单项选择题专题复习

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专题01单项选择100题(考点全囊括)八年级英语上册期末复习查缺补漏冲刺满分(人教版)含答案

专题01单项选择100题（考点全囊括）期末真题+名校模拟一、单项选择1．Doing exercise is a good way for us to build ________ up.A．myself B．ourselves C．we D．yourself 2．Alice spent her spare time in going to the cinema ________ doing some sports. A．instead of B．in front of C．next to D．because of 3．We can learn a lot ________ history ________ the stamps.A．about；at B．of；at C．about；from D．of；in 4．You must do your homework_________.A．for yourself B．by you C．by yourself D．to yourself 5．—You don’t look happy. What’s wrong?—I’m well. There is _______.A．something serious B．serious somethingC．nothing serious D．serious nothing6．—Zhao Liying is a famous actor.—Yeah, she is popular _______ many young people.A．for B．as C．with D．to 7．Zhou Jielun is famous ________ his music.A．as B．for C．with D．of8．I borrowed a lot of story books ________ Li Ming.A．of B．to C．for D．from 9．I’m afraid ________ meeting him.A．of B．to C．in D．at 10．—May I ask you _______ questions?—Sure. Go on.A．some B．any C．much D．few 11．We should sleep ________ eight hours a day, or it’s bad for our health.A．at most B．most C．least D．at least12．Bob likes playing football. Because it makes him ________.A．healthy B．health C．ill D．weak13．—What do you do ________?—I practice ________ exercise.A．everyday; everyday B．everyday; every dayC．every day; everyday D．every day; every day14．My brother learns English by ________ English videos. He thinks it is fun and useful.A．watch B．watching C．watched D．to watch15．The number of the trees around my village is getting ________.A．larger and larger B．higher and higher C．more and more D．less and less16．I want to invent a mobile phone that can be used in the rain. ________, I don’t know how to do that. A．So B．But C．However D．Because17．Roger spent ________ time but did ________ work than Betty.A．little; much B．less; more C．little; more D．less; much18．The _________ exercise you do before running, _________ you’ll get hurt while running. A．less; more easily B．less; the more easilyC．fewer; more easily D．fewer; the more easily 19．__________ it is raining, I think it is a good idea to stay at home.A．When B．Since C．If D．Although20．The time will not be __________ enough for my homework.A．near B．almost C．hardly D．nearly21．—Harry gave a good speech yesterday.—Yes, he did. ________, it was his first time to give a speech in public.A．In fact B．In short C．On the other hand D．Even though22．Gu Ailing is a great player. She ________ great interest in sports when she was very young. A．shared B．hated C．showed D．played23．Wendy was very ________ because she fought with her best friend yesterday.A．serious B．terrible C．unhappy D．active24．Many wild animals are ________, because people kill them for their fur and meat.A．on earth B．at last C．in danger D．in fact25．Tom’s children are going to ________ him to Rome next week.A．get B．follow C．arrive D．reach 26．Maria can swim ________ a fish.A．as well as B．as good as C．as long as D．as quick as 27．Don’t laugh. This is a ________ question: Do you really like your job?A．funny B．popular C．friendly D．serious 28．Soon Wolfgang played ________ his big sister, Nannerl.A．as better as B．as well as C．as good as D．as best as 29．—_______ kind of music do you like best?—Classical music.A．How B．Which C．What D．How many 30．Our school team _________ the football match yesterday.A．wins B．won C．beats D．beat 31．Friends are helpful to us and we should learn to ________ our happiness with them. A．share B．lend C．show D．give 32．—What do you think of Wu Song in the movie?—He is very ________ because he killed a tiger by himself.A．poor B．serious C．stupid D．brave 33．—Doctor, what should we do to ____________ the flu?—Do some exercise every day.A．choose B．prevent C．stretch D．force 34．My little brother has so many hobbies,________ singing and running.A．for example B．such as C．as if D．for35．I left my tape（磁带）at home. Can you _______ me yours?A．lend B．borrow C．keep D．give 36．Let’s play a game. Please keep our eyes ________.A．close B．closing C．to close D．closed 37．She likes lots of animals ________ dogs, cats and rabbits。

济南版2019-2020学年七年级上册生物专题复习：单项选择题100道

济南版2019-2020学年七年级上册生物专题复习：单项选择题100道姓名:________ 班级:________ 成绩:________一、单选题1 . 铁线蕨长得比苔藓植物高大的原因是：（）A．有了茎和叶的分化B．根、茎、叶中有机械组织和输导组织C．叶柄较长D．具有了真正的根、茎、叶等器官2 . 下列关于细菌的叙述中，正确的是A．细菌的生殖方式是孢子生殖B．细菌没有成形的细胞核C．细菌都对人体都有害D．细菌既有单细胞的，也有多细胞的3 . 下列选项中，属于生物的是（）A．树的枯叶B．电脑病毒C．兰花螳螂D．机器人4 . 吃梨时甘甜可口的梨汁，主要来自梨细胞的（）A．液泡B．细胞核C．细胞膜D．细胞质5 . 下面是对“绿叶在光下制造有机物”实验的相关描述，其中不正确的是（）A．该实验的原理：淀粉遇碘变蓝色B．该实验的步骤：遮光→照光→脱色→漂洗→染色→漂洗→观察C．该实验的现象：遮光部分不变蓝，照光部分变蓝色D．该实验的结论：光是光合作用的必要条件，淀粉是光合作用的产物6 . 每个多细胞生物体都不是细胞随意堆砌形成的，而是有组织、器官等结构层次的。

以下的叙述中正确的是（）A．能接受刺激产生兴奋并传导兴奋的组织是结缔组织B．动物体的结构层次是：细胞→组织→器官→动物体C．一粒水稻种子属于一个器官D．贯穿于植物体的根、茎叶等器官内的组织是分生组织7 . 日常生活中，我们主要食用根部的一组蔬菜是（）A．山药、土豆、洋葱B．洋芋、大蒜、甘蓝C．甘薯、萝卜、胡萝卜D．荸荠、塘藕、花椰菜8 . 下列不属于生物适应环境的是（）A．在荒漠中生活的骆驼的尿液非常少B．仙人掌的叶变成了刺C．鲫鱼在淡水中生活D．蚯蚓疏松土壤9 . 下面表中的生物之间是吃与被吃的关系，数字是它们体内某种有毒物质的含量，能真实反应它们之间吃与被吃的关系的食物链是（）生物A B C D E有毒物质90305002007A．A→B→C→D→E B．E→B→A→D→C C．C→D→A→B→E D．E→D→C→B→A10 . 1864年德国科学家萨克斯将绿色叶片放在暗处12h，再将此叶片的一部分用锡箔遮光后，进行曝光．光照一段时间后，用碘蒸汽处理叶片，结果发现叶片的曝光部分显蓝色，遮光部分显棕色，如图所示．该实验可以证明的是（）A．光合作用既需要阳光又需要水B．光合作用需要水并能产生淀粉C．光合作用不需要水也能产生淀粉D．光合作用需要阳光并能产生淀粉11 . 深秋季节位于路灯旁的树叶比同株树上而远离路灯的叶子A．先黄B．晚一点黄C．一起黄D．永不黄12 . 下列有关生物实验的叙述，错误的是（）A．制作洋葱鳞片叶内表皮细胞临时装片时，载玻片中央滴的是清水B．制作临时装片盖盖玻片时，让盖玻片的一边先接触液滴，然后缓缓放下C．绿叶在光下制造有机物的实验中，把叶片直接放在清水中加热脱色D．观察小鱼尾鰭内血液的流动实验中，管径最小的血管内红细胞单行通过13 . 白毛巾被绿色的菠菜弄脏，欲去除毛巾上的绿渍，宜选用（）A．普通洗衣粉B．酒精C．沸水D．肥皂水14 . 下列农业生产采取的措施中，有利于植物进行呼吸作用的是（）A．庄稼被淹后及时排涝B．刚移栽的植物遮阴处理C．适当降低夜间大棚内的温度D．收获的粮食入仓前晒干15 . 下列关于草履虫的说法中，正确的是A．草履虫体内有叶绿体B．草履虫的呼吸和排泄都是靠表膜完成的C．实验时，应从培养液的底层吸取草履虫D．在载玻片的液满上放几丝棉花纤维的目的是限制草履虫的运动16 . 对生物的生存来说，不是它生长的基本条件的是A．一定的生存空间B．适宜的温度C．营养物质D．时间17 . 在“绿叶在光下制造淀粉”的实验中，实验后向叶片滴加碘液，未变蓝的部位是A．光照部位B．遮光部位C．整个叶片D．叶片边缘18 . 光合作用的实质是（）A．制造有机物、释放能量 B. 分解有机物、储存能量B．制造有机物、储存能量 D. 分解有机物、释放能量19 . 如图表示“绿叶在光下制造淀粉”实验的相关描述中，下列说法正确的是（）A．滴加碘液和显色后，叶片上用黑纸片遮光的部分呈蓝色。

中考数学专题复习题：整式及其加减

中考数学专题复习题：整式及其加减一、单项选择题（共10小题）1．单项式32xy -的系数是（）A ．3B ．4C ．2-D ．22．下列代数式的书写符合规范的是（）A ．112a B ．a 2÷5C ．ab 6D ．3b 3．多项式222a b ab a --的项数及次数分别是（）A ．3，3B ．3，2C ．2，3D ．2，24．关于字母x y ，的多项式22338x kxy y xy --+-化简后不含xy 项，则k 为（）A ．0B ．13-C ．13D ．35．若25a 4b n 与-27a m b 3是同类项，则m 、n 的取值为（）A ．m =2，n =3B ．m =4，n =2C ．m =3，n =3D ．m =4，n =36．下面的说法中，正确的是（）A ．x +3是多项式B ．(-2)3中底数是2C ．335ab 的系数是3D ．单项式-ab 2的次数是2次7．下列代数式中，符合书写规则的是（）A ．112xB ．x ÷yC ．m ×2D ．3mn 8．小明在计算一个二项式的平方时，得到的正确结果是4x 2+12xy +■，但最后一项不慎被污染了，这一项应是（）A ．3y 2B ．6y 2C ．9y 2D ．±9y 29．已知一个多项式与322853x x x -+-的和等于3221452x x x -+-，则这个多项式一定是（）A ．32461x x ++B ．261x +C ．261x -+D ．265x --10．在多项式()a b c d --+-(其中a b c d >>>)中，对每个字母及其左边的符号（不包括括号外的符号）称为一个数，即：a -为“数1”，b 为“数2”，c +为“数3”，d-为“数4”，若将任意两个数交换位置，后得到一个新多项式，再写出新多项式的绝对值，这样的操作称为对多项式()a b c d --+-的“绝对换位变换”，例如：对上述多项式的“数3”和“数4”进行“绝对换位变换”，得到−−−+，将其化简后结果为a b c d +--，…下列说法：①对多项式的“数1”和“数2”进行“绝对换位变换”后的运算结果一定等于对“数3”和“数4”进行“绝对换位变换”后的运算结果；②不存在“绝对换位变换”，使其运算结果与原多项式相等；③所有的“绝对换位变换”共有5种不同运算结果．其中正确的个数是（）A ．0B ．1C ．2D ．3二、填空题（共5小题）11．多项式322283a ab ac -+-是________次________项式，它的常数项是________．12．23m x y -与35n x y 是同类项，则m n +=________。

小升初英语专题复习单项选择题专项练(通用,含答案)

单项选择题专项练1．Thank you _______ your help. ()A．to B．for C．in 2．—What happened __________ you? ()—I fell down and hurt my leg.A．to B．in C．at3．—Did you go to the zoo __________ bike? ()—Yes, I did.A．with B．by C．to4．—Did you __________ fresh food in your grandparents’ home last week? () —No, I didn’t.A．eat B．ate C．eats5．He is going _________ on a trip to Xi’an. ()A．going B．to go C．go6．It was a bad day _______ also a good day. ()A．but B．or C．and 7．There _______ any computers in 1945. ()A．are not B．were no C．were not 8．John got a nice gift yesterday. He looked __________. ()A．sad B．happy C．tired9．I was short before, so I __________ ride my bike well. ()A．can B．couldn’t C．could 10．This is __________ good news __________ you. ()A．a; to B．a; for C．/; for 11．There __________ a farewell party tomorrow evening. ()A．are B．was C．will be 12．Will you help me __________ my lost key? ()A．look for B．find out C．looking for 13．__________ did you go to Tianjin? ()A．What B．Where C．How14．I __________ a new bike yesterday afternoon. ()A．buy B．buys C．bought 15．I saw an animal. It __________ a little dog. ()A．looked like B．looks like C．look like 16．He jumped into the lake and __________ to it. ()A．swim B．swimming C．swam 17．—How __________ your holiday? ()—Great.A．was B．are C．were 18．I’m 46 kilograms and my sister is 43 kilograms. I am ________ than her. () A．taller B．shorter C．heavier 19．—How __________ are you? ()—I am 13 years old.A．tall B．old C．heavy 20．My brother is shorter __________ me. ()A．then B．than C．and 21．—What _______ he _______ this morning? ()—He played the violin.A．did; did B．does; do C．did; do 22．Did you __________ any gifts to your mother? ()A．give B．gives C．gave 23．How __________ your vacation? ()A．is B．was C．did 24．—How ________ are you? ()—I’m 1.64 metres.A．tall B．heavy C．long 25．This dinosaur is taller than both ____________ us together. ()A．and B．of C．for 26．My hands are bigger than _____. ()A．your B．yours C．him 27．I’m 48 kilograms. I'm ________ than you. ()A．heavier B．younger28．He is going to buy a storybook _____. ()A．last week B．tomorrow C．yesterday29．I am _____ music now. ()A．listen to B．listening C．listening to 30．My parents _____ to work by car, and my uncle _____ to work by bus. () A．go; goes B．goes; goes C．goes; go 31．Spring is coming! The sky is _____ and the sun is _____. ()A．bright; clear B．clearer; brighter C．clearest; brightest 32．I watched some _____ shows _____ TV. ()A．children; In B．children's; In C．children's; on 33．Peter _____ sick yesterday. ()A．feels B．feel C．felt34．—My father is ill. ()—___________A．He should take a deep breath.B．He should see a doctor.C．He should count to ten.35．If you see the yellow light, you must _______. ()A．slow down and stop B．drive quickly C．run fast 36．This sign means “_______”. ( )A．Keep to the right B．Talk quietly C．Take turns 37．—It's cold outside. ()—__________A．Take off your hat. B．Put away your scarf. C．Put on your gloves. 38．My aunt is a _______. She works at a university. ()A．scientist B．police officer C．pilot39．My mother is going to make mooncakes on _______. ()A．New Year's Day B．Mid-Autumn Day C．Children's Day 40．We need to ____________ water every day. ()41．On the bus, we ____________ give the seat to old people. () A．should B．sho uldn’t C．can’t 42．Kitty comes to school _____________ bike. ()A．by B．on C．in 43．Let’s go .()A．swiming B．swimming C．swim 44．There ________ some children in the classroom. ()A．is B．am C．are 45．—Can you come with me? ()—Yes, I ____________.A．can B．can’t C．could 46．She _____________ very short. ()A．is B．am C．are 47．—____________ are they doing? ()—They are watching TV.A．When B．What C．Which 48．—_____________ you in the kitchen, Tom? ()—Yes, I am.A．Is B．Am C．Are参考答案1．B【详解】句意：感谢你的帮助。

专题单项选择100题(重点知识)-2022-2023九年级英语上学期期末复习查缺补漏冲刺满分人教版

专题单项选择100题（重点知识）-2022-2023学年九年级英语上学期期末复习查缺补漏冲刺满分人教版人教版九年级英语上学期期末复习查缺补漏冲刺满分(重点知识)专题01 单项选择100题1．─I'm sorry，Mr .Li. I have __________ my English homework at home.─Don't forget __________ it to school tomorrow.A．left；to bring B．forgotten；to take C．left；bringing D．forgotten；taking2．My daughter got up and dressed herself quickly when her alarm clock __________. A．ran off B．went off C．set off D．shut off3．__________ people visit the museum every year.A．Thousands B．Thousand of C．Thousands of D．Ten thousands 4．Twenty minutes later，the rainbow __________ in the sky. I couldn't see it any more. A．appeared B．disappeared C．covered D．discovered5．Eddie was sleeping _______ Millie was reading a magazine.A．until B．while C．before D．after6．Yesterday was our School Day. All the students in my class __________.A．made up B．stayed up C．woke up D．showed up7．─When did you __________，Jack？─I've _____for two years.A．be married；got married B．get married；been marriedC．married；got married D．been married；got married8．─All the oil in the world will __________ some day.─Yeah. What shall we use for power at that time？A．give away B．put away C．run out D．set out9．. The plane ______ when we got to the airport.A．had taken off B．was taken off C．will take off D．is taking off10．I saw the man put __________ apples in the basket and go out.A．the all B．whole the C．all the D．a whole11．─You're always studying hard！─Because I want to get good grades and I don't want to __________ my parents. A．drive B．disappoint C．examine D．pull12．Neither Jack nor his deskmate __________ from Canada. Both of them__________from Australia.A．is；is B．is；are C．are；are D．are；is13．If you __________，you'll finish the work soon.A．give up B．talk back C．go ahead D．pull together14．（易错题）We all knew that Li Yan was close __________ the match.A．win B．to win C．won D．to winning15．Many students said that they were willing to work hard to make their dreams__________ true. And this always makes them __________.A．come；happy B．to come；happy C．come；happily D．to come；happily16．─I'm worried about my grades in the final exams.─The result is important，but don't be __________ yourself.A．patient with B．hard on C．proud of D．sure about17．Welcome to our school ,ladies and gentlemen. _______, I’d like to introduce myself. A．To be honest B．To my surpriseC．To start with D．To tell you the truth.18．─Walking more is good for our health.─So I would rather __________ an hour's walk to work instead of __________ a car. A．take；drive B．take；to drive C．to take；driving D．take；driving 19．─Would you like to go with me to the party？─Wait a moment. I'll go with you __________ I buy some snac ks.A．as well as B．so that C．as soon as D．only then20．It __________ him three days to find a happy man for the king.A．spent B．paid C．cost D．took21．What should I do when I meet a person _______ the first time?A．in B．at C．on D．for22．We often _______ our friends’ homes without _______ them first.A．drop by; call B．drop by; calling C．visit; call D．visits; calling 23．She looks_____ because she has a ________vacation.A．relaxed , relaxed B．relaxing ,relaxingC．relaxed, relaxing D．relaxing ,relaxed,24．（易错题）Everyone except Mary and Lily _______ there when the meeting began. A．is B．was C．are D．were25．I think you should help him. _______ he is your good friend.A．Above all B．After all C．At all D．In all26．His friend got the good job after the manager saw how he _______ when he was waiting for the interview.A．imagined B．realized C．succeeded D．behaved27．—It's getting cold. Would you mind _______ the windows?—Of course not.A．closing B．to close C．closed D．to closing28．I cut the orange _______ and ate it _______ a fork.A．down；use B．up；use C．down；with D．up；with29．Be polite to the old，my dear! You _______ have good manners.A．prefer to B．are supposed to C．are used to D．are good at30．— What are people supposed to do when they meet for the first time in the US?— ________A．They’re supposed to kiss each other. B．They’re supposed to bow.C．They’re expected to shake hands. D．They’re expected to hug.31．—What kind of music do you like?—I like music that I can sing along _______ or dance _______.A．to；with B．with；to C．to；to D．/；/32．—Do you prefer basketball with me?一No,I’d rather at home and watch TV.A．play;stay B．to play;to stayC．play;to stay D．to play;stay33．—What are you looking for?—I’m looking for the dictionary you lent me last week.A．who B．what C．that D．when34．I love the book that _______ by my brother last week.A．bought B．was bought C．were bought D．was buying35．The successful man has made _______ money，and he has helped many students with it.A．a great many B．quite a few C．the number of D．plenty of36．The artist received high from the art community for these sculptures. A．praise B．prize C．price D．pride37．—I'm afraid I can't perform well tomorrow.—_______ ! I'm sure you'll make it.A．That's a problem B．That's right C．Cheer up D．It's a pity38．（易错题）The organization can _______ the poor _______ food and drinks. A．offer；with B．offer；to C．provide；for D．provide；with39．_______ your dream，and go for it. I believe you can succeed in the end.A．Hear from B．Take after C．Stick to D．Depend on40．--Let's go for a picnic on Saturday, James.-- _____. I have to do my homework at homeA．What a pity B．Don't worry. C．Best wishes D．How come? 41．They saw something strange in the sky. They thought it must be ____________ alien. A．a B．/ C．the D．an42．-Do you know who the pen ____________？-Sorry，I don't know.A．belong B．belong to C．belongs D．belongs to43．-Listen，who's knocking at the door？Can it be Jim？-No，it can't be him. It must be ____________ .A．anyone else B．someone else C．else anyone D．else someone44．I have no fun ____________ too much homework every day.A．do B．doing C．done D．did45．I looked through my test paper again and again ____________ I wouldn't make any mistakes.A．so B．because C．so that D．when46．He is ______fat because he eats ______ meat.A．much too, much too B．too much, too muchC．too much, much too D．much too, too much47．_____Roy ____Jean speaks good English, so they can communicate with these American students very well.A．Neither; nor B．Not only; but alsoC．Both ;and D．Either; or48．The bag must be ____________.A．Li Lei's and Li Ping' s B．Li Lei and Li Ping’s C．Li Lei's and LiPing D．Li Lei and Li Ping49．I saw Tom ____________ basketball with his friends when I passed the playground. A．to play B．plays C．play D．playing50．At the end of each day, you should make a list of ____________ next day.A．what will you do B．what you will do C．what did you do D．what you did51．The New Silk Road will offer a good _________ for more nations to communicate. A．chance B．change C．question D．habit52．Mrs. Brown is a teacher of _________, and her daughter is _________ girl.A．40 years old; a 8-year-old B．40-years-old; a 8 years oldC．40 years old; an 8-year-old D．40-year-old; an 8 years old53．The boy doesn’t do his homework _________, though he has _________. A．careful enough; enough time B．enough careful; time enoughC．carefully enough; enough time D．enough carefully; time enough54．Emma is such a good girl that she never _________ her parents.A．takes care of B．talks back to C．worries about D．listens to55． Sorry, your car ______ in front of the hotel.A．can put B．be not putC．can’t be put D．can be not put56．There is something wrong with his computer. He plans to get it ________ this afternoon.A．repairing B．repaired C．to repair D．repairs57．This kind of medicine _________ in a dry and cool place.A．keep B．must keep C．must be kept D．must be keeping58．If you want to stay healthy, you should _________ junk food.A．keep away from B．look forward to C．get along with D．come up with 59．At present all Chinese couples _________ to have two children.A．is allowed B．allowed C．are allowed D．were allowed 60．—Excuse me. It’s not allowed to take photos here.— _________ .A．Thank you very much B．Here you are C．That’s too bad D．It doesn’t matter61．The trousers with wide legs are in the newest _________. Many girls wear them. A．brand B．trade C．style D．product62．Mr. Lu divided us _________ four groups to practice the conversation.A．among B．into C．from D．by63．—Excuse me, sir, but is this umbrella yours?—Oh, sorry. I just took it _________. Mine is behind the door.A．by chance B．in chance C．in mistake D．by mistake64．Beth said nothing could stop her ____ her dream.A．to achieve B．from achieving C．in achieving D．for achieving 65．—Can you kick the ball to _________ end of the football field?—It’s hard for me. I think few goalkeepers can make it.A．another B．the other C．other D．the another66．Jim to hospital at once after he got hurt．A．sent B．is sentC．will be sent D．was sent67．﹣Where will the 2022 Winter Olympics____，Cindy？﹣In Beijing， the capital of China，the first city to host both Summer and Winter Olympics．A．be taken place B．take placeC．take part D．be taken part68．If we continue to kill elephants for the ivory, we humans will lose them _________. A．in the end B．at the end C．in end D．at end69．- I had a good time in the study trip last week.- ________A．With pleasure. B．Thank you. C．OK! D．I'm glad to hear that. 70．— Alice, can you help me with my English homework?—_________. I’m good at English.A．Good luck B．You’re welcome C．With pleasure D．Never mind 71．__________ when I was in trouble, my best friends always help me.A．Pay attention to B．No matterC．According to D．Thanks to72．— Your sweater looks nice. Is it made __________cotton?— Yes, and it was made __________ Shanghai.A．of; by B．of; in C．from; by D．from; in73．You must be more careful and ______ the same mistake you’ve ever made. A．plan B．follow C．avoid D．enjoy74．It takes him twenty minutes __________ to school.A．to walk B．walking C．walks D．walk75．Both Mike and I ____ ready for the new high school life.A．be B．am C．is D．are76．My mother seemed __________ tired, so I asked her to stop to have a good rest. A．to get B．getting C．got D．to getting77．Most young people find ________ exciting to watch a football match.A．this B．that C．it D．one78．Mr. Wang decided to buy that bike __________ it was very expensive.A．even though B．so that C．because D．as if79．A year has four seasons and it________ twelve months.A．divide into B．is dividing intoC．divided into D．is divided into80．The soldiers were so tired that they could __________ keep their eyes open after a long journey.A．quickly B．hardly C．easily D．widely81．-----What are you going to do next month?-----I am going to travel to Germany, which is ______ European country.A．a B．an C．the82．I saw Li Ming ______ near the river on my way home.A．plays B．playing C．to play D．played83．— How does Tom go to the office?— He __________ drive a car, but now he __________ there to keep healthy. A．used to; is used to walk B．was used to; is used to walkingC．was used to; is used to walk D．used to; is used to walking84．My brother is a __________ young man. He often tells jokes to make us laugh. A．strict B．proud C．rude D．humorous85．She doesn’t feel _____ though she is ____.A．alone , lonely B．lonely , lonely C．lonely, alone D．alone , alone 86．Mrs. Smith wouldn’t leave the TV se t, __________ her children were waiting for their supper.A．if B．because C．even though D．as soon as87．The boy is such an excellent table tennis player in our school that we __________ him.A．are proud of B．are afraid of C．takes pride in D．takes care of 88．It’s said that the number of forest parks in Guang-dong __________ to more than 1,000 so far.A．increase B．have increased C．has increased D．increases89．--Wechat (微信) really influences people's life.-- _________ . It is easier for us to keep in touch with others.A．Mainly B．Exactly C．Simply D．Mostly90．— Mr. Chen said he __________ teaching English because he loved children.— Yes, and his love for children and teaching made him a great teacher.A．turned up B．gave up C．took up D．set up91．—Do you know where the post office is? I want to buy______.—Of course. Follow me, please.A．textbooks B．stampsC．shoes D．lanterns92．— Would you like to go swimming in the river, John?—Swim? Sorry, our teachers always tell us _________ in the river without parents’ company.A．don’t swim B．to not swim C．not swimming D．not to swim93．I spend fifteen minutes _________ to school every day.A．to walk B．walk C．walking D．walked94．This morning my mother asked me __________.A．why he is not hereB．where Julia went last weekendC．what time is itD．how did my brother do it95．— Could you please open the door for me, Jim?—_________? I didn’t hear clearly.A．Sure B．What C．Pardon D．Really96．I _________ a movie theater on the way to school.A．pass on B．pass by C．pass through D．pass away97．WeChat（微信）makes it more _________ for people to communicate with each other.A．convenient B．important C．necessary D．impossible98．Look at the picture on the right! She is going ________.A．into the library B．out of the post officeC．into the supermarket D．out of the bank99．Jack is so little a boy, but he always talks to others _________.A．polite B．politely C．impolite D．impolitely100．—What about this computer game? It’s _________.—But it’s _________interesting. Let’s buy that one though it’s not cheap. A．expensive; less B．expensive; moreC．inexpensive; less D．inexpensive; more参考答案：1．A【详解】句意：——对不起，李老师。

高考数学专题复习题：单调性与最值

高考数学专题复习题：单调性与最值一、单项选择题（共9小题）1.下列命题中正确的是（）A.y=cos x在第一象限和第四象限内单调递减B.y=sin x在第一象限和第三象限内单调递增C.y=cos x在[−π2,π2]上单调递减D.y=sin x在[−π2,π2]上单调递增2.y=2sin(3x+π3)的值域是（）A.[-2,2]B.[0,2]C.[-2,0]D.[-1,1]3.“0<x<π6”是“sin x<12”的（）A.充分不必要条件B.必要不充分条件C.充要条件D.既不充分也不必要条件4.已知函数y=sin x与y=cos x，在下列区间内同为单调递增的是（）A.(0,π2)B.(π2,π)C.(π,3π2)D.(3π2,2π)5.已知函数f(x)=sin(x+π6)在x0处取得最大值，则x0可能是（）A.π6B.π4C.π3D.π26.使cos x=1-m有解的m的取值范围为（）A.m≥0B.0≤m≤2C.-1<m<1D.m<-1或m>17.如果f(x)=sinωx(ω>0)在区间[0,π3]上单调递增，在区间[π3,π2]上单调递减，那么ω的值为（）A.2B.23C.43D.328.在△ABC中，角A、B均为锐角，且cos A>sin B，则（）A.cos C>0B.cos C<0C.cos C=0D.cos C≥09.对于函数f(x)={sinx,sinx≥cosx,cosx,sinx<cosx,下列说法中正确的是（）A.该函数的值域是[-1,1]B.当且仅当x=2kπ+π2(k∈Z)时,函数取得最大值1C.当且仅当x=2kπ-π2(k∈Z)时,函数取得最小值-1D.当且仅当2kπ+π<x<2kπ+3π2(k∈Z)时,f(x)<0二、填空题（共3小题）10.函数y=cos x在区间[-π,a]上单调递增，则a的取值范围是________.11.若a=sin1，b=ln(sin1)，c=e sin1，则a、b、c三个数中最小的数为________.12.函数y=sin(ωx+π3)(ω>0)在区间(−π6,π3)上单调递增，则ω的取值范围是________.三、解答题（共3小题）13.已知函数f(x)=2cos(3x+π4).（1）求f(x)的单调递增区间;(5分)（2）求f(x)的最小值及取得最小值时相应的x值.14.设函数f(x)=√2sin(2x−π4),x∈R.（1）求函数f(x)的最小正周期和单调递增区间.（2）求函数f(x)在区间[π8,3π4]上的最小值和最大值,并求出取最值时x的值.15.定义在R上的函数f(x)满足f(x+1)=-f(x)，且在[-4,-3]上单调递增，若α,β是锐角三角形的两个内角，求证：f(sinα)>f(cosβ).。

高考生物专题复习题：生态系统

高考生物专题复习题：生态系统一、单项选择题（共6小题）1.人工生态系统是指经过人类干预和改造后形成的生态系统。

建立人工生态系统旨在模拟自然生态系统的组成和功能，促进人类活动、自然生态和社会经济条件的良性循环。

下列有关叙述正确的是（）A．草原生态系统和农田生态系统均属于人工生态系统B．人工生态系统中物质和能量的循环利用可以减少资源浪费C．人工生态系统只通过生物之间的共同进化即可实现生态平衡D．增大人工生态系统食物网的复杂程度有利于提高人工生态系统的稳定性2.健康稳定的生态系统可为人类提供可持续的服务，且具有较好的自我调节能力，受到外界干扰时能够较快地恢复到平衡状态。

下列关于生态平衡和生态系统稳定性的叙述，错误的是（）A．生态平衡具有结构、功能和收支平衡三个特征B．合理适度地利用生态系统有助于维持生态平衡C．物种间信息传递有利于生态系统的平衡与稳定D．生态系统的组分越少，其恢复力稳定性就越强3.珊瑚生态系统主要由珊瑚礁及生物群落组成，生物多样性丰富。

有关叙述正确的是（）A．珊瑚虫为寄生于体内的虫黄藻提供含氮物质，后者也为前者提供有机物质，两者关系有利于群落资源充分利用B．珊瑚生态系统具有抵抗不良环境并保持原状的能力，这是恢复力稳定性的表现C．珊瑚生态系统中某种生物不同个体长相各异体现物种多样性D．珊瑚生态系统生物多样性的形成是协同进化的结果4.关于生态系统的叙述、正确的是（）A．生态系统的碳循环是指CO2不断进行着从非生物环境到生物群落，又从生物群落到非生物环境的循环过程B．如果一个生态系统在一段较长时间内没有来自系统外的太阳能或化学能的输入，这个生态系统就会崩溃C．利用性外激素扰乱某些有害昆虫的雌雄交配，使其繁殖力下降，属于利用化学信息进行化学防治的过程D．生物富集是指生物体从周围环境吸收、积蓄某种元素或难以降解的化合物，使其在机体内浓度达到环境浓度的现象5.下列有关生态系统信息传递的叙述错误的是（）A．完整的信息传递过程包括信息源、信道和信息受体B．利用光照、声音信号诱捕或驱赶某些动物，使其远离农田，属于生物防治C．生态系统信息通过食物链（网）传递，具有循环的特点D．信息传递可以维持种群繁衍、调节种间关系，维持生态平衡6.下列有关生态系统的结构，叙述不正确的是（）A．生态系统结构包括非生物物质和能量、生产者、消费者、分解者、食物链和食物网B．生产者就是自养生物，多数能进行光合作用，是生态系统的主要成分C．分解者就是细菌和真菌，能将动植物遗体中的有机物分解成无机物D．细菌既可以作为生产者，也可以作为消费者和分解者二、多项选择题（共4小题）1.某池塘生态系统的能量流动如下图所示，图中的英文字母表示能量（单位：KJ）。

高考生物专题复习题：体液调节

高考生物专题复习题：体液调节一、单项选择题（共6小题）1.正常机体在寒冷环境和炎热环境中都可以通过调节保持体温恒定。

下列有关两种环境下体温调节的叙述错误的是（）A．两种环境下人体下丘脑体温调节中枢都处于兴奋状态B．两种环境下机体通过实现产热和散热的平衡维持体温正常C．两种环境下都可促进甲状腺激素、肾上腺素等激素的释放D．两种环境下都可通过自主神经系统调节血管及汗腺的分泌2.胰岛素抵抗是指胰岛素促进葡萄糖摄取和利用的效率下降的现象。

以往研究显示，未知应激因素引起的胰岛素抵抗可导致补偿性高胰岛素血症。

某团队新发现，APT1酶功能的丧失亦可导致高胰岛素血症，具体机理如图所示。

下列说法错误的是（）A．胰岛素受体功能缺失或表达量下降可能导致胰岛素抵抗B．胰岛素抵抗引起高胰岛素血症时，机体血糖含量可能正常C．APT1酶也通过引起胰岛素抵抗进而诱发高胰岛素血症D．APT1酶可通过影响Scamp1的功能减少胰岛素的释放量3.侏儒症患者生长迟缓，身材矮小，病因是患者幼年时生长激素分泌不足。

呆小症患者不但身材矮小，而且智力低下，病因是患者幼年时甲状腺激素分泌不足。

下列关于两类疾病及两种激素的说法，正确的是（）A．两类疾病患者都可在幼年时口服相应的激素来缓解症状B．呆小症患者可以说明激素能影响神经系统的发育C．两种激素的分泌都存在分级调节和反馈调节机制D．两种激素分泌后都只能运输到相应的靶细胞4.人体抗利尿激素的水平取决于血浆渗透压，而醛固酮的水平与血钠含量有关，同时两种激素的分泌也受到循环血量的调控，当血量减少时，两种激素的分泌量都增加。

下图为一次饮1000mL清水和1000mL生理盐水的甲、乙个体内排尿率随时间变化曲线。

下列关于甲乙个体的生理变化说法正确的是（）A．甲个体内由垂体释放的抗利尿激素减少而乙恒定不变B．乙个体肾小管集合管受体与醛固酮结合而甲不需要C．甲乙个体都需通过调节尿量及尿的成分实现水盐平衡D．甲乙个体的血浆渗透压在a操作后半小时内保持不变5.正常成年人空腹血糖3.9~6.1mmol/L，餐后2小时血糖<7.8mmol/L时为正常血糖浓度。

高考数学专题复习题：数学归纳法

高考数学专题复习题：数学归纳法一、单项选择题（共6小题）1．利用数学归纳法证明不等式1111()2321nf n ++++<- （2n ≥，且*n ∈N ）的过程，由n k =到1n k =+时，左边增加了（）A ．12k -项B ．2k 项C ．1k -项D ．k 项2．用数学归纳法证明：()()()1221121n n n ++++=++ ，在验证1n =成立时，左边所得的代数式是（）A ．1B ．13+C ．123++D ．1234+++3．用数学归纳法证明等式()()()3412332n n n +++++++= ()N,1n n ∈≥时，第一步验证1n =时，左边应取的项是（）A ．1B ．12+C ．123++D ．1234+++4．用数学归纳法证明：11112321n n ++++<- ，()N,1n n ∈≥时，在第二步证明从n k =到1n k =+成立时，左边增加的项数是（）A ．2k B ．21k -C ．12k -D ．21k +5．已知n 为正偶数，用数学归纳法证明1111111122341242n n n n ⎛⎫-+-+⋅⋅⋅+=++⋅⋅⋅+ ⎪-++⎝⎭时，若已假设n k =（2k ≥，k 为偶数）时命题为真，则还需要再证（）A ．1n k =+时等式成立B ．2n k =+时等式成立C ．22n k =+时等式成立D ．()22n k =+时等式成立6．现有命题()()()11*1112345611442n n n n n ++⎛⎫-+-+-++-=+-+∈ ⎪⎝⎭N ，用数学归纳法探究此命题的真假情况，下列说法正确的是（）A ．不能用数学归纳法判断此命题的真假B ．此命题一定为真命题C ．此命题加上条件9n >后才是真命题，否则为假命题D ．存在一个无限大的常数m ，当n m >时，此命题为假命题二、多项选择题（共2小题）7．用数学归纳法证明不等式11111312324++++>++++ n n n n n 的过程中，下列说法正确的是（）A ．使不等式成立的第一个自然数01n =B ．使不等式成立的第一个自然数02n =C ．n k =推导1n k =+时，不等式的左边增加的式子是()()12122k k ++D ．n k =推导1n k =+时，不等式的左边增加的式子是()()12223k k ++8．用数学归纳法证明不等式11111312324++++>++++ n n n n n 的过程中，下列说法正确的是（）A ．使不等式成立的第一个自然数01n =B ．使不等式成立的第一个自然数02n =C ．n k =推导1n k =+时，不等式的左边增加的式子是()()12122k k ++D ．n k =推导1n k =+时，不等式的左边增加的式子是()()12223k k ++三、填空题（共2小题）9．在运用数学归纳法证明()121*(1)(2)n n x x n +-+++∈N 能被233x x ++整除时，则当1n k =+时，除了n k =时必须有归纳假设的代数式121(1)(2)k k x x +-+++相关的表达式外，还必须有与之相加的代数式为________．10．用数学归纳法证明：()()122342n n n -+++++= （n 为正整数，且2n ）时，第一步取n =________验证．四、解答题（共2小题）11．用数学归纳法证明：()*11111231n n n n +++>∈+++N ．12．数学归纳法是一种数学证明方法，通常被用于证明某个给定命题在整个（或者局部）自然数范围内成立．证明分为下面两个步骤：①证明当0n n =（0n ∈N ）时命题成立；②假设n k =（k ∈N ，且0k n ≥）时命题成立，推导出在1n k =+时命题也成立．用模取余运算：mod a b c =表示“整数a 除以整数b ，所得余数为整数c ”．用带余除法可表示为：被除数＝除数×商＋余数，即a b r c =⨯+，整数r 是商．举一个例子7321=⨯+，则7mod31=；再举一个例子3703=⨯+，则3mod 73=．当mod 0a b =时，则称b 整除a ．从序号分别为0a ，1a ，2a ，3a ，…，na 的1n +个人中选出一名幸运者，为了增加趣味性，特制定一个遴选规则：大家按序号围成一个圆环，然后依次报数，每报到m （2m ≥）时，此人退出圆环；直到最后剩1个人停止，此人即为幸运者，该幸运者的序号下标记为()1,f n m +．如()1,0f m =表示当只有1个人时幸运者就是0a ；()6,24f =表示当有6个人而2m =时幸运者是4a ；()6,30f =表示当有6个人而3m =时幸运者是0a ．（1）求10mod3；（2）当1n ≥时，()()()()1,,mod 1f n m f n m m n +=++，求()5,3f ；当n m ≥时，解释上述递推关系式的实际意义；（3）由（2）推测当1212k k n +≤+<（k ∈N ）时，()1,2f n +的结果，并用数学归纳法证明．。

高考生物专题复习题：细胞的基本结构

高考生物专题复习题：细胞的基本结构一、单项选择题（共6小题）1.洋葱根尖分生区能合成生物大分子的细胞器是（）A．细胞核B．线粒体C．叶绿体D．大液泡2.无机盐在细胞中含量很少，但对于维持细胞和生物体的生命活动都有重要作用。

下列关于无机盐的叙述，错误的是（）A．P是组成细胞膜的元素B．Fe不是构成血红素的元素C．细胞中大多数无机盐以离子形式存在D．哺乳动物血液中Ca2+含量太低会引起抽搐3.核仁是一个处于动态变化的核内结构，其组成成分很不稳定，并且由于细胞类型和生理状态的不同而存在明显的差异。

一般来说，核仁的主要成分包括rDNA、rRNA、蛋白质和一些酶类等。

下列有关核仁的叙述，正确的是（）A．哺乳动物成熟红细胞中的核仁会周期性地消失和重建B．细胞中的遗传信息主要储存在核仁的rDNA中C．核仁中的蛋白质、酶类是在核仁中合成的D．胰腺细胞中的核仁比口腔上皮细胞中的核仁大4.迁移体是我国发现的具有单层膜的新细胞器，呈囊状结构，能识别受损线粒体并将其转运到迁移体内，再将受损线粒体运送到细胞外，以维持细胞的稳态。

下列有关叙述错误的是（）A．可用差速离心法分离迁移体等细胞器B．迁移体膜的主要成分是脂质和蛋白质C．迁移体的膜不属于细胞的生物膜系统D．受损线粒体的转运需依赖膜的流动性5.下列有关教材实验方法或技术的叙述，错误的是（）A．证明细胞膜的流动性常用荧光标记法B．同位素标记法可用于研究分泌蛋白的分泌途径C．分离细胞中的各种细胞器采用的密度梯度离心法D．核移植技术可用于研究细胞核的功能6.下面为与细胞相关的一些现象：①脂溶性物质极易通过细胞膜，并且细胞膜很容易被脂溶性物质所溶解；②细胞的表面张力明显低于油—水界面的表面张力（油脂滴表面若吸附有蛋白质成分表面张力会降低）；③用清水清洗刚采摘的红苋菜时清水不呈红色，将红苋菜置于沸水中一段时间后，汤呈红色；④人的成熟红细胞中全部磷脂分子铺成单分子层后的面积约为细胞膜表面积的两倍。

高考生物专题复习题：遗传的分子基础

高考生物专题复习题：遗传的分子基础一、单项选择题（共6小题）1.核糖核酸酶P是一种催化tRNA前体加工的核糖核酸-蛋白复合物，核糖核酸酶P（）A．与tRNA的组成元素不同B．能水解产生核糖核苷酸和氨基酸C．仅存在于真核细胞中D．催化水解碱基与核糖间的化学键2.大肠杆菌核糖体蛋白与rRNA组装成核糖体。

当大肠杆菌细胞中缺乏足够的rRNA时，核糖体蛋白可通过结合到自身mRNA上的核糖体结合位点，抑制自身mRNA的翻译。

下列叙述错误的是（）A．大肠杆菌核糖体蛋白的基因转录完成后再翻译B．同一个核糖体合成的蛋白质种类可能不同C．核糖体与mRNA结合后逐次阅读遗传信息，直至读取到终止密码子结束D．核糖体蛋白的结合特点，维持了RNA和核糖体数量平衡，减少了物质与能量浪费3.绝大多数生物的遗传物质都是DNA。

下列关于DNA结构的叙述，正确的选项是（）A．DNA双螺旋结构模型中，A—T碱基对与G—C碱基对的直径不同B．DNA的多样性体现在每一个DNA分子都有特定的碱基对排列顺序C．DNA分子中A—T碱基对所占的比值越大，其热稳定性越高D．T2噬菌体的遗传物质中嘌呤碱基数目与嘧啶碱基数目相等4.为了探究生物遗传物质的本质是蛋白质还是DNA，赫尔希和蔡斯利用放射性同位素35S和32P，分别标记T2噬菌体的蛋白质和DNA，并让其去侵染大肠杆菌。

下列关于该实验的叙述，正确的是（）A．可以用14C和18O代替35S和32P对T2噬菌体进行标记B．35S组的子代噬菌体不含35S，说明蛋白质不是遗传物质C．用标记好的T2噬菌体去侵染肺炎链球菌可得到相同的结论D．整个实验中在标记噬菌体阶段，需用含35S或32P的培养基培养大肠杆菌5.在不同类型的细胞中，有些基因在所有细胞中都表达，有些基因只在某类细胞中特异性表达。

下列相关叙述错误的是（）A．ATP合成酶基因在所有细胞中都表达B．输卵管细胞中可检测到血红蛋白mRNAC．细胞的分化取决于基因的表达及其调控D．基因通过其表达产物来控制生物的性状6.列关于DNA分子结构的叙述，错误的是（）A．DNA分子的热稳定性与C—G碱基对的比例有关B．不同DNA分子中的碱基配对方式存在差异C．环状DNA分子中的每个五碳糖都同时连接2个磷酸基团D．一个DNA分子每条单链中A+T占该单链全部碱基比值一般相同二、多项选择题（共4小题）1.碱基家族添了新成员，科学家合成了P、B、Z、S四种新的碱基，它们的配对原则是Z配P，S配B，并都是通过三个氢键连接。

初中英语专题复习语法测试题(含答案)

初中英语专题复习语法测试题(含答案)一、单项选择题（共10小题，每小题1分，满分10分）1. — _______ does your father go to work every day?— By bus.- A. How B. When C. Where D. Why2. Linda _______ to music while she does her homework. She thinks it helps her concentrate.- A. is listening B. listens C. listened D. will listen3. I can't believe ________ good grades Amy always gets in all her subjects.- A. what B. how C. why D. when- A. will B. would C. did D. do5. — How much ________ the shoes?— They ________ 200 yuan.- A. are / are B. do / cost C. is / cost D. does / cost6. The teacher asked us ________ so much noise in the classroom.- A. don't make B. didn't make C. not make D. not to make7. Peter ________ across the street when the accident happened.- A. is walking B. was walking C. walks D. walked8. We ________ our English test tomorrow, so we must study hard tonight.- A. will have B. has C. are having D. were having9. My little sister enjoyed ________ in the lake during the summer vacation.- A. swim B. to swim C. swimming D. swam10. — _______ you finish your homework yet?— No, not yet. I'm still working on it.- A. Did B. Have C. Do D. Will答案1. C2. B3. B4. B5. C6. D7. B8. A9. C 10. C二、完形填空（共10小题，每小题1分，满分10分）从下列单词中选择适当的词并用其正确形式填空，使短文意思完整、正确。

高考生物专题复习题：群落

高考生物专题复习题：群落一、单项选择题（共6小题）1.群落是一定时空条件下不同物种的天然群聚。

根据群落的外貌和物种组成等方面的差异，可以将陆地的群落分为不同类型。

在不同的群落中，生物适应环境的方式不尽相同。

以下关于群落的叙述正确的是（）A．荒漠生物群落中的爬行动物往往以尿素的形式排泄含氮废物B．森林生物群落中的阴生植物叶绿体颗粒小，呈浅绿色C．全年高温，湿润的热带雨林中乔木往往有板状根，树的分支发达D．分布于我国华北等地的落叶阔叶林树冠发达，林冠往往整齐；芽具有鳞片，树皮厚2.采用稻田养蟹的生态农业模式既可提高水稻产量又可收获螃蟹。

下列叙述错误的是（）A．该模式中水稻属于第一营养级B．该模式中水稻和螃蟹处于相同生态位C．该模式可促进水稻对二氧化碳的吸收D．该模式中碳循环在无机环境和生物间进行3.分层现象是群落研究的重要内容。

下列关于森林群落分层现象的叙述，正确的是（）①森林群落的分层现象提高了生物对环境资源的利用能力②森林植物从上到下可分为不同层次，最上层为灌木层③森林群落中植物的分层现象是自然选择的结果④森林植物只有地上分层现象，没有地下分层现象⑤森林群落中动物的分层现象与栖息空间和食物有关⑥群落中植物垂直分层现象的形成是由动物种类决定的A．①③④B．①③⑤C．③⑤⑥D．②④⑥4.荒漠中生活着的植物主要有仙人掌植物、骆驼刺属植物等，动物主要是爬行类、啮齿目、鸟类、昆虫等。

下列关于荒漠生物群落的叙述，正确的是（）A．进入雨季后，群落中会出现一些生长、繁殖周期很短的植物，体现了群落的季节性B．研究爬行类动物蜥蜴的生态位，只需要研究它的洞穴分布、主要食物来源、天敌C．荒漠生物群落中生存的植物普遍矮小且稀疏，只具有水平结构，不具有垂直结构D．匍根骆驼蓬数量最多，因此是荒漠生物群落中的优势种，这种优势是可以改变的5.牯牛降北坡从山麓到山顶依次出现常绿阔叶林、常绿落叶阔叶混交林、针阔叶混交林、针叶林、山地草丛。

高考生物专题复习题：基因工程

高考生物专题复习题：基因工程一、单项选择题（共6小题）1.PCR引物的3′端有结合模板DNA的关键碱基，5′端无严格限制，可用于添加限制酶切点等序列。

下列相关叙述错误的是（）A．图中两条子链合成一定都是从5′端向3′端延伸B．图示表示复性阶段，该过程的温度与引物的长短有关C．用图示引物扩增5次后，可以产生22个目标产物D．PCR每次循环都消耗引物和原料，在实验过程中需要及时补充2.CRISPR/Cas9基因编辑技术可简单、准确地进行基因定点编辑。

其原理是由一条单链向导RNA引导核酸内切酶Cas9到一个特定的基因位点进行切割。

通过设计向导RNA中20个碱基的识别序列，可人为选择DNA上的目标位点进行切割（如下图）。

下列相关叙述错误的是（）A．合成Cas9蛋白需要mRNA、tRNA、rRNA参与B．向导RNA分子中不存在碱基互补配对C．Cas9蛋白通过作用于磷酸二酯键对目标DNA进行切割D．识别序列选择切割位点的原理是碱基互补配对原则3.下列有关基因工程技术的叙述，正确的是（）A．重组DNA技术所用的工具酶是限制酶、DNA聚合酶和运载体B．基因工程是在细胞水平上进行设计和操作的C．只要目的基因进入受体细胞，就能成功实现稳定存在和表达D．选细菌为重组质粒受体细胞，是因为质粒易进入细菌，且繁殖快4.下列关于DNA片段扩增及电泳鉴定实验的说法，错误的是（）A．放入PCR仪前，需要对离心管进行离心，使反应液集中在底部B．配置琼脂糖溶液时，需要根据DNA片段的大小调节琼脂糖浓度C．电泳时需要的两种缓冲液分别含有核酸染料和指示剂D．电泳时，需要根据电泳槽阳极至阴极之间的距离设定电压5.下列关于“DNA的粗提取与鉴定”实验的叙述，错误的是（）A．利用DNA不溶于酒精溶液，而某些蛋白质能溶于酒精溶液，可将DNA 与蛋白质分离B．将实验材料的研磨液倒入离心管中，离心后取沉淀物备用C．在用预冷的酒精沉淀DNA时，要用玻璃棒沿一个方向搅拌，防止DNA 断裂D．利用DNA能溶于2mol/LNaCl溶液的原理，可将提取的丝状物或沉淀物溶解于其中6.下列有关目的基因导入受体细胞和检测与鉴定的叙述，正确的是（）A．用Ca2+处理植物细胞有利于重组Ti质粒的导入B．对目的基因进行扩增时，通过荧光标记技术实时定量测定产物的量C．将某种药用蛋白基因导入动物乳腺细胞中可获得乳腺生物反应器D．验证转基因抗虫棉是否成功时，通过RNA分子标记检测目的基因是否表达二、多项选择题（共4小题）1.科学家将苏云金杆菌中的Bt 基因（抗虫基因）利用农杆菌转化法导入棉花的愈伤组织细胞，并进行组织培养获得棉花植株。

高考生物专题复习：基因位于染色体上

高考生物专题复习：基因位于染色体上一、单项选择题（共10小题）1．著名生物学家萨顿提出：基因是由染色体携带着从亲代传递给下一代的，他得出此推论采用的方法是（）A．归纳法B．假说—演绎法C．类比推理D．模拟实验法2．下列关于基因、基因型、染色体的叙述正确的是（）A．萨顿利用假说—演绎法证明了基因位于染色体上B．体细胞中的基因成对存在，配子中只含一个基因C．染色体是基因的载体，所有基因都位于染色体上D．基因在染色体上呈线性排列3．下列有关基因与染色体的叙述中正确的是（）A．具有同型性染色体的生物发育成雌性个体，具有异型性染色体的生物发育成雄性B．含X染色体的配子是雌配子，含Y染色体的配子是雄配子C．位于X染色体或Y染色体上的基因，在遗传上总是与性别相关联D．真核细胞的基因都位于染色体上，且呈线性排列4．下列关于染色体和基因的叙述错误的是（）A．性染色体上的基因所控制的性状遗传总是和性别相关联B．同源染色体上的基因的遗传不符合孟德尔的自由组合定律C．减数分裂中细胞内核基因的行为和染色体的行为一致D．摩尔根是第一个用荧光将基因定位在染色体上的科学家5．孟德尔豌豆杂交实验和摩尔根果蝇杂交实验，F2出现差异的原因是（）A．前者有基因分离的过程，后者没有B．前者使用了假说—演绎法，后者没使用C．前者相对性状的易于区分，后者不易区分D．前者体细胞中基因成对存在，后者不一定6．某种昆虫长翅（R）对残翅（r）为显性，直翅（M）对弯翅（m）为显性，有刺刚毛（N）对无刺刚毛（n）为显性，控制这3对性状的基因均位于常染色体上。

现有这种昆虫一只，其基因型如图所示。

下列相关说法正确的是（）A．长翅与残翅，直翅与弯翅这二对相对性状的遗传遵循基因自由组合定律B．该昆虫产生的卵细胞的基因型有8种C．对该昆虫进行测交实验，子代表型有四种D．该昆虫与相同基因型的昆虫交配，后代中与亲代表型相同的概率为1/4 7．下列关于基因与染色体关系的说法中，正确的是（）A．萨顿通过类比推理的方法证明基因就在染色体上B．染色体上的非等位基因都可以在减数第一次分裂后期自由组合C．摩尔根等人用荧光分子标记法测出基因在染色体上呈线性排列D．白眼雄果蝇与杂合雌果蝇杂交结果不能证明眼色基因只在X染色体上8．萨顿依据“基因和染色体的行为存在明显的平行关系”，提出“基因是由染色体携带着从亲代传递给下一代”的假说，下列说法中，不属于他所依据的“平行”关系的是（）A．以染色体为载体的DNA，能进行复制B．基因和染色体在体细胞中都是成对存在，在配子中都只有成对中的一个C．非同源染色体上的非等位基因在形成配子时自由组合，非同源染色体在减数分裂中也有自由组合D．基因在杂交过程中保持完整性和独立性，染色体在配子形成和受精过程中，也有相对稳定的形态结构9．下列有关基因和染色体的叙述，错误的是（）①非等位基因都位于非同源染色体上②摩尔根利用果蝇进行杂交实验，运用“假说一演绎”法确定了基因在染色体上③染色体是基因的主要载体，基因在染色体上呈线性排列④一条染色体上有许多基因，染色体就是由基因组成的⑤萨顿研究蝗虫的减数分裂，提出假说“基因在染色体上”A．①②⑤B．②③④C．①④D．②③⑤10．以下说法正确的是（）A．基因在染色体上的提出者是摩尔根B．基因与染色体的行为存在平行关系C．控制果蝇白眼的基因在Y染色体上也有等位基因D．一条染色体上只有一个基因二、综合题（共5小题）11．萨顿提出“染色体可能是基因的载体”的假说，摩尔根起初对此假说持怀疑态度，他和同事设计果蝇杂交实验对此进行研究，杂交实验如图1所示，图2是果蝇的染色体模式图。

人教版英语八下期中复习专题单项选择（含解析）

人教版英语八下期中复习专题单项选择（含解析）人教版英语八下期中复习专题——单项选择（含解析）一、单项选择(每小题1.5分, 共15分)1. The air in the morning is so fresh here that I ________ early to exercise.A. get upB. get onC. get offD. get down2. —Jack, you swam very well. Who taught you?—Nobody. I taught ________.A.IB. meC. myselfD. mine3. I don't have much money, but I'd like to buy my dad something reallyspecial, if you know what I ________.A. wantB. careC. meanD. prefer4. —My mother was badly ill in hospital yesterday. I had to look after her,so I didn't go to have the picnic.—________.A. Never mindB. I am sorry to hear thatC. No problemD. Good luck5. ________ our surprise, Larry came here earliest today.A. ToB. WithC. WithoutD. In6. You look too tired. You ________ rest and ________work too hard.A. should; shouldB. shouldn't; shouldn'tC. shouldn't; shouldD. should; shouldn't7. Lucy is used ________ a walk after dinner.A. to takeB. takingC. to takingD. take8. Did you agree ________ a party for him?A. hasB. to haveC. haveD. had9. Please let me tell you again ________ you won't forget.A. as long asB. ifC. so thatD. because10. He drove so fast at the turn that the car almost went ________ the road.A. offB. onC. alongD. behind二、单项选择(每小题1. 5分, 共15分)1. —Why did he ________ to your life?—Because he taught me a lot. He was my idol.A. make a differenceB. made a differenceC. make a problemD. made a problem2. —Could you please help me ________, Tom? I can't work out the problem.—OK. Let me try.A. outB. upC. withD. after3. The Internet makes________ possible for everyone to get educationanywhere and anytime.A. itB. thisC. thatD. the4. If we want to make the world different, we should ________ ourselves first.A. seeB. noticeC. changeD. raise5. My sister ________ be lazy. But now she works really hard.A. used toB. is used toC. was used toD. were used to6. You could visit the sick people in the hospital to ________.A. cheer up himB. cheer him upC. cheer up themD. cheer them up7. Larry wants to fix up these bikes and ________ to the poor children.A. give away themB. give away itC. give it awayD. give them away8. —Dad, shall I do my homework tomorrow?—Better not, dear. Don't ________ what you can do today till tomorrow.A. put onB. put offC. put outD. put up9. —You should do what you can ________ your English, Li Ming.—OK, I will. Thank you, Ms. Hu.A. improveB. to improveC. improvingD. improved10. Luckily, I arrived home before it________.A. rainsB. is rainingC. rainedD. will rain三、单项选择(每小题1. 5分, 共15分)1. —What would you like, pork or fish?—________. I prefer chicken.A. EitherB. NeitherC. BothD. Each2. —Could you go swimming with me this afternoon, Jane?—________, but I have to do the chores first.A. I'd like toB. Of course notC. I don't mindD. It's nothing3. —What does Huawei's newest smartphone look like?—It's wonderful! You can ________ it in half just like closing a book.A. handB. passC. foldD. cut4. Susan's mother was very happy today, because Susan ________ herlittle brother when she wasn't at home.A. agreed withB. depended onC. worked onD. took care of5. She got up early this morning ________ catch the first bus.A. in order toB. because ofC. in order thatD. so to6. —Where do you usually have lunch?—In the school dining hall. It ________ different kinds of food ________ us.A. sends; toB. provides; forC. adds; toD. shares; with7. —There was the thick haze(雾霾) in our city this spring. What doyou think of it?—I think________cars we drive, ________pollution our city will have.A. the fewer; the fewerB. the fewer; the lessC. the more; the fewerD. the more; the less8. —Jack, have you done the survey?—Not yet. I am in New York now. I'll finish it ________ I come back.A. wheneverB. as soon asC. beforeD. because9. I'm sure there is no need ________ you ________ with such a young man.A. of; to talkB. of; talkingC. for; talkD. for; to talk10. I can't play the guitar, and________.A. neither can my sisterB. my sister can't, tooC. so can't my sisterD. can my sister, either四、单项选择(每小题1. 5分, 共15分)1. —What's wrong ________ you? You look unhappy.—My mother makes me do my homework instead of watching Operation Red Sea.A. fromB. withC. ofD. to2. —Did they make a decision at last?—No. Everyone had a different ________ about the plan. We need to have another discussion.A. opinionB. interestC. memberD. relation3. Jenny is afraid to travel by plane. She always feels ________ when getting on it.A. nervousB. interestedC. relaxedD. happy4. Please ________ this picture with that one, and then tell me thedifferences between them.A. compareB. adviseC. explainD. return5. Never put off ________ tomorrow what you can do today.A. untilB. beforeC. whenD. as6. I'm going to take him to some famous hutongs ________he can learnmore about China.A. becauseB. whenC. so thatD. even though7. Attention, please! Without permission, children are not allowed________ alone here.A. to swimB. swimmingC. swimD. swam8. —I ________ my best friend yesterday morning.—Why not call her up and say sorry to her?A. depended onB. looked forC. hung out withD. argued with9. The math problem is very difficult. I can't ________. Could you give me a hand?A. work it outB. work out itC. cut it outD. cut out it10. —Our team lost the basketball game and I feel very sad.—________. I believe you can do better next time.A. It's rightB. It's excitingC. It's not a big dealD. It's nota good idea五、单项选择(每小题1. 5分, 共15分)1. There was no ________ in the old house. So I could see nothing.A. windB. lightC. woodD. cloud2. —Why did Jim sit in ________ when other students discussed theproblem?—Because he knew nothing about it.A. discussionB. troubleC. orderD. silence3. The rain beat ________ the window heavily and the little girl was veryafraid.A. fromB. withC. throughD. against4. We decided not to climb the mountain because it was raining________.A. heavilyB. stronglyC. hardlyD. nearly5. More and more people ________ the importance of the eco-friendlylifestyle.A. missB. promiseC. realizeD. suggest6. My sister ________ her keys in the classroom.A. leftB. lookedC. forgotD. gave7. ________ I was talking on the telephone, David came in.A. BecauseB. WhileC. IfD. Although8. Let's keep ________ hard until we succeed.A. to workB. workC. worksD. working9. The news on the radio ________ that the strongest rainstorm may be inthe area we live in.A. toldB. reportedC. knewD. spoke10. He said he ________ to draw a plane on the blackboard at that time.A. triesB. triedC. was tryingD. will try一、单项选择(每小题1. 5分，共15分)1. (新题)—Do you know Wu Minxia?—Yes. She was an excellent diver before. She married ________ Zhang Xiaocheng in 2017.A. withB. forC. /D. on2. Although ________ helped him, he was successful in the end.A. somebodyB. anybodyC. nobodyD. everybody3. —Mom, I want to drive to my grandparents' home.—Don't be ________. You are too young to drive.A. sillyB. noisyC. nervousD. sad4. —How shall we go to the park this time?—Let's go there on foot ________ taking a bus.A. insteadB. instead ofC. becauseD. because of5. —What was the weather like yesterday?—It was ________ cold and windy.A. a fewB. a bit ofC. a little bitD. a kind of6. Lucy often ________ me ________ my best friend. They both have long curly hair.A. thinks; ofB. reminds; ofC. helps; outD. leaves; out7. —The math problem is too difficult.—Don't worry! Let's find a good way ________ it.A. to solveB. solveC. solvingD. to solving8. The popular TV program ________ five years ago.A. hung outB. went outC. came outD. ran out9. When you are in your school dining hall during lunchtime, you mayfeel lonely ________ you can find someone to have lunch with.A. ifB. unlessC. afterD. because10. —Can you tell me when you are going to arrive there?—I'm not sure. But I'll ring you up as soon as I ______ there tomorrow.A. arriveB. arrivedC. will arriveD. am going to arrive参考答案一、1.A解析：句意为“这儿早晨的空气如此清新，以至于我早早起床去锻炼”。

中国现代文学专题复习资料

现代文学专题复习资料一、单项选择题1. 1919年初，北京大学傅斯年、罗家伦等学生创立了( )。

A．青年杂志社 B．新潮社C．文学研究会 D．创造社2. 19 21年诗集《女神》出版，宣告了新诗的最终形成。

《女神》的作者是( )。

A．郭沫若 B．胡适C．刘半农 D．鲁迅3. 30年代中期，郁达夫移居杭州之后，是他游记散文创作的高峰期，除《达夫游记》外，还创作有( )等。

A．《漂泊杂记》 B．《屐痕处处》C．《西湖漫拾》 D．《湖上散记》4．田汉1920年创作完成的第一部剧本是( )。

A．《获虎之夜》 B．《梵峨嶙和蔷薇》C．《名优之死》 D．《咖啡店之一夜》5．“七月派”中最优秀的小说家是( )。

A．胡风 B．阿垅C．路翎 D．穆旦6．奠定凌叔华文坛地位的成名作是1925年1月10日在《现代评论》（第一卷第五期）上发表的( )。

A．《绣枕》B．《女儿身世太凄凉>C．《酒后》D．<资本家之圣诞》7．新诗史上第一部歌颂苏联十月革命和社会主义新生活的诗集是( )。

A．《女神》 B．《新梦》C．《前茅》 D．《恢复》8．七月诗派重要的诗论家是著有<诗与现实》、《人与诗》、《诗是什么》的( ’)。

A．田间 B．胡风C．艾青 D．阿垅9．私淑里尔克的一位中国诗人，以他取得的巨大成绩成就了他在文学史上诗哲的地位，他的《十四行集》，占据了40年代诗歌史上的第一座高峰，这位诗人是( )。

A．冯至 B．卞之琳C．穆旦 D．艾青10.得到“反映农村斗争的最杰出的作品”、“解放区文艺的代表之作”等高度评价的赵树理小说是( )。

A．《小二黑结婚》B．《李家庄的变迁》C．《李有才板话》D．《三里湾》二、多项选择题11．湖畔诗社诗人汪静之出版的个人诗集主要有( )等。

A．《湖畔》 B．《春的歌集》C．《蕙的风》 D．《寂寞的国》12. 40年代的“太平天国史剧”系列主要有( )等。

A.《金田村》 B．《李秀成之死》C．《孔雀胆》 D．《忠王李秀成》13．与蒋光慈作品风格相近的革命小说主要有( )等。

七年级七年级英语单项选择（50题）期末复习专题练习及答案

七年级七年级英语单项选择（50题）期末复习专题练习及答案一、选择题1．Living in_________ ever increasingly fast-paced world, we are facing greater competition, so we must take _________ advantage of every opportunity to develop.A．an; the B．an; /C．the; an D．the; /2．Being able to afford_____drink would be _____comfort in those tough times.A．the;theB．a;aC．a;/D．/;a3．Mr. Smith, ________ headmaster of the school, told us, "________ sixth of students here go on to study at Oxford and Cambridge."A．/; A B．/; The C．the; The D．a; A4．He was walking along the beach. All of _____ sudden, he saw a beautiful girl dancing ______ music.A．a; with B．/ ; withC．/ ; to D．a ; to5．---- I am afraid I have got _______ headache.---- So please stay in ________ bed for a few more hours.A．a, the B．the, a C．\, a D．a, \二、选择题6．— Who was calling you on the phone just now?— ________ was my mum.A．She B．That C．It D．This7．Life is like a one-way street. ________ will happen________ the same way again. A．Nothing； by B．Nothing；/ C．None； in D．None；on 8．—Do you have ________else to say for your mistake?—________but sorry.A．anything; Something B．something; EverythingC．anything; Nothing D．something; Anything三、选择题9．Cindy is always full of __________ because she takes a lot of exercise everyday. A．courage B．knowledge C．energy D．experience 10．—Have you heard of a new technology about TV?—Yes. It’s “8K TV”. I believe that it will make a great ________ to people’s life.A．surprise B．progress C．difference D．choice四、选择题11．—We must study hard to enter our ideal high school.—Exactly! Just as President Xi says,“Happiness is achieved ________ hard work.”A．through B．across C．along D．with 12．—Hi, Mom directed by Jia ling is a hit ________ this year.—It really is. It shows us the deep love between a mother and a daughter.A．/ B．in C．on D．at13．________ Friday afternoon, our school ends earlier than usual.A．At B．On C．To D．In五、选择题14．—How do you like my new dress?—Well, if I ________ say, it is not suitable for you.A．may B．must C．have to D．should15．— Mum, why do I have to wash hands so many times a day?—You ________ be too careful, for your health.A．can’t B．mustn’t C．may not D．needn’t 16．—In China, many students have to stay up late to do their homework.—No worries. The government has realized the problem. I’m sure th ere ________ be good news soon.A．can B．should C．must D．need17．It’s amazing that the pen ________turn voice into text with few mistakes.A．can B．must C．may D．need六、选择题18．________ unusual music he is playing! All of us are losing ourselves in it.A．How B．What a C．What D．How a19．— _________ crowded Guanqian Street is!— Yes, because the number of people has kept _________ greatly since 1990.A．What; rising B．How a; raising C．What; raising D．How; rising七、选择题20．— ________ orange juice does she need?— Just a little.A．How much B．How long C．How many D．How far 21．—___________ will the project of Wuxi Metro Line 3 be completed?—It won't take long. Just in about three months.A．How long B．How far C．How soon D．How often八、选择题22．The school hall ________ next week to celebrate this year's Science & Technology Festival. A．is decorated B．will decorate C．is decorating D．will be decorated 23．—The film Coco ________ with the Oscar Award not long ago.—That’s great! It deserves such a high prize.A．presents B．presented C．is presented D．was presented 九、选择题24．Today many physical bookstores down with financial difficulties, inflexible management strategies and competitive pressure from online bookstores.A．had closed B．having closedC．being closed D．are closing25．Chinese people’s spending on overseas trips ______ year by year.A．had risen B．riseC．is rising D．rose26．--The concert won’t start till seven. Why____ so early?--You know I don' t want to be at the traffic there. It’s terrible during the rush hour.A．are you leaving B．do you leaveC．were you leaving D．had you left27．—Tom, what’s your sister doing?— She ________ her homework in the study.A．does B．will do C．did D．is doing 28．Betty can’t join us in the card game. She ________ the classroom.A．has cleaned B．was cleaning C．has cleaned D．is cleaning 29．—What’s that noise, Sam?— My little brother ________ his toy car.A．played B．is playing C．plays D．was playing 十、选择题30．Hurry up, _______ we’ll be late for the first bus.A．and B．but C．so D．or31．Would you like to go to the museum with me?I’d love to, ______ I’m afraid I have no time.A．but B．and C．or D．so32．—I don’t like reading ______ watching TV. What about you?—I don’t like reading all day , ______ I like watching TV news.A．and ; or B．and ; and C．or ; and D．or ; but 33．Put your books in the drawer, _____ they won’t get lost.A．or B．and C．but D．so十一、选择题34．—Could you please tell me ________?—Next Thursday morning.A．when we visited the Capital Museum B．when did we visit the Capital Museum C．when we will visit the Capital Museum D．when will we visit the Capital Museum 十二、选择题35．—I spent the whole night preparing my report.—Don’t stay up too late, or you will be tired out. Remember, .A．it never rains but it poursB．yo u can’t burn the candle at both endsC．you can’t put all your eggs in one basketD．the grass is always greener on the other side十三、选择题36．—I visited the Purple Mountain Observatory by myself last Saturday.—________ Why didn’t you tell me earlier?A．You did? B．I hope not. C．Have a good time. D．I can’t believe it.十四、选择题37．________ with life in the city, life in the countryside is much slower and more peaceful. A．To compare B．Comparing C．Compared D．Compare 38．Your hair is too long. You’d better _____.A．have it cut B．have cut it C．be cutting it D．to cut it 39．People are advised to avoid ________ their eyes, nose, and mouth with unwashed hands. A．touch B．touched C．to touch D．touching 40．—What do you remember about Grade 7?―I remember________a prize in the s chool writing competition.A．to win B．win C．winning D．won 41．—Anyone shouldn’t _________ use fire outdoors.—Yeah, and we should pay attention to ________ our forests and grasslands.A．be allowed to; protect B．allow to; protectingC．be allowed to; protecting D．allow to; protected42．Sally practices _________ the guitar very hard for the coming contest next month. A．play B．plays C．playing D．to play 43．—To keep the students safe on their way to school, we have taken more action.— That sounds great. We should do what we can __________ the school bus accident.A．to prevent B．prevent C．to preventing D．preventing十五、选择题44．China’s high-speed railways ________ from 9, 000 to 35, 000 kilometers in the past few years.A．are growing B．were growing C．will grow D．have grown 45．What a pity! My new computer__________ a virus and it can't work now.A．catches B．caught C．is caught D．has caught 46．My mother is a teacher. She ________ English in our school since she graduated from university.A．taught B．has taught C．is teaching D．will teach47．With the wide use of e-business, the way of shopping we were used to a lot. A．change B．changing C．changed D．has changed十六、选择题48．Our class _______ forty-five students, in other words, forty-five students ______ our class. A．consists of, are made up of.B．is consisted of, make up.C．consists of, make up.D．is consisted of, are made up of.49．Whenever you ______ a present, you’d better think about it from the receiver’s preference. A．bought B．buy C．will buy D．have bought 50．Candy has decided to move to Taipei next year. When she studies in an art school there, she ________ with her aunt for five months.A．lives B．lived C．has lived D．will live【参考答案】***试卷处理标记，请不要删除一、选择题1．B解析：B【解析】试题分析：考查冠词：第一空填an，生活在一个快节奏的世界，单词even以元音字母e开头，所以是an；第二空不填，固定词组take advantage of意思“利用”，句意：生活在一个快节奏的世界，我们面对较大的竞争，因此我们必须利用每个机会去发展。

高考生物专题复习题：生物的进化

高考生物专题复习题：生物的进化一、单项选择题（共5小题）1.雄性海龙鱼承担育儿责任，其具有细长管状嘴和育雏袋等。

相关叙述错误的是（）A．突变和基因重组为海龙鱼的进化提供原材料B．雄性海龙鱼细长管状嘴和育雏袋的出现是适应的表现C．雄性海龙鱼承担育儿责任是雌雄个体长期协同进化的结果D．深海环境相对稳定，海龙鱼的进化速度相对较慢2.某个蜂鸟种群中鸟的喙有长而弯和短而直两种类型。

长弯喙蜂鸟适于在略弯曲的长筒状花柱中采蜜，短直喙蜂鸟则适于在短小笔直的短筒状花柱中采蜜；尽管长弯喙蜂鸟也可以取食短筒状花中的蜜，但它们更偏爱长筒状花。

下列叙述正确的是（）A．若短小笔直的花灭绝，在长筒状花的选择下短喙蜂鸟的喙会定向突变为长而弯的喙B．长弯喙蜂鸟和短直喙蜂鸟的差异体现了生物多样性中的物种多样性C．即使蜂鸟发生了有害的基因突变，也可能为其生物进化提供原材料D．蜂鸟之间，蜂鸟与其他物种之间，蜂鸟与环境之间都存在协同进化3.可遗传变异、自然选择和隔离是物种形成的重要环节，下列叙述正确的选项是（）A．交配后能产生可育后代的个体一定不存在隔离B．生物的变异一定会引起种群基因频率的改变和生物进化C．具有有利变异的个体，都能成功地生存并繁殖后代D．种群中一些个体发生基因突变，使种群基因频率改变，说明种群发生了进化4.大量证据表明生物都有共同的祖先，下列不支持该论点的证据的是（）A．人和鱼的胚胎发育早期都有鳃裂和尾B．所有生物的生命活动都是靠能量驱动的C．具有细胞结构的生物的遗传物质都是DNA，且共用一套遗传密码D．鲸的鳍、猫的前肢和人的上肢等“同源器官”结构相似5.达尔文认为各种适应性特征的形成来源于微小的有利变异的逐渐积累。

下列叙述正确的是（）A．适应就是指同种生物之间、生物与环境之间都有适应B．可遗传的有利变异和环境的定向选择是适应形成的必要条件C．达尔文认为适应的来源是获得性遗传，适应是自然选择的结果D．经多变的环境诱发产生可遗传变异的个体大都更加适应新环境二、多项选择题（共2小题）1.现有1000只某品种的昆虫迁入某岛屿中，其中基因型为AA的个体有550只，基因型为Aa的个体有300只，基因型为aa的个体有150只，昆虫个体进行自由交配，且每只昆虫的繁殖能力相同。