreamswhentheywokeup. Aftertherestthevolunteerswereaskedagaintosolvethemaze.Thosewhohadn'tsleptshowednoimprovementordidevenworseafterthebreak.Sleeperswhodidn'treportanymazerelateddreamsdidbetterbutshowedonlyalittleimprovement.Howeverfournaptakerswhoreporteddreamingaboutthemazeshowedasurprisingimprovement.Theyscored10timeshigheraftersleepinganddreamingaboutthemaze. Eventhoughthenumberofdreamerswassmalltheresearchersnotedthatthegapinlearningbetweenthedreamersandnondreamerswassowidethatthefindingwassignificant有意义的. Thedreamershadallperformedpoorlyonthetestbeforedreamingaboutit.Thatsuggeststhatstrugglingwithataskmightbethetriggerthatleadsthesleepingbraintofocusonitandworkonhowtodealwithit. It'salmostasifyourbrainisgoingthrougheverythingthathappenedtodayDrStickgoldascientistatHarvardMedicalSchoolsaid.Thethingsyou'reobsessed迷住witharetheonesthatyourbrainforcesyoutocontinuetodowith. 1Whatwerethevolunteersaskedtodoaftertherest? A.Toworkonanewmaze. B.Tocontinuetodothemaze. C.Totalkwitheachotherabouttheirdreams. D.Totellwhattheythoughtaboutthemaze. 2Accordingtothestudywhichgroupshowedthegreatestimprovement? A.Thosewhodidn'tsleep. B.Thosewhosleptbutdidn'tdream. C.Thosewhodreamedaboutthemazewhilesleeping. D.Thosewhothoughtaboutthemazebeforefallingasleep. 3TheunderlinedwordtriggerinParagraph5probablymeans. A.chance B.cause C.way D.idea 4What'sthebesttitleforthispassage? A.LearningWhileYouDream B.WhatDreamsStandfor C.DreamaGoodDream D.DreamsandHealth
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FourHabitstoHelpYouSucceed Weallwanttosucceed.Forthosewhohavetriedandfailedsuccessseemsdifficulttounderstand.1. •Knowyourvalues. Findingyourvaluesisinlinewithcreatingmotivation.2Pickahandfulofthingsandwritethemdown.Remindyourselfofyourvalueseverydayandreflectonwhetheryouarehonoringthosevaluesthroughyourwork. •Pickagoalandfocusonit. Chooseonegoaltostartsomethinglargeenoughthatwillgiveyouasenseofachievementwhileadjustingwelltoyourvalues.Focusiskeyhere.3Ifyouperformmanytasksatatimeyoumightneverfinishyourprojectsbecausetheywilltakefartoolong. •Setatimeforsuccess. Setadateforsuccess.Knowwhenyouhopetorealizeyourgoal.4Bysettingatimelimityouaremakingtheprocessrealistic. •5. Failurecan'tbeavoidedwhenyoutakerisks.Byitsverydefinitionthedesiretosucceedmeansyouareriskingfailure.Manypeopletendtogiveupfartooearly.Don'tfallintothistrap!Usefailure.Treatitasagoodthingandgoon. A.Themorefocusedyouareononegoalthehigherchanceyouhaveofsuccess. B.Maketherightdecision. C.Ihavemadealistoffourhabitstohelpyousetgoalsandrealizethem. D.Don'tgiveupbecauseoffailure. E.Keepitrealisticwhilenotgivingyoutoomuchtime. F.Sitandreflectonwhatyouvaluemost. G.Pushyourselftobecourageousandtakethatnextstep.
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处每处错误仅涉及一个单词的增加删除或修改. 增加把缺词处加个漏字符号∧并在其下面写出该加的词. 删除把多余的词用斜线\划掉.修改在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改均仅限一词 2.只允许修改10处多者从第11处起不计分. Todaythenumberofthenetizens网民inourcountryhaveincreasedrapidlyyetmanyofthemdonotpayenoughattentiontothefamily.ItisnodoubtthatwebenefitmuchfromtheInternet.Foranexampleit'sconvenientforustogettheinformationsweneedandcommunicatewithourfriendsandrelatives.Meanwhileitcouldhelpuslearnthatishappeningbothathomeandabroad.ThereforenomatterhowattractivetheInternetisweshouldn'tseparatedfromourlovedones.WeshouldstopsurftheInternetandspendtimewithourfamiliesenjoyingthetimewhenyouaretogether.
如图是用动滑轮提升货物A的示意图．在竖直向上的拉力F的作用下使重400N的货物A在50s的时间里匀速竖直上升了10m．在这个过程中拉力F为250N不计绳重及摩擦．求 1动滑轮重G动2动滑轮的机械效率η3拉力F的功率P．
TomarrivedatthebusstationquiteearlyfortheLondonbus.ThebusforLondonwouldnotleaveuntilfivetotwelve.Hesawalotofpeoplewaitinginthestation.Somewerestandinginlinesandotherswerewalkingabout.Therewasagroupofschoolgirls.Theirteacherwascryingtokeeptheminorder.Tomlookedaroundbuttherewasnowhereforhimtosit. Hewalkedintothestationcafé.Helookedupattheclockthere.Itwasonlytwentytotwelve.Hefoundaseatandsatdownfacingalargemirroronthewall.JustthenJohnoneofTom'sfriendscameinandsatwithTom. Whattimeisyourbus?askedJohn. OhthereisplentyoftimeyetansweredTom. OhI'llgetyousomemoreteathensaidJohn. Theytalkedwhiledrinking.ThenTomlookedattheclockagain. Goodheavens!It'sgoingback﹣ward!hecried.Afewminutesagoitwastwentytotwelveandnowit'shalfpasteleven. YouarelookingattheclockinthemirrorsaidJohn. Tomwantedtokickhimselfforbeingsofoolish.Thenextbuswasnottoleaveforanotherhour.Hehasneverlikemirrorsincethen. 1TheLondonbusleft. A.at1155 B.at512 C.before1155 D.after1155 2Tomwentintothestationcafébecause. A.Johnaskedhimtohaveacupoftea B.hewantedadrinkthere C.hewouldmeetafriendofhis D.itwasearlyyetandhewantedtofindaplacetosit 3Whattimewasitinfactwhenhelookedattheclockinthemirror? A.Halfpasttwelve. B.Halfpasteleven. C.Twentytotwelve. D.Halfpastone. 4Whichofthefollowingistrue? A.Tommissedhisbus B.Hehaslikemirrorsincethen. C.Thenextbuswouldleavesoon. D.TomarrivedLondonontime.
小明在老师的指导下用小球和弹簧等器材进行了如下实验与探究不考虑空气阻力让小球从某高度处由静止开始下落到竖直放置的轻弹簧上如图甲在刚接触轻弹簧的瞬间如图乙小球速度为5.0m/s．从小球接触弹簧到将弹簧压缩至最短如图丙的整个过程中得到小球的速度v和弹簧缩短的长度△x之间的关系如图丁所示其中A为曲线的最高点已知该轻弹簧每受到0.1N的压力就缩短0.5cm并且轻弹簧在全过程中始终发生弹性形变． 1从小球接触弹簧到将弹簧压缩至最短的过程中小球速度的变化情况是 2当小球的速度为5.0m/s时弹簧产生的弹力F与小球的重力G的关系为FG大于/小于/等于当弹簧的压缩量最大时小球处于平衡/非平衡态． 3实验中所用小球的质量为kg全过程中弹簧中弹力的最大值为N．
如图是珠海航空展飞行表演时的情景以为参照物飞机是运动的飞机向后喷气却能向前飞行这是因为歼20战机飞行速度最大可达850m/s则30min内歼20最大飞行距离可达km．
如图所示是某家用电器的内部电路图其中R1和R2为加热电阻1234分别为四个接线柱．若要让两电阻串联接入电路则将接线柱与接线柱3连接此电路中不能将接线柱与接线柱3相连否则造成短路．电功率最大的连接方法是将接线柱1和3连接同时将接线柱连接起来．
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