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某品系果蝇的2号染色体上有A、a和B、b两对等位基因（如图所示），A对a显性，B对b显性，A或B纯合都致死，且A基因所在一大片段发生倒位，抑制2号染色体间的非姐妹染色单体发生交换，该品系称为平衡致死...
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高三下学期生物《》真题及答案
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.下列关于自由组合规律遗传实验叙述中错误的是
两对相对性状分别由两对等位基因控制
两对等位基因位于一对同源染色体上
每一对等位基因的传递都遵循分离规律
F
2
中有9种基因型和4种表现型
27.13分如图为果蝇体细胞染色体及部分基因位置的示意图请回答下列问题1果蝇的体细胞内有______
现有翅型为裂翅的果蝇新品系裂翅
对非裂翅(a)为显性。实验得知，等位基因(A.a)与(D.d)位于同一对常染色体上，基因型为AA或dd的个体胚胎致死。两对等位基因功能互不影响，且在减数分裂过程中不发生交叉互换。这两对等位基因的遗传是否遵循自由组合定律？以基因型为如图所示的裂翅果蝇为亲本，逐代自由交配，则后代中基因A.的频率将如何改变( )
A.遵循 不变
不遵循 上升
遵循 下降
不遵循 不变
现有翅型为裂翅的果蝇新品系裂翅A.对非裂翅a为显性杂交实验如图l请回答1上述亲本中裂翅果蝇为纯合子／
已知果蝇的长翅和残翅性状是由位于第Ⅱ号同源染色体常染色体上的一对等位基因控制现有一批未交配过的纯种长
10分 已知果蝇长翅和小翅红眼和棕眼各为一对相对性状分别受一对等位基因控制且两对等位基因位于不同的
1某精原细胞含有两对等位基因AaBb分别位于两对同源染色体上经减数分裂该精原细胞共产生_______
下列遵循基因的自由组合定律的是
一对同源染色体相同位置上的等位基因
两对同源染色体上的两对等位基因
姐妹染色单体相同位置上的两个基因
同一条染色体上的两个或多个基因
现有翅型为裂翅的果蝇新品系裂翅A.对非裂翅a为显性.杂交实验如图1.请回答1上述亲本中裂翅果蝇为纯合
右图中为果蝇某条染色体上部分基因的分布图下列有关说法错误的是
一条染色体上有多个基因
基因在染色体上呈线性排列
图中的白眼基因和朱红眼基因可称为一对等位基因
果蝇细胞内的基因并非全都分布在染色体上
10分 已知果蝇长翅和小翅红眼和棕眼各为一对相对性状分别受一对等位基因控制且两对等位基因位于不同的
31.现有翅型为裂翅的果蝇新品系裂翅A.对非裂翅a为显性杂交实验如图11上述亲本中裂翅果蝇为____
27.13分如图为果蝇体细胞染色体及部分基因位置的示意图请回答下列问题1果蝇的体细胞内有______
Aa和Bb是控制两对相对性状的两对等位基因位于1号和2号这一对同源染色体上1号染色体上有部分来自其他
A和a、B和b均符合基因的分离定律
可以通过显微镜来观察这种染色体移接现象
染色体片段移接到1号染色体上的现象称为基因重组
同源染色体上非姐妹染色单体发生交叉互换后可能产生4种配子
11.下列关于孟德尔遗传定律解释的叙述错误的是
非同源染色体上的非等位基因的分离或组合是互不干扰的
同源染色体上的一对等位基因各自独立，互不混杂
同源染色体上的等位基因分离，非等位基因自由组合
控制两对相对性状的等位基因分别位于两对同源染色体上
27.13分如图为果蝇体细胞染色体及部分基因位置的示意图请回答下列问题1果蝇的体细胞内有______
已知某种昆虫的有眼A.与无眼a正常刚毛B.与小刚毛b正常翅E.与斑翅e这三对相对性状各受一对等位基因
3.2012·福建理综现有翅型为裂翅的果蝇新品系裂翅A.对非裂翅a为显性杂交实验如图1请回答1上述亲
现有翅型为裂翅的果蝇新品系裂翅A.对非裂翅a为显性杂交实验如图11上述亲本中裂翅果蝇为_______
10分 已知果蝇长翅和小翅红眼和棕眼各为一对相对性状分别受一对等位基因控制且两对等位基因位于不同的
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﹣﹣﹣There'refourbedroomsinthehousewithitsownshower. ﹣﹣﹣That'swhatIwant.I'vegotafewkids. A.either B.neither C.each D.none
﹣ExcusemeJohnbutwhichisforme? ﹣Youcantakehalf.Theyareexactlythesame. A.either B.both C.any D.neither
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.
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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
100克盐放入700克水中盐占盐水的%．
IneversawmyfatherhomefromworklateorillnordidIeverseemyfathertakeanightoutwiththeboys.Hehadnobobbiesbutjusttookcareofhisfamily. For22yearssinceIlefthomeforcollegemyfathercalledmeeverySundayat900am.Hewasalwaysinterestedinmylife﹣howmyfamilywasdoing.ThecallsevencamewhenheandmymotherwereinAustraliaEnglandorFlorida. NineyearsagowhenIboughtmefirsthousemyfather67yearsoldspenteighthoursadayforthreedayspaintingmyhouse.Hewouldnotallowmetopaysomeonetohaveitdone.AllheaskedwasaglassoficedteaandthatIholdapaintbrushforhimandtalktohim.ButIwastoobusyforIhadalawpracticetorunandIcouldnottakethetimetoholdthepaintbrushortalktomyfather. Fiveyearsagomy71﹣year﹣oldfatherspentfivehoursputtingtogetheraswingset秋千formydaughter.AgainallheaskedwasthatIgethimaglassoficedteaandtalktohimButagainIhadlaundrytodoandthehousetoclean. ThemorningonSundayJanuary161995myfathertelephonedmeasusualthistimehehadseemedtohaveforgottensomethingswehaddiscussedtheweekbefore.IhadtogettochurchandIcuttheconversationshort. Thecallcameat440am.ThatdaymyfatherwassenttohospitalinFlorida.IgotonaplaneimmediatelyandIvowed发誓thatwhenIarrivedIwouldmakeupforthelosttimeandhaveanicelongtalkwithhimandreallygettoknowhim. IarrivedinFloridaat100ambutmyfatherhadpassedawayat912pm.Thistimeitwashewhodidnothavetimetotalkortimetowaitforme. IntheyearssincehisdeathIhavelearntmuchaboutmyfatherandevenmoreabouteverysingleday. 1Weknowfromthereadingthatthefather. A.likedtopainthouses B.hadnofriendsaroundhim C.wasnothealthyinhisyouth D.thoughtofhisfamilyashisall 2Whenherfatherpaintedherfirsthousethedaughter. A.couldonlyaffordaglassoficedtea B.wastoobusytotalktoherfather C.coulddonothingbutholdapaintbrush D.spenteighthoursadayworkingwithherfather 3OnJanuary161995thedaughterfeltthatherfather. A.seemedtobealittledifferent B.hadnotimetophoneherasusual C.becameinterestedinchurch D.hadforgottentodiscusssomethingswithher 4Inthereadingtheunderlinedphrase‘gettoknowhim'mostprobablymeans. A.gethimtoknowher B.knowmoreabouthim C.gethimtoknowhimself D.makehimwell﹣known 5Whichisthebesttitleofthereading? A.PaintingHouses B.Daughter'sFamily C.FatherandI D.Father'sphonecalls
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Paynoattentiontothosewholaughatyou.Whatmostishowyouseeyourself. A.matters B.minds C.cares D.counts
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.
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Manypeoplethinkheroesneedtobehandsomerichorverysmart.Butasformeaheroisapersonwhoalwayshelpsothers. MyheroisUncleBill.Heistheeldestsonofaworkerandhegrewupinapoorfamilywithfouryoungerbrothersandtwolittlesisters.Hehadtogiveupschoolathisveryyoungage.Heworkedandgaveallhismoneytohisparents.Whenhewasgettingolderhefoundthathewasveryinterestedinfixingthings.Hecollectedbrokenthingswhichpeoplethrewawayandfixedthemintogoodones.Hecouldfixalmosteverythingthatdidnotwork.Heworkedhardandnevergaveup.Finallyheopenedhisownrepairshop.Ittookhimabout20yearstobecomeasuccessfulshopkeeper店主. Nowheisveryrichandhasfourothershops.Butheneverforgetsthedayswhenhehadnothing.Hegivesmoneytopoorfamilieshelpspoorkidsbuybooksandoffersthemfreelunches.Healsoencouragespeopletorecyclethings.HealwayssaysMakegooduseofwhatyouhavebecausewejusthaveoneearth.Hevolunteerstocleantheenvironmentinourneighborhood. 1WhatdoesUncleBill'sfatherdo? A.Heisashopkeeper. B.Heisaworker. C.Heisamathteacher. D.Heisafarmer. 2HowmanybrothersandsistersdoesUncleBillhave? A.7. B.6. C.5. D.4. 3WhydoesthewriterthinkUncleBillisahero? A.Heisrichandsmart. B.Heisasuccessfulshopkeeper. C.Healwaystrieshisbesttohelpothers. D.Heisgoodatfixingbrokenthings. 4WhichofthefollowingisTRUEaccordingtothepassage? A.UncleBillisnotgoodatfixingthings. B.UncleBillownsfiverepairshops. C.UncleBillforgetsthedayswhenhehadnothing. D.UncleBillcaresaboutnotpeoplebuttheenvironment. 5What'sthebesttitleforthispassage? A.UncleBill﹣MyHero B.ASuccessfulShopkeeper C.ProtectOurEarth. D.Let'sHelpEachOther.
解方程 χ﹣χ＝ 42＝χ．
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A.遵循 不变 不遵循 上升 遵循 下降 不遵循 不变
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