高中选修7英语课后题

第一篇：高中选修7英语课后题

高中选修7英语课后题一

一、单词拼写

1.All of us should be concerned with public _____（事务）to make our society a better one.2.Nowadays people have to pass various tests for professional _____（证书）so that they can be qualified for a well-paying job.3.He may be good at football, but he is very _____(笨拙)on the dance floor.4.When human friends desert us, good books are always ready to give us friendship, sympathy and e_____.5.The foundation would like to launch programs for providing _____(援助)for poor areas and for disease control and prevention in Africa.6.I hope we will have the strength to bear the difficulties and disappointments and bear them with _____(尊严)and without self-pity.7.He is a well-edacuted man and behaves _____(高雅).8.Do you believe that the photo-electric reader be capable of s_____ characters at the rate of two thousand a second?

9.Not everyone think it is ridiculously _____(荒谬的)to predict that the sun will not rise tomorrow.10.It is reported that a couple who separated after 40 years of m_____ split their house in two.11.I want an e_____ for why you have refused to eat these nice fresh cod.12.---I heard that your brother got d_____.Is that true?

---Not so bad,but he dose have problems with his wife.13.F_____ Germany, Einstein went first to France, then to Belgium, and then to Britain.14.In my opinion,this journey, like all the ones mentioned above, was _____(纯粹)imaginary.15.The poor old couple began to regret the _____(购买)of such a large house at so high a price.16.Who will in charge of the distribution of food and clothing to the flood vivtims?

17.We all think that the repairs to the school will be _____(提供资金)by the local educational department.18.Many people thought he should remain and _____(讲课)in Europe to influence society.19.My new boss used to be a travel _____(代理人)in a famous city.20.Life can be compared to a journey with an unknown _____(目的地).二、词语填空

1.This novel,____ TV from the American original, is very popular among young students.2.I know the warning systerm will work well because we have ____ it ____ many times.3.Take heart and wee are sure to ____ these difficulties sooner or later.4.I ____ to see if you were at work but no one answered my phone.5.Just then I heard my name called.____, I found my former English teacher similing at me.6.You must always keep your mind fresh by ____ some time for exercise.7.Hearing the news that he was fired , the young man ____ despair.8.It is time that we ____ and got ready to start out.9.The old man on duty ____ having seen the accused enter the building.10.I don't really work here;I am just ____ until the new secretary arrives.11.It is necessary for us to ____the likely result before we decide to do anything.12.We had several anxious hours waiting for our wet clothes to _____.13.She ____her head from the window and called for help.14.The doctor's advice was that the patient ____ at once.15.I have never done this type of work before;I'm not sure how I will ____.16.It is you teachers’s duty to make the new students ____in your school.17.Here are my reasons for believing I am ____ the position of branch manager

18.At first man ____the places where the food and water were plentiful.19.Why did the president refuse to comment on the election results at the news conference?The symptom of jetlag often persists for several days while the internal body clock slowly ____ the new time zone.三、单句改错

1.The truth is that she did everything she could save her sons from the big fire but in vain.2.We have no choice but work hard to try to find a solution to make sure that we save our economy.3.My English teacher is said to be studying abroad, but I don’t know what country he studied in.4.The doctor noted that the oral drug would significantly reduce the amount of time patients needed being treated.5.As we had had a long walk through one of the markets of Old Delhi, we stopped having a rest at a square.6.I wonder whether the way you thought of making the water clean makes any sense.7.Having stood with great difficulty from the ground, the wounded soldier rushed in the war, never being heard from again.8.On Monday, former Prime Minister Nawaz Sharif also said he wants the vote holding next week.9.The introduction of modern equipment to the company led to a great many workers laid off.10.Tim Bemers-Lee is generally considered to set up the World Wide Web, on which all theinformation is shared by all．

11.Caught cheating in the exam cost him the chance to be promoted.12.He escaped punishing by taking advantage of his position,which caused a bad influence among the citizens.13.We have long known that the reasons why President Bush and his team gave for going to war in Iraq were false

14.The couple saw a new movie at the theatre, after that they had dinner at a Chinese restaurant.15.There is very strong evidencethat the degree in which you maintain your mental faculties depends on a handful of quite simple environmental factors

高中选修7英语课后题二

一、补全句子

1.The young man _____（一心想成为）the general manager of a great enterprise.2.The manager needs an assistant that he can count on to take care of problems _____(在他不在场的情况下).3.The visiting Minister _____(对……表示满意)the talks, _____(补充说)that he had enjoyed his stay here.4.She discovered that there were _____(一堆堆)empty wine bottles _____(形状各导、大小不一)in the corner.5.The young girl _____(险胜)her great rival(对手)in the tennis competition.6.Don’t be angry with them.They only said such unkind things about you _____（出于忌妒）.7.Once he was run after by a seal that was like _____(长着锋利牙齿的巨人)and he was almost _____（当场吓死）.8.This business invitation is _____(出租或出售)of electronic production workshops and related buildings in the IT industry park.9.The moment the 28th Olympic Games _____(宣布开幕), the whole world cheered.10.It is said that dogs will _____(陪伴你)for as long as you want when you are feeling lonely.11.They got home after work only to find the whole house had _____（被弄得乱七八糟）.12.Mary ceremonies will be held to _____（庆祝中华人民共和国成立60周年）next year.13.I hope we can live_____(舒服地)and happ ss in the countryside after we retire.14.The students who fail to _____(符合这些要求)will not be admitted to the famous university.15.It has not been decided _____r(谁接替史密斯先生做我们的导师)?

二、句型转换

1.The new medicine proved beneficial to the patient's skin problems.----The new medicine proved to _____ _____ _____to the patient's skin problems.2.I have neither brothers nor sisters.That is to say, I'm an only child.---I have neither brothers nor sisters—_____ _____ _____, I'm an only child

3.Li Ming has his faults, but, on the whole, he is a good helper

--Li Ming has his faults, but, _____ _____ _____, he is a good helper.4.The manager is busy at his desk.You'd better disturb him.---The manager is busy at his desk.You'd better _____ _____ _____.5.As a matter of fact, my boss is thr years younger than me.--As a matter of fact, my boss is thr years _____ _____ me.6.All we could see in front of us was 200 km of nothing but sand.--All we could see _____ _____ us was 200 km of nothing but sand.7.Did you rewalize that Joe had this problem with his knee?

--____ you ___ that Joe had this problem with his knee?

8.I haven't received any letter from myfather working abroad so far.---I haven't _____ _____ myfather working abroad up to the present.9.We have arranged for her to be treated by a famous doctor of our city.---We have_____ _____ _____ her to be treated by a famous doctor of our city.10.We have become accustomed to the way of living in such a crowded place.---We have _____ _____ _____ the the way of living in so crowded a place.11.It is difficult to imagine that he accepted the decision without any hesitation.---It is hard to imagine _____ _____ the decision without any hesitation.12.The famous scientist will arrive soon and a party will be held in honour of him.---The famous scientist , _____ _____ _____ a party will be held, is to arrive soon.13.It is reported that the floods have left about two thousand people homeless.---The floods _____ _____ _____ _____ _____ about two thousand people homeless.14.It may rain tomorrow．In that case，we'll have to put off the sports meet till next Saturday．

---It may rain tomorrow, _____ _____ _____，we'll have to put off the sports meet till next Saturday．

15.We've replaced the old adding machine with a computer.---We've _____ the old adding machine _____ a computer.三、翻译

1.我以为他在取笑我,就越发跑得快起来,到达学校时我都上气不接下气了。（make fun of;out of breath）

2.我们许多人很少或没有与残疾人工作或交往的经验，因此可能意识不到他们的需求。（disability;aware）

3.就我而言，这两个设计中的后者比前者实际的多。（as far as one is concerned;latter）

4.这位年轻的作家没有文学理论知识，只有吸引观众的愿望。（desire）

5.她年龄还太小，不能不依赖父母；她依靠他们给她提供衣服和食物。（independent；depend）

6.十位专家组成的访问团预定星期四到达，这期间我们该做些什么呢?（due to；in the meantime）

7.我发邮件祝贺他考入清华大学,攻读经济专业。（congratulate；majorg in）

8.有时我们会发现面对面的交流可能是人很尴尬。（embarrass）

9.我确信那儿的自然之美将会给你留下极好的印象。（beauty）

10.我们班所有的学生都渴望参加下月举行的演讲比赛。(be dying to;participate in)

11.人们期待这些年轻人去适应过去几代人从未处理过的社会环境的变化。(adapt to)

12.每年我们都向红十字会捐部分钱以帮助那些贫困中的人。（donate;in need）

13.孩子们在房间里很安静。我纳闷他们在干什么。（up to）

14.在准备发射神舟七号的过程中，科学家需要了解天气变化。(preparation;knowledge)

15.我们不知道那些建筑工人遇到了困难，要不然我们会帮他们的。（otherwise）

第二篇：高二英语选修七课后题

一、单词拼写(20)

1.All of us should be concerned with public _____（事务）to make our society a better one.2.Nowadays people have to pass various tests for professional _____（证书）so that they can be qualified for a well-paying job.3.He may be good at football, but he is very _____(笨拙)on the dance floor.4.When human friends desert us, good books are always ready to give us friendship, sympathy and e_____.5.The foundation would like to launch programs for providing _____(援助)for poor areas and for disease control and prevention in Africa.6.I hope we will have the strength to bear the difficulties and disappointments and bear them with _____(尊严)and without self-pity.7.He is a well-edacuted man and behaves _____(高雅).8.Do you believe that the photo-electric reader be capable of s_____ characters at the rate of two thousand a second?

9.Not everyone think it is ridiculously _____(荒谬的)to predict that the sun will not rise tomorrow.10.It is reported that a couple who separated after 40 years of m_____ split their house in two.11.I want an e_____ for why you have refused to eat these nice fresh cod.12.---I heard that your brother got d_____.Is that true?

---Not so bad,but he dose have problems with his wife.13.F_____ Germany, Einstein went first to France, then to Belgium, and then to Britain.14.In my opinion,this journey, like all the ones mentioned above, was _____(纯粹)imaginary.15.The poor old couple began to regret the _____(购买)of such a large house at so high a price.16.Who will in charge of the distribution of food and clothing to the flood vivtims?

17.We all think that the repairs to the school will be _____(提供资金)by the local educational department.18.Many people thought he should remain and _____(讲课)in Europe to influence society.19.My new boss used to be a travel _____(代理人)in a famous city.20.Life can be compared to a journey with an unknown _____(目的地).二、词语填空(20)

根据句意，选择词语，并用其适当的形式填空。

This novel,____ TV from the American original, is very popular among young students.2.I know the warning systerm will work well because we have ____ it ____ many times.3.Take heart and wee are sure to ____ these difficulties sooner or later.4.I ____ to see if you were at work but no one answered my phone.5.Just then I heard my name called.____, I found my former English teacher similing at me.6.You must always keep your mind fresh by ____ some time for exercise.7.Hearing the news that he was fired , the young man ____ despair.8.It is time that we ____ and got ready to start out.9.The old man on duty ____ having seen the accused enter the building.10.I don't really work here;I am just ____ until the new secretary arrives.11.It is necessary for us to ____the likely result before we decide to do anything.12.We had several anxious hours waiting for our wet clothes to _____.13.She ____her head from the window and called for help.14.The doctor's advice was that the patient ____ at once.15.I have never done this type of work before;I'm not sure how I will ____.16.It is you teachers’s duty to make the new students ____in your school.17.Here are my reasons for believing I am ____ the position of branch manager

18.At first man ____the places where the food and water were plentiful.19.Why did the president refuse to comment on the election results at the news conference?The symptom of jetlag often persists for several days while the internal body clock slowly ____ the new time zone.三、单句改错（15题）

下面句子中，各有一处错误，请改正。

1.The truth is that she did everything she could save her sons from the big fire but in vain.2.We have no choice but work hard to try to find a solution to make sure that we save our economy.3.My English teacher is said to be studying abroad, but I don’t know what country he studied in.4.The doctor noted that the oral drug would significantly reduce the amount of time patients needed being treated.5.As we had had a long walk through one of the markets of Old Delhi, we stopped having a rest at a square.6.I wonder whether the way you thought of making the water clean makes any sense.7.Having stood with great difficulty from the ground, the wounded soldier rushed in the war, never being heard from again.8.On Monday, former Prime Minister Nawaz Sharif also said he wants the vote holding next week.9.The introduction of modern equipment to the company led to a great many workers laid off.10.Tim Bemers-Lee is generally considered to set up the World Wide Web, on which all theinformation is shared by all．

11.Caught cheating in the exam cost him the chance to be promoted.12.He escaped punishing by taking advantage of his position,which caused a bad influence among the citizens.13.We have long known that the reasons why President Bush and his team gave for going to war in Iraq were false

14.The couple saw a new movie at the theatre, after that they had dinner at a Chinese restaurant.15.There is very strong evidencethat the degree in which you maintain your mental faculties depends on a handful of quite simple environmental factors

答案

一、单词拼写(20)

1.affairs 2.certificates 3.clumsy 4.encouragement 5.assistance 6.dignity 7.elegantly

8.scanning 9.absurd 10.marriage 11.explanation 12.divorced 13.Fleeing

14.purely 15.purchase 16.distribution 17.financed 18.lecture 19.agent 20.destination

二、词语填空(20)

1.adapted for 2.tested;out 3.smooth away 4.rang up 5.Turning aroud 6.setting aside 7.abandoned himself to.8 packed up 9.witnessed to 10.helping out

11.reflect on 12.dry out 13.stuck out 14.be operated on 15.fit in 16.feel at home

17.qualified for 18.settled in 19.comment on 20.adjusts to

三、单句改错（15题）

1.save改为 to save 2.work 改为 to work

3.be studying 改为 have studied 4.being改为to be

5.having 改为 to have 6.making 改为 to make

7.never being 改为never to be 8.holding 改为 to be held

9.workers后加being 10.to set 改为 to have set

11.Caught改为Being caught 12.punishing 改为 punished

13.why 改为 that 14.that 改为 which 15.in改为to

第三篇：高中人教版生物选修3前两章课后题答案

专题1 基因工程 1.1 DNA重组技术的基本工具

一、思考与探究

1.限制酶在DNA的任何部位都能将DNA切开吗？以下是四种不同限制酶切割形成的DNA片段：

(1)„CTGCA(2)„AC(3)GC„（4）„G(5)G„(6)„GC(7)GT„(8)AATTC„

„G „TG CG„ „CTTAA ACGTC„ „CG CA„ G„ 你是否能用DNA连接酶将它们连接起来？ 答：

2和7能连接形成„ACGT„ 4和8能连接形成„GAATTC„ „TGCA„； „CTTAAG„； 3和6能连接形成„GCGC„ 1和5能连接形成„CTGCAG„

„CGCG„； „GACGTC„

2.联系你已有的知识，想一想，为什么细菌中限制酶不剪切细菌本身的DNA？

提示：迄今为止，基因工程中使用的限制酶绝大部分都是从细菌或霉菌中提取出来的，它们各自可以识别和切断DNA上特定的碱基序列。细菌中限制酶之所以不切断自身DNA，是因为微生物在长期的进化过程中形成了一套完善的防御机制，对于外源入侵的DNA可以降解掉。生物在长期演化过程中，含有某种限制酶的细胞，其DNA分子中或者不具备这种限制酶的识别切割序列，或者通过甲基化酶将甲基转移到所识别序列的碱基上，使限制酶不能将其切开。这样，尽管细菌中含有某种限制酶也不会使自身的DNA被切断，并且可以防止外源DNA的入侵（本题不要求学生回答的完全，教师可参考教师用书中的提示，根据学生的具体情况，给予指导。上述原则也应适用于其他章节中有关问题的回答。3.天然的DNA分子可以直接用做基因工程载体吗？为什么？

提示：基因工程中作为载体使用的DNA分子很多都是质粒（plasmid），即独立于细菌拟核处染色体DNA之外的一种可以自我复制、双链闭环的裸露的DNA分子。是否任何质粒都可以作为基因工程载体使用呢？其实不然，作为基因工程使用的载体必需满足以下条件。（1）载体DNA必需有一个或多个限制酶的切割位点，以便目的基因可以插入到载体上去。这些供目的基因插入的限制酶的切点所处的位置，还必须是在质粒本身需要的基因片段之外，这样才不至于因目的基因的插入而失活。

（2）载体DNA必需具备自我复制的能力，或整合到受体染色体DNA上随染色体DNA的复制而同步复制。

（3）载体DNA必需带有标记基因，以便重组后进行重组子的筛选。

（4）载体DNA必需是安全的，不会对受体细胞有害，或不能进入到除受体细胞外的其他生物细胞中去。

（5）载体DNA分子大小应适合，以便提取和在体外进行操作，太大就不便操作。实际上自然存在的质粒DNA分子并不完全具备上述条件，都要进行人工改造后才能用于基因工程操作。

4.网上查询：DNA连接酶有连接单链DNA的本领吗？

提示：迄今为止，所发现的DNA连接酶都不具有连接单链DNA的能力，至于原因，现在还不清楚，也许将来会发现可以连接单链DNA的酶。

二、寻根问底

1.根据你所掌握的知识，你能分析出限制酶存在于原核生物中的作用是什么吗？ 提示：原核生物容易受到自然界外源DNA的入侵，但是，生物在长期的进化过程中形成了一套完善的防御机制，以防止外来病原物的侵害。限制酶就是细菌的一种防御性工具，当外源DNA侵入时，会利用限制酶将外源DNA切割掉，以保证自身的安全。所以，限制酶在原核生物中主要起到切割外源DNA、使之失效，从而达到保护自身的目的。2.DNA连接酶与DNA聚合酶是一回事吗？为什么？

答：不是一回事。基因工程中所用的连接酶有两种：一种是从大肠杆菌中分离得到的，称之为E·coli连接酶。另一种是从T4噬菌体中分离得到，称为T4连接酶。这两种连接酶催化反应基本相同，都是连接双链DNA的缺口（nick），而不能连接单链DNA。DNA连接酶和DNA聚合酶都是形成磷酸二酯键（在相邻核苷酸的3位碳原子上的羟基与5位碳原子上所连磷酸基团的羟基之间形成），那么，二者的差别主要表现在什么地方呢？

（1）DNA聚合酶只能将单个核苷酸加到已有的核酸片段的3′末端的羟基上，形成磷酸二酯键；而DNA连接酶是在两个DNA片段之间形成磷酸二酯键，不是在单个核苷酸与DNA片段之间形成磷酸二酯键。

（2）DNA聚合酶是以一条DNA链为模板，将单个核苷酸通过磷酸二酯键形成一条与模板链互补的DNA链；而DNA连接酶是将DNA双链上的两个缺口同时连接起来。因此DNA连接酶不需要模板。

此外，二者虽然都是由蛋白质构成的酶，但组成和性质各不相同。

三、模拟制作讨论题 1.你模拟插入的DNA片段能称得上一个基因吗？ 提示：不能。因为一般基因有上千个碱基对。

2.如果你操作失误，碱基不能配对。可能是什么原因造成的？ 提示：可能是剪切位点或连接位点选得不对（也可能是其他原因）。

四、旁栏思考题

想一想，具备什么条件才能充当“分子运输车”？

提示：能自我复制、有一个或多个切割位点、有标记基因位点及对受体细胞无害等。

1.2 基因工程的基本操作程序

一、思考与探究

1.作为基因工程表达载体，只需含有目的基因就可以完成任务吗？为什么？

答：不可以。因为目的基因在表达载体中得到表达并发挥作用，还需要有其他控制元件，如启动子、终止子和标记基因等。必须构建上述元件的主要理由是：

（1）生物之间进行基因交流，只有使用受体生物自身基因的启动子才能比较有利于基因的表达；

（2）通过cDNA文库获得的目的基因没有启动子，只将编码序列导入受体生物中无法转录；（3）目的基因是否导入受体生物中需要有筛选标记；

（4）为了增强目的基因的表达水平，往往还要增加一些其他调控元件，如增强子等；（5）有时需要确定目的基因表达的产物存在于细胞的什么部位，往往要加上可以标识存在部位的基因（或做成目的基因与标识基因的融合基因），如绿色荧光蛋白基因等。2.根据农杆菌可将目的基因导入双子叶植物的机理，你能分析出农杆菌不能将目的基因导入单子叶植物的原因吗？若想将一个抗病基因导入单子叶植物，如小麦，从理论上说，你应该如何做？

提示：农杆菌可分为根瘤农杆菌和发根农杆菌，在植物基因工程中以根瘤农杆菌的Ti质粒介导的遗传转化最多。根瘤农杆菌广泛存在于双子叶植物中。据不完全统计，约有93属643种双子叶植物对根瘤农杆菌敏感。裸子植物对该菌也敏感。当这些植物被该菌侵染后会诱发肿瘤。近年来，也有报道该菌对单子叶植物也有侵染能力。

根瘤农杆菌侵染植物是一个非常复杂的过程。根瘤农杆菌具有趋化性，即植物的受伤组织会产生一些糖类和酚类物质吸引根瘤农杆菌向受伤组织集中。研究证明，主要酚类诱导物为乙酰丁香酮和羧基乙酰丁香酮，这些物质主要在双子叶植物细胞壁中合成，通常不存在于单子叶植物中，这也是单子叶植物不易被根瘤农杆菌侵染的原因。近年来还发现一些中性糖，如L-阿拉伯糖、D-木糖等也有诱导作用。酚类物质和糖类物质既可以作为根瘤农杆菌的趋化物，又可以作为农杆菌中Ti质粒上Vir区（毒性区）基因的诱导物，使Vir区基因活化，导致T-DNA的加工和转移，从而侵染植物细胞。

需要注意的是农杆菌中不同的菌株，侵染能力有差别，在基因工程中需要加以选择使用。利用农杆菌侵染单子叶植物进行遗传转化时，是需要加上述酚类物质的，同时单子叶植物种类不同，农杆菌侵染进行遗传转化的效果也有很大差异。

如果想将一个抗病毒基因转入小麦，也可以用农杆菌，但要注意两点：①要选择合适的农杆菌菌株，因为不是所有的农杆菌菌株都可以侵染单子叶植物；②要加趋化和诱导的物质，一般为乙酰丁香酮等，目的是使农杆菌向植物组织的受伤部位靠拢（趋化性）和激活农杆菌的Vir区（诱导）的基因，使T-DNA转移并插入到染色体DNA上。

3.利用大肠杆菌可以生产出人的胰岛素，联系前面有关细胞器功能的知识，结合基因工程操作程序的基本思路，思考一下，若要生产人的糖蛋白，可以用大肠杆菌吗？

提示：有些蛋白质肽链上有共价结合的糖链，这些糖链是在内质网和高尔基复合体上加工完成的，内质网和高尔基复合体存在于真核细胞中，大肠杆菌不存在这两种细胞器，因此，在大肠杆菌中生产这种糖蛋白是不可能的。

4.β-珠蛋白是动物血红蛋白的重要组成成分。当它的成分异常时，动物有可能患某种疾病，如镰刀形细胞贫血症。假如让你用基因工程的方法，使大肠杆菌生产出鼠的β-珠蛋白，想一想，应如何进行设计？ 提示：基本操作如下：

（1）从小鼠中克隆出β-珠蛋白基因的编码序列（cDNA）。

（2）将cDNA前接上在大肠杆菌中可以适用的启动子，另外加上抗四环素的基因，构建成一个表达载体。

（3）将表达载体导入无四环素抗性的大肠杆菌中，然后在含有四环素的培养基上培养大肠杆菌。如果表达载体未进入大肠杆菌中，大肠杆菌会因不含有抗四环素基因而死掉；如果培养基上长出大肠杆菌菌落，则表明β-珠蛋白基因已进入其中。

（4）培养进入了β-珠蛋白基因的大肠杆菌，收集菌体，破碎后从中提取β-珠蛋白。

二、求异思维

你能推测出由mRNA反转录形成cDNA的过程大致分为哪些步骤吗？ 提示：1970年，特明（H.M.Temin）和巴尔的摩（D.Baltimore）证实了RNA病毒中含有一种能将RNA转录成DNA的酶，这种酶被称为依赖RNA的DNA聚合酶，由于与中心法则中的从DNA到RNA的转录是反向的，所以称为反转录酶（reverse transcriptase）。

反转录酶既可以利用DNA又可以利用RNA作为模板合成与之互补的DNA链。像其他DNA聚合酶一样，反转录酶也以5′→3′方向合成DNA（图1-3）。

图1-3 由mRNA反转录形成cDNA的过程

cDNA合成过程是：第一步，反转录酶以RNA为模板合成一条与RNA互补的DNA单链，形成RNA-DNA杂交分子。第二步，核酸酶H使RNA-DNA杂交分子中的RNA链降解，使之变成单链的DNA。第三步，以单链DNA为模板，在DNA聚合酶的作用下合成另一条互补的DNA链，形成双链DNA分子。

三、寻根问底

1.为什么要构建基因文库？直接从含有目的基因的生物体内提取不行吗？

提示：构建基因文库是获取目的基因的方法之一，并不是惟一的方式。如果所需要的目的基因序列已知，就可以通过PCR方式从含有该基因的生物的DNA中，直接获得，也可以通过反转录，用PCR方式从mRNA中获得，不一定要构建基因文库。但如果所需要的目的基因的序列完全不知，或只知道目的基因序列的一段，或想从一种生物体内获得许多基因，或者想知道这种生物与另一种生物之间有多少基因不同，或者想知道一种生物在个体发育的不同阶段表达的基因有什么不同，或者想得到一种生物的全基因组序列，往往就需要构建基因文库。2.将目的基因直接导入受体细胞不是更简便吗？如果这么做，结果会怎样？

提示：有人采用总DNA注射法进行遗传转化，即将一个生物中的总DNA提取出来，通过注射或花粉管通道法导入受体植物，没有进行表达载体的构建，这种方法针对性差，完全靠运气，也无法确定什么基因导入了受体植物。此法目前争议颇多，严格来讲不算基因工程。

1.3 基因工程的应用

思考与探究

根据所学内容，试概括写出基因工程解决了哪些生活、生产中难以解决的问题。提示：基因工程可以生产人类需要的药物，如胰岛素、干扰素等。我们吃的某些食品如番茄、大豆等也可以是基因工程产品。农业生产中的抗虫棉、抗病毒烟草、抗除草剂大豆等都已进入商品化生产，上述产品有些是常规方法难以生产的或者生产成本过高。

1.4 蛋白质工程的崛起

一、思考与探究

1.蛋白质工程是应怎样的需求而崛起的？

提示：蛋白质工程的崛起主要是工业生产和基础理论研究的需要。而结构生物学对大量蛋白质分子的精确立体结构及其复杂的生物功能的分析结果，为设计改造天然蛋白质提供了蓝图。分子遗传学的以定点突变为中心的基因操作技术为蛋白质工程提供了手段。

在已研究过的几千种酶中，只有极少数可以应用于工业生产，绝大多数酶都不能应用于工业生产，这些酶虽然在自然状态下有活性，但在工业生产中没有活性或活性很低。这是因为工业生产中每一步的反应体系中常常会有酸、碱或有机溶剂存在，反应温度较高，在这种条件下，大多数酶会很快变性失活。提高蛋白质的稳定性是工业生产中一个非常重要的课题。一般来说，提高蛋白质的稳定性包括：延长酶的半衰期，提高酶的热稳定性，延长药用蛋白的保存期，抵御由于重要氨基酸氧化引起的活性丧失等。

下面举一个如何通过蛋白质工程来提高重组β-干扰素专一活性和稳定性的例子。干扰素是一种抗病毒、抗肿瘤的药物。将人的干扰素的cDNA在大肠杆菌中进行表达，产生的干扰素的抗病毒活性为10 U/mg，只相当于天然产品的十分之一，虽然在大肠杆菌中合成的β-干扰素量很多，但多数是以无活性的二聚体形式存在。为什么会这样？如何改变这种状况？研究发现，β-干扰素蛋白质中有3个半胱氨酸（第17位、31位和141位），推测可能是有一个或几个半胱氨酸形成了不正确的二硫键。研究人员将第17位的半胱氨酸，通过基因定点突变改变成丝氨酸，结果使大肠杆菌中生产的β-干扰素的抗病性活性提高到10 U/mg，并且比天然β-干扰素的贮存稳定性高很多。

在基础理论研究方面，蛋白质工程是研究多种蛋白质的结构和功能、蛋白质折叠、蛋白质分子设计等一系列分子生物学基本问题的一种新型的、强有力的手段。通过对蛋白质工程的研究，可以深入地揭示生命现象的本质和生命活动的规律。2.蛋白质工程操作程序的基本思路与基因工程有什么不同？

答：基因工程是遵循中心法则，从DNA→mRNA→蛋白质→折叠产生功能，基本上是生产出自

86然界已有的蛋白质。蛋白质工程是按照以下思路进行的：确定蛋白质的功能→蛋白质应有的高级结构→蛋白质应具备的折叠状态→应有的氨基酸序列→应有的碱基排列，可以创造自然界不存在的蛋白质。

3.你知道酶工程吗？绝大多数酶都是蛋白质，酶工程与蛋白质工程有什么区别？

提示：酶工程就是指将酶所具有的生物催化作用，借助工程学的手段，应用于生产、生活、医疗诊断和环境保护等方面的一门科学技术。概括地说，酶工程是由酶制剂的生产和应用两方面组成的。酶工程的应用主要集中于食品工业、轻工业以及医药工业中。α-淀粉酶、葡萄糖淀粉酶和葡萄糖异构酶这三个酶连续作用于淀粉，就可以代替蔗糖生产出高果糖浆；蛋白酶用于皮革脱毛胶以及洗涤剂工业；固定化酶还可以治疗先天性缺酶病或是器官缺损引起的某些功能的衰竭等。至于我们日常生活中所见到的加酶洗衣粉、嫩肉粉等，就更是酶工程最直接的体现了。通常所说的酶工程是用工程菌生产酶制剂，而没有经过由酶的功能来设计酶的分子结构，然后由酶的分子结构来确定相应基因的碱基序列等步骤。因此，酶工程的重点在于对已存酶的合理充分利用，而蛋白质工程的重点则在于对已存在的蛋白质分子的改造。当然，随着蛋白质工程的发展，其成果也会应用到酶工程中，使酶工程成为蛋白质工程的一部分。

二、正文中讨论题

某多肽链的一段氨基酸序列是：„—丙氨酸—色氨酸—赖氨酸—甲硫氨酸—苯丙氨酸—„ 讨论：（1）怎样得出决定这一段肽链的脱氧核苷酸序列？请把相应的碱基序列写出来。（2）确定目的基因的碱基序列后，怎样才能合成或改造目的基因（DNA）？

答：（1）每种氨基酸都有对应的三联密码子，只要查一下遗传密码子表，就可以将上述氨基酸序列的编码序列查出来。但是由于上述氨基酸序列中有几个氨基酸是由多个三联密码子编码，因此其碱基排列组合起来就比较复杂，至少可以排列出16种，可以让学生根据学过的排列组合知识自己排列一下。首先应该根据三联密码子推出mRNA序列为GCU（或C或A或G）UGGAAA（或G）AUGUUU（或C），再根据碱基互补配对规律推出脱氧核苷酸序列：CGA（或G或T或C）ACCTTT（或C）TACAAA（或G）。

（2）确定目的基因的碱基序列后，就可以根据人类的需要改造它，通过人工合成的方法或从基因库中获取。

三、异想天开

能不能根据人类需要的蛋白质的结构，设计相应的基因，导入合适的细菌中，让细菌生产人类所需要的蛋白质食品呢？ 提示：理论上讲可以，但目前还没有真正成功的例子。一些报道利用细菌生产人类需要的蛋白质往往都是自然界已经存在的蛋白质，并非完全是人工设计出来而自然不存在的蛋白质。主要原因是蛋白质的高级结构非常复杂，人类对蛋白质的高级结构和在生物体内如何行使功能知之甚少，很难设计出一个崭新而又具有生命功能作用的蛋白质，而且一个崭新的蛋白质会带来什么危害也是人们所担心的。

四、旁栏思考题

1.你知道人类蛋白质组计划吗？它与蛋白质工程有什么关系？我国科学家承担了什么任务？

提示：人类蛋白质组计划是继人类基因组计划之后，生命科学乃至自然科学领域一项重大的科学命题。2001年，国际人类蛋白质组组织宣告成立。之后，该组织正式提出启动了两项重大国际合作行动：一项是由中国科学家牵头执行的“人类肝脏蛋白质组计划”；另一项是以美国科学家牵头执行的“人类血浆蛋白质组计划”，由此拉开了人类蛋白质组计划的帷幕。“人类肝脏蛋白质组计划”是国际上第一个人类组织／器官的蛋白质组计划，由我国贺福初院士牵头，这是中国科学家第一次领衔的重大国际科研协作计划，总部设在北京，目前有16个国家和地区的80多个实验室报名参加。它的科学目标是揭示并确认肝脏的蛋白质，为重大肝病预防、诊断、治疗和新药研发的突破提供重要的科学基础。人类蛋白质组计划的深入研究将是对蛋白质工程的有力推动和理论支持。

2.对天然蛋白质进行改造，你认为应该直接对蛋白质分子进行操作，还是通过对基因的操作来实现？

答：毫无疑问应该从对基因的操作来实现对天然蛋白质改造，主要原因如下：

（1）任何一种天然蛋白质都是由基因编码的，改造了基因即对蛋白质进行了改造，而且改造过的蛋白质可以遗传下去。如果对蛋白质直接改造，即使改造成功，被改造过的蛋白质分子还是无法遗传的。

（2）对基因进行改造比对蛋白质直接改造要容易操作，难度要小得多。

专题2 细胞工程 2.1 植物细胞工程 2.1.1植物细胞工程的基本技术

一、思考与探究

1.为什么“番茄—马铃薯”超级杂种植株没有如科学家所想像的那样，地上长番茄、地下结马铃薯？

提示：1978年，梅尔彻斯（Melchers）等人首次获得了马铃薯与番茄的属间体细胞杂种。他们将培育的二倍体马铃薯品系和番茄叶片细胞进行融合，所产生的杂交株被称为“马铃薯番茄”。像大多数杂种一样，杂交株同时具有马铃薯和番茄的形态特征。其中一些植株形成了“类似块茎的生殖根”，但是没有产生可结实的花、果实以及真正意义上的块茎。到目前为止“马铃薯—番茄”一类的体细胞杂交植物还不能产生经济效益，但是其研究价值不可忽视。

至于马铃薯—番茄没有像人们预想的那样地上长番茄、地下结马铃薯，主要原因是：生物基因的表达不是孤立的，它们之间是相互调控、相互影响的，所以马铃薯—番茄杂交植株的细胞中虽然具备两个物种的遗传物质，但这些遗传物质的表达受到相互干扰，不能再像马铃薯或番茄植株中的遗传物质一样有序表达，杂交植株不能地上长番茄、地下结马铃薯就是很自然的了。

2.自然界中有一种含有叶绿体的原生动物──眼虫，说明植物的细胞器同样可以在某些动物细胞中存活，请探讨：动物细胞与植物细胞之间可以实现杂交吗？如果理论上可行，请设计出具体实验方案。

提示：根据眼虫的特点，动物细胞和植物细胞之间在理论上是可以实现杂交的。具体的实验方案可以设计如下：

二、正文中讨论题 【实验 胡萝卜的组织培养】

1.在组织培养实验中，为什么要强调所用器械的灭菌和实验人员的无菌操作？

提示：植物组织培养中用到的培养基含有丰富的营养成分，有利于培养物的生长，然而各种杂菌同样也可以在上面迅速生长，所以植物组织培养过程中污染现象经常发生。培养基一旦被污染，迅速生长的各种杂菌不但会和培养物争夺营养，而且这些杂菌生长的过程中会生成大量对培养物有害的物质，导致培养物迅速死亡。

造成培养基污染的因素有很多，一般包括：外植体带菌、培养瓶和各种器械灭菌不彻底、操作人员操作不规范等。所以在组织培养实验中用到的植物材料和各种器械都要进行彻底地灭菌，实验人员操作一定要规范，避免带入杂菌。

2.在本实验中，切取胡萝卜块根时强调要切取含有形成层部分，原因是这部分容易诱导形成愈伤组织。请思考一下，胡萝卜的其他部分（如茎、叶、花），是否也能培养成小植株，你能用实验的方法进行验证吗？

提示：胡萝卜的其他部分（如茎、叶、花）也能培养再生形成小植株，只是诱导愈伤组织比较困难。可以让学生参考利用胡萝卜根进行组织培养的实验，尝试设计出利用胡萝卜的茎、叶、花进行组织培养的实验流程。

3.请根据上面的实验过程，概括出植物组织培养技术的流程简图。提示：

2.1.2植物细胞工程的实际应用

一、思考与探究

1.通过查阅资料，请你再列举出植物组织培养技术在我们生活中的另外一些应用。提示：a.拯救濒危植物； b.提供食品制作的原料； c.利用愈伤组织进行转基因操作。

2.请查阅植物人工种子制备技术的详细过程，设计出制备技术的主要流程图。提示：诱导植物愈伤组织→体细胞胚的诱导→体细胞胚的成熟→体细胞胚的机械化包裹

→贮藏或种植

3.请查阅相关文献，设计出一种植物花药组织培养和染色体加倍的实验流程。提示：

二、正文中讨论题

1.人们利用植物的微型繁殖技术来进行工厂化育苗生产，这是利用了该项技术的哪些特点？

提示：植物“微型”繁殖技术具有高效性和可以保持种苗的优良遗传特性的优势。工厂化大规模育苗生产正是利用了植物“微型”繁殖技术的这两方面优势。利用植物“微型”繁殖技术我们可以在短时间中获得大量的优质种苗。

2.人工种子之所以神奇，是由于它具有天然种子不可比拟的特点，想一想它们具有哪些优点？

提示：人工种子的优点：

（1）天然种子由于在遗传上具有因减数分裂引起的重组现象，因而会造成某些遗传性状的改变；天然种子在生产上受季节限制，一般每年只繁殖1～2次，有些甚至十几年才繁殖一次。而人工种子则可以完全保持优良品种的遗传特性，生产上也不受季节的限制。（2）试管苗的大量贮藏和运输也是相当困难的。人工种子则克服了这些缺点，人工种子外层是起保护作用的薄膜，类似天然种子的种皮，因此，可以很方便地贮藏和运输。3.人工种皮是保证包裹在其中的胚状体顺利生长成小植株的关键部分，请探讨人工种皮中应该具有的有效成分是什么？为了促进胚状体的生长发育，我们还可以向人工种皮中加入哪些物质？

提示：针对植物种类和土壤等条件，在人工种子的包裹剂中还可以加入适量的养分、无机盐、有机碳源以及农药、抗生素、有益菌等。为了促进胚状体的生长发育，还可以向人工种皮中加入一些植物生长调节剂。

4.高效抗癌的药物紫杉醇，虽然能造福人类，但却为濒危的红豆杉带来一场灭顶之灾。以“我们能否利用植物组织培养技术大量生产紫杉醇，从而拯救红豆杉”为题，与同学展开讨论，说出植物组织培养技术在节约资源、保护环境方面的重要意义。

提示：可以利用植物组织培养技术来大量生产紫杉醇。现在国内外的科学家们正在研究利用植物细胞培养技术来大量培育红豆杉细胞，希望利用这种方法来大量生产紫杉醇。国内外许多实验室开展了用组织培养法生产紫杉醇的研究，红豆杉属的11种植物现都在进行组织培养。ESC Agenetics公司宣布他们用细胞培养法所得紫杉醇的含量是树皮的2～5倍。国内外在分化细胞株系和培养条件方面做了不少工作，摸索了外植体、光照、培养基组成等因素对细胞培养及紫杉醇生成的影响。现在工艺条件已基本摸清，正研究反应的放大技术等，有望实现通过细胞培养进行工业化生产紫杉醇的目标。

2.2 动物细胞工程

2.2.1动物细胞培养和核移植技术

一、思考与探究

1.幼龄与老龄动物的组织细胞比较，分化程度低的与分化程度高的组织细胞比较，哪一种更易于培养？思考一下，这是什么道理？

提示：细胞的衰老与动物机体的衰老有着密切的关系，细胞的增殖能力与供体的年龄有关，幼龄动物细胞增殖能力强，有丝分裂旺盛，老龄动物则相反。所以，一般来说幼年动物的组织细胞比老年动物的组织细胞易于培养。同样，组织细胞的分化程度越低，则增殖能力越强，所以更容易培养。

2.动物细胞培养要经过脱分化的过程吗？为什么？

提示：脱分化又称去分化，是指分化细胞失去特有的结构和功能变为具有未分化细胞特性的过程。植物的任何一部分，甚至单个细胞都具有长成完整植株的能力。但要发育成完整植株，必须先脱分化，脱分化的细胞具有发育成任何组织的能力，然后进行再分化，形成完整植株。植物细胞培养主要用于农林生产中的作物、苗木育种，快速繁育种苗、培育无病毒植株等，这就要求植物的组织或细胞先进行脱分化。动物细胞的培养有各种用途，一般而言，动物细胞培养不需经过脱分化过程。因高度分化的动物细胞发育潜能变窄，失去了发育成完整个体的能力，所以，动物细胞也就没有类似植物组织或细胞培养时的脱分化过程了。要想使培养的动物细胞定向分化，通常采用定向诱导动物干细胞，使其分化成所需要的组织或器官。3.1997年，美国威斯康星州的一个奶牛场有一头名叫卢辛达（Lucinda）的奶牛，年产奶量为30.8 t，创造了世界奶牛产奶量最高新纪录。目前世界各国高产奶牛场奶牛，年平均产奶量一般为十几吨，而我国奶牛产奶量年平均水平仅为3～4 t。（1）能利用体细胞核移植技术克隆高产奶牛卢辛达吗？请说明理由。

提示：可以用体细胞核移植技术克隆高产奶牛卢辛达。卢辛达的产奶量很高，说明它有高产奶的遗传基础，利用卢辛达的体细胞克隆的奶牛其遗传物质基本上全部来自该奶牛，其克隆牛具有高产的遗传基础，如果精心培育和饲养，有可能在世界范围内推广，克隆牛再与高产的公牛自然繁殖，可得到很多高产的后代，从而加快奶牛改良进程。

但同时需注意，该克隆牛不能无限制地推广，其数量不宜过多，尤其是在小范围内不能无限的繁殖，以避免奶牛群出现近亲繁殖而引起种质衰退。

（2）如果将克隆高产奶牛卢辛达的任务交给你，你将如何对它进行克隆？

提示：首先从卢辛达耳朵（也可用别的组织、器官，耳朵在活体上容易取）上剪取一小块组织，在体外培养获得该组织（如软骨组织）的细胞。从屠宰场取废弃的牛卵巢，抽取卵母细胞体外培养成熟。用显微针去除卵母细胞的核，再将耳细胞注入卵母细胞，用电刺激方法使卵母细胞与体细胞融合，这时供体核就进入了受体卵母细胞，再用电刺激或化学物质激活注入了体细胞核的卵母细胞，使其完成减数分裂和发育过程。核移植胚胎在体外短时间培养后，挑选正常卵裂的胚胎植入经同期发情处理的受体母牛体内。

4.体细胞核移植技术在研究和应用上还存在什么问题？请你查阅资料，了解这方面的前沿动态。

提示：在研究方面，克隆动物基因组重新编程的机制尚不清楚，克隆技术效率低，克隆动物畸形率高、死亡率高、易出现早衰等问题。这些问题尚在研究中。在应用上，生产克隆动物费用昂贵，距大规模应用还有一定距离。

二、正文中讨论题 【讨论1】

多细胞动物和人体的细胞都生活在内环境中，根据你所学的内环境的知识，思考并讨论以下问题：

1.体外培养细胞时需要提供哪些物质？

提示：充足的营养供给、适宜的温度、适宜的pH和气体环境。2.体外培养的细胞需要什么样的环境条件？ 提示：无菌、无毒的环境。【讨论2】

1.在体细胞的细胞核移植到受体卵母细胞之前，为什么必须先去掉受体卵母细胞的核？ 提示：为使核移植的胚胎或动物的遗传物质全部来自有重要利用价值的动物提供的体细胞，在供体细胞的细胞核移至受体细胞之前，必须将受体细胞的遗传物质去掉或将其破坏。2.用于核移植的供体细胞一般都选用传代10代以内的细胞，想一想，这是为什么？ 提示：培养的动物细胞一般当传代至10～50代左右时，部分细胞核型可能会发生变化，其细胞遗传物质可能会发生突变，而10代以内的细胞一般能保持正常的二倍体核型。因此，在体细胞核移植中，为了保证供体细胞正常的遗传基础，通常采用传代10代以内的细胞。3.你认为用上述体细胞核移植方法生产的克隆动物，是对体细胞供体动物进行了100%的复制吗？为什么？

提示：克隆动物绝大部分DNA来自于供体细胞核，但其核外还有少量的DNA，即线粒体中的DNA是来自于受体卵母细胞。所以，用教材中所述的方法克隆的动物不是供核动物完全相同的复制。

此外，即便动物的遗传基础完全相同，但动物的一些行为、习性的形成与所处环境有很大关系，核供体动物生活的环境与克隆动物所生活的环境不会完全相同，其形成的行为、习性也不可能和核供体动物完全相同，从这一角度看，克隆动物不会是核供体动物100%的复制。

三、寻根问底

胰蛋白酶真的不会把细胞消化掉吗？为什么？

提示：胰蛋白酶除了可以消化细胞间的蛋白外，长时间的作用也会消化细胞膜蛋白，对细胞有损伤作用，因此必须控制好胰蛋白酶的消化时间。

四、旁栏思考题

1.进行动物细胞传代培养时用胰蛋白酶分散细胞，说明细胞间的物质主要是什么成分？用胃蛋白酶行吗？

提示：用胰蛋白酶分散细胞，说明细胞间的物质主要是蛋白质。胃蛋白酶作用的适宜pH约为2，当pH大于6时，胃蛋白酶就会失去活性。胰蛋白酶作用的适宜环境pH为7.2～8.4。多数动物细胞培养的适宜pH为7.2～7.4，胃蛋白酶在此环境中没有活性，而胰蛋白酶在此环境中活性较高，因此胰蛋白酶适宜用于细胞培养时的消化。2.为什么对动物细胞进行培养时通常要添加血清？ 提示：血清中含有蛋白质、氨基酸、葡萄糖、激素等，其中蛋白质主要为白蛋白和球蛋白。氨基酸有多种，是细胞合成蛋白质的基本成分，其中有些氨基酸动物细胞本身不能合成（称为必需氨基酸），必须由培养液提供。血清激素有胰岛素、生长激素等及多种生长因子（如表皮生长因子、成纤维细胞生长因子、类胰岛素生长因子等）；血清还含有多种未知的促细胞生长因子、促贴附因子及其他活性物质，能促进细胞的生长、增殖和贴附。因此，细胞培养时，要保证细胞能够顺利生长和增殖，一般需添加10%～20%的血清。

2.2.2动物细胞融合与单克隆抗体

思考与探究

1.植物体细胞杂交技术与动物细胞融合技术有什么不同？

提示：植物体细胞杂交技术与动物细胞融合技术基本相同，不同的是植物体细胞融合前需去掉细胞壁，然后再融合；动物细胞融合是两个体细胞直接融合。

2.制备单克隆抗体时，为什么要选用B淋巴细胞和骨髓瘤细胞融合形成杂交瘤细胞？ 提示：哺乳动物感染抗原后，其体内会形成相应的B淋巴细胞，B淋巴细胞能分泌相应的抗体凝聚或杀死这些抗原。动物在免疫反应的过程中，每一种B淋巴细胞能分泌一种特异性抗体，要想获得大量的特异性抗体，必须使能分泌该单一抗体的B淋巴细胞大量增殖。B淋巴细胞具有产生单一抗体的能力，但不能在体外增殖；骨髓瘤细胞是一种癌细胞，它能在体外培养条件下无限增殖，但不能产生抗体。因此，把一种B淋巴细胞与骨髓瘤细胞进行细胞融合，产生杂交瘤细胞，它会兼有两个亲本细胞的特性──在体外培养条件下能不断增殖，同时能产生出某种特异性的抗体。

第四篇：英语课后翻译题

Unit 1 1.当今的大学生，尽管他们努力地想使自己成才，但对未来还是很模糊的。（establish oneself）

Today's university students are struggling to establish themselves, but they still have ambiguous feelings about their future.2.一个人如果不能找到自我以外的中心，就不能实现他的自我价值。所以，理想的本科教育必须使学生超越自我。(transcend)A man cannot realize his values without finding a center beyond him.So the idealistic of the undergraduate experience must help the student transcend himself.3.我们强烈地希望在大学所学到的知识在今后的工作与学习中能起到重要的作用。（reveal oneself）We eagerly hope that the lessons leaned in the university will reveal themselves in our performance in the workplace and further education.4.四年的本科学习是走向成功生活的唯一道路，这种说法是无法接受的。（go unchallenged）It cannot go unchallenged to say that the 4-year undergraduate experience is the only path to success in life.5.在对一个关键的问题做结论时，如果只相信所谓的专家而不相信自己，不根据调查的结果，不根据实验的数据，那是在冒险。（run the risk of;blind faith in）

We run the risk of making critical decisions, not on the basis of what we know, the findings of investigations, and the data of experiments, but on the basis of blind faith in professed experts.6.我们的事业需要一批受过良好教育又能关心他人的年轻人，他们能团结一致，相互学习，积极参加四化建设。（band together;participate in）

Our task needs a large group of well-informed, caring young people who can band together, learn from each other, and actively participate in the four modernizations.7.如果这所新学校要有生命力的话，它培养的学生不仅要有扎实的基础和熟悉的专业技能，还要有奉献精神。（be to endure;commit oneself）

If it is to endure, the new school should help the students not only acquire a solid basic education and become competent in a specific field, but also be ready to commit themselves to others.8.如果大学生对考试过于投入，就有可能把能力与风险放到次要的地位，这样说一点也不过分。（push to the fringes）

It is not too much to say that if undergraduates excessively devote themselves to examinations, they will push competence and commitment to the fringes.9.我甚至没有跟他说话，当然更不用说与他讨论有关你们学校的改建问题。（much less）I didn't even speak to him, much less discuss the reconstruction of your school with him.10.有人认为考试是很重要的，但也有人认为考试有不少弊端。所以考试留下了一个未能解决的问题——考试对教育有什么影响？（open question）

Some people think examinations are second to none, but some think examinations have a lot of disadvantages.Examinations leave us an open essential question---what influence do examinations exert on education?

Unit 2 1.他不但是位出色的银行家和公认的贸易专家，而且还是位经验丰富的企业主管。(not to mention)He is an experienced banker and an acknowledged trade expert, not to mention an excellent managing director.2.意大利一个和平组织的志愿者不顾危险，已开赴伊拉克首都巴格达，组成“人体盾牌”，以阻止美国轰炸该地。（regardless of）

Regardless of danger, volunteers from an Italian organization for peace have gone to Baghdad, the capital of Iraq, to form a “body shield” for the purpose of preventing the U.S.from bombing the place.3.在这个家庭里，没有人比朱蒂更能致力于经营房地产生意。（be dedicated to）Nobody in the family is more dedicated to operating the real estate business than Judy.4.由于经济不景气，房地产经纪人正处于或降低房价或减少销售量的两难境地。(dilemma)Because of the economic depression, real estate agents are in the dilemma of whether to lower prices or let sales fall off.5.史密斯先生往往靠慎重投资而获取巨额利润。(more ofen than not)More often than not, Mr.Smith earns great profits by careful investment of his capital.6.约翰在学校里各门功课的成绩都不怎么样，但在体育方面倒是身手非凡。(excel at)John did not make much of a mark in his studies at school, but he excelled at sports.7.有条不紊的职责交接是家庭企业长期繁荣的一个条件。(transition;longrange)Orderly transition of responsibilities is a condition for the long-range prosperity of a family business.8.在制定投资计划之前，你最好对投资前景有个清楚地了解。(have a clear picture of)You had better have a clear picture of prospects before formulating a plan for investment.9.尽管雕塑费时，但是仍有一些人以雕塑为职业。(timeconsuming)Although sculpture is a time-consuming art, there are still some people following it as a profession.10.这家电脑软件公司正处于从独资经营到合资经营的转化过程中。(in the midst of)The software company is in the midst of being transformed from an individual proprietorship to a joint venture.Unit 3

1.汽车诞生后发展很快，不就就替代了马。(displace)The automobile was improved very rapidly after it was invented and soon displaced horses.2.由于汽车污染环境并严重伤害人体，甚至杀人，我们可能不得不削减私人拥有汽车的数量而更多地依赖公共交通系统。(mass transit systems)We may have to cut down on the number of privately owned cars and depend more on mass transit systems because cars pollute and maim or even kill people.3.汽车轮子给我们带来了更好、更为便利的交通时，它也应对诸如空气污染、交通事故、交通拥挤之类的许多问题负责。(be guilty of)While wheels(automobiles)have brought with them better or more convenient transportation, they are guilty of many sins, such as air pollution, traffic accidents and traffic congestion.4.美国人对汽车的热爱以及他们较大的工作流动性是出了名的。(be noted for)Americans are noted for their love for cars and great job mobility.5.要是燃料质量和效率的提高和技术的进步能大大减少汽车的排放量，那该多好啊。(if only)If only advances in fuel quality and efficiency and in technology would radically reduce the emissions from automobiles.6.在美国，高速发达的公路网使在各地之间来来往往成为可能。(from coast to coast)A highly developed highway network has made possible the easy movement from coast to coast in the United States.7.一想到这条林荫大道的建设速度，参观者都感到很吃惊：这条路不久前还在开挖及铺设排水管。(the very thought of;tear up)The very thought of the speed at which the beautiful avenue was constructed electrified every visitor;the road had only recently been torn up to lay drain-pipes not long ago.8.环境保护主义者严厉谴责了汽车，认为汽车是产生空气污染的主要因素。(denounce)Environmentalists have denounced automobiles, believing they are a major factor in the production of dirty air.9.由于有便利的公共交通，在大都市的市郊，许多新建的住宅群拔地而起。(rise up,complex)Many new residential complexes have risen up in the suburbs of metropolitan cities because of the availability of convenient public transportation.10.尽管非常喜欢汽车，许多人还是相信广泛的使用公共交通系统能缓解交通拥挤。（lend credence to）

Despite their love for cars, many people lend credence to the extensive use of the public transport system, which can cut down on traffic congestion.Unit 4 1.一些职业观察家认为，现在的年轻人不再对政治和事业感兴趣，他们越来越关注与他们自身关系更为密切的问题。(preoccupied with)Some professional observers believe that young people today are no longer interested in politics and causes, but rather, have become increasingly preoccupied with issues closer to themselves.2.一个妇女所获得的教育程度越高，就越有可能走出小家庭这个环境，到社会上去实现自我。（be likely to,realize oneself）

The higher a woman’s educational attainment, the more likely she is to go out of the private setting of the nuclear family and to realize herself in the community.3.就我而言，一些已婚夫妇做出选择不要小孩的真正原因是他们非常自恋，以至于他们没有多余的爱给别人。(start a family,lie behind,have no margin of,spare)As far as I am concerned, what really lies behind the decision of some married couples not to start a family is that they are so narcissistic and have no margin of love to spare others.4.这家公司甚至在未征求发明人同意的情况下，就将其一项注册过的新发明投放市场。这一行为违反了专利法。(go against)The company put on the market a registered invention even without asking the inventor’s permission, which goes against the patent law.5.在一些国家的敦促下，联合国对该国施加压力，迫使其放弃研制和使用核武器。（pressure sb to do）Urged by some other countries, the United Nations has pressured the country to give up developing and using nuclear weapons.6.按照每个会员必须是无子女的这一规定，怀特先生及其太太只好退出Non-Parent协会，因为他们很快就要当父母了。(alternative,parenthood)According to the rule that every member should remain childless, Mr.And Ms.white have no alternative but to withdraw from the Non-Parent Association, for they will attain parenthood soon.7.他期望通过上演一部肥皂剧来揭示现实生活所固有的复杂性。(implicit)He expects to reveal, by presenting a soap opera, the complexity implicit in real life.8.几乎在每个国家，嗜用麻醉品，酗酒和摧残儿童都有变为最令人深思的社会问题的趋势。(loom as)In virtually every country, drug abuse, alcohol abuse and child abuse loom as most challenging social problems.9.在接受来访时，这些老年人合理地解释了为什么会对当今青年人产生矛盾心理的原因。(be ambivalent about,rationalize)When interviewed, these elderly people rationalized why they were ambivalent about today’s young people.10.不少大学生更关心怎样在毕业后谋得一份报酬优厚工作，怎样在这个充满竞争的社会里迅速得到提升。(be concerned with)Many college students are far more concerned with how to get a highly-paid job on graduation and how to receive a quick promotion in the competitive society.Unit 5

1.总的来说，人变得越来越有同情心；不少家庭收养了来自市孤儿院的孤儿。(take in,orphanage)Generally, people have become more compassionate and quite a few families have taken in an orphan from the municipal orphanage.2.一个有工作的妇女既要照顾她的孩子和和老人，又要设法保有这份工作，是一件非常困难的事情。(hold down)It is a demanding task for a workingwoman to look after her parents and her children while holding down a job.3.起先，我们对他们初次在异国他乡生活感到担忧，但是结果他们在那个国家生活得相当不错。(work out)At first we were worried about their first stay in a foreign country, but things there worked out much better for them.4.今天，中年人的孩子比他们父母的孩子要少得多；40年后人口老化问题可能成为他们孩子的沉重负担。(weigh on)Today's middle-aged people have fewer children than their parents did, and the aging population problem may weigh on them in about 40 years.5.希望目前的教育改革能为学生更好地迎接社会的挑战做好准备。(set up)It is hoped that the current reform in education will better set students up to meet the challenges from society.6.政府想把一部分健康护理的负担转嫁给个人；但是家庭成员并不总是有空的，因为他们不能离开工作来照顾生病的老人。(break away from)The government intends to transfer some of the health-care burden to the individual family;but family members are not always available for the task because they cannot break away from their jobs to look after the sick elderly.7.对养老院床位的需求越来越大，我们不得不想尽一切办法腾出床位。(free up)There is an increasing demand for beds in the nursing home, and we have to try every possible means to free them up.8.随着该国老年人的日益增多，为医疗保健和养老金提供资金可能使政府感到恐惧。(scare the devil out of)With the increase of elderly population in this country, financing health care and pensions could scare the devil out of the government.9.这对年轻夫妇不得不做出牺牲，以避免使他们年迈的慈父伤心。（let down）The young couple has to make some sacrifice to avoid letting their old beloved father down.10.他们在照顾年迈多病的老父时所经历的一切使他们更具有同情心并向养老院捐了款。(go through)What they had gone through in looking after their sick old father made them more compassionate, and they made a donation to the nursing home

第五篇：英语课后题翻译

第一单元

1.这种植物只有在培育它的土壤中才能很好地成长。(other than)

The plant does not grow well in soils other than the one in which it has been developed.2.研究结果表明，无论我们白天做了什么事情，晚上都会做大约两个小时的梦。(may have done)

Research findings show that we spend about two hours dreaming every night, no matter what we may have done during the day.3.有些人往往责怪别人没有尽最大努力，以此来为自己的失败辩护。(justify sth.by)Some people tend to justify their failure by blaming others for not trying their best.4.我们忠于我们的承诺：凡是答应做的，我们都会做到。(remain true to)We remain true to our commitment: Whatever we promised to do, we would do it.5.连贝多芬的父亲都不相信自己儿子日后有一天可能成为世界上最伟大的音乐家。爱迪生也同样如此，他的老师觉得他似乎过于迟钝。(discount;be true of)

Even Beethoven's father discounted the possibility that his son would one day become the greatest musician in the world.The same is true of Edison, who seemed to his teacher to be quite dull.6.当局控告他们威胁国家安全。(accuse sb.of sth.)

They were accused by the authorities of threatening the state security.第二单元

1.要是这部喜剧中的人物更幽默些的话，就会吸引更多的观众。(if...had + past participle, would + have + past participle)

If the characters in this comedy had been more humorous, it would have attracted a larger audience.2.她从未对自己的能力失去信心，因此她有可能成为一名成功的演员。(it is a possibility to)She has never lost faith in her own ability, so it is a possibility for her to become a successful actress.3.我从未受过正式培训，我只是边干边学。(go along)

I never had formal training, I just learned as I went along.4.随着产品进入国际市场，他们的品牌知名度越来越高了。(find one's way into)

As their products find their way into the international market, their brand is gaining in popularity.5.她可以编造一个故事，说自己被窃贼打昏，所有的钱都没了，但她怀疑自己是否能让这故事听起来可信。(make up)

She could make up a story by saying she was knocked unconscious by thieves and that all her money was gone, but she doubted whether she could make it sound believable.6.谁都不清楚他是否故意推迟了这次访问，可是这引起了对他更多的批评。(on purpose)No one was certain whether he postponed the visit on purpose, but this brought more criticism of him.第三单元

1.据报道有七八位官员收受贿赂，市长决定亲自出马调查这件事。(be reported to;look into)Seven or eight officials are reported to have taken bribes and the mayor has decided to look into the affair in person.2.这些工人后悔当时接受管理部门的意见重新回去工作。现在他们再次面临失业的危险了。(regret doing sth.;yield to;be faced with)

These workers regret yielding to the management's advice and going back to work.Now they are again faced with the threat of losing their jobs.3.你只需填写一张表格就可取得会员资格，它可以使你在买东西时享受打折的优惠。(fill out)

You only need to fill out a form to get your membership, which entitles you to a discount on goods.4.不知为什么他们的汽车在半路坏掉了，结果他们比原计划晚到了三个小时。(break down)Their car broke down halfway for no reason.As a result they arrived three hours later than they had planned.5.那位官员卷入了一场丑闻，数周后被迫辞职。(get involved in)

The official got involved in a scandal and was forced to resign weeks later.6.这个靠救济过日子的人开始慢慢地建立起自己的市场，生意日渐兴隆。(build up;one step at a time)

The man living on welfare began to build up his own market, one step at a time and his business is thriving.第四单元

1.我父母不是对我的教育投资，而是把钱花在了买新住房上。(rather than)

Rather than invest in my education, my parents spent their money on a new house.2.如今，人们用于休闲娱乐的开支是过去的两倍。(twice as...as)

Today, people are spending twice as much on entertainment and relaxation as they did in the past.3.一家公司要成功，它必须跟上市场的发展。(keep pace with)

In order to be successful, a business must keep pace with developments in the marketplace.4.与申请这个职位的其他女孩相比，她流利的英语是个优势。(give an advantage over)Her fluency in English gave her an advantage over other girls for the job.5.对于学生而言，没有任何地方比图书馆更好了，在那里所有的图书都任由他们使用。(at one's disposal)

For students, nowhere is better than the library, where all the books are at their disposal.6.我们要充分利用好这个平台，加强交流，拓展合作领域，共谋发展大计。(make use of)We should make full use of the platform to strengthen communication, expand cooperation in more areas and seek further development through joint efforts.第五单元

1.这位小个子男子并不如他看上去那么单纯。(not so...as)

This little man is not so innocent as he appears.2.对这个问题我已束手无策了，所以你不妨去求助于王教授吧。(might as well)

There's nothing I can do about the problem, so you might as well turn to Professor Wang for help.3.双方高度评价了在不同领域合作取得的成果，并希望合作进一步加深。(speak highly of)Both sides speak highly of the fruits in their cooperation in different areas, and hope that the cooperation can be furthered.4.一方面，亲民形象能使新政策更易于被民众接受，另一方面，它也能“广直言之路，启进善之门”。(on the one hand, on the other hand)

On the one hand, an image of being close to the people can get a new policy more easily accepted.On the other hand, it will “encourage people to speak their minds and come up with constructive suggestions”.5.他孤独的感觉时起时落，他有时会对自己、对宠物、对电视机唠叨不休。(rise and fall, at length)

His sense of loneliness rose and fell and he sometimes would talk at length to himself and his pets and the television.6.毕竟，金钱不是万能的，最富有的人不一定是最幸福的。(after all)

After all, money is not everything.The richest people are not necessarily the happiest.第六单元

1.假设你发现了你自己的同事受贿，你会不会无动于衷呢？(Use “suppose” as a conjunction.)

Suppose you found out that your colleague takes bribes, would you just ignore it?

2.他如此固执，我们已对他失望了。跟他争论一点意义都没有。(give up on;it is + adjective + to do/that-clause)

We've given up on him because he is so stubborn.It is pointless to argue with him.3.他突然想到了一个加速实验进程的好办法，但组里的成员却对此意见不一。(hit upon;speed up)

He hit upon a good method to speed up the progress of the experiment, but opinions differed among members of the group on it.4.今天我能够使自己的职业与兴趣相符，之前我是做不到的。(square...with)Today I'm able to square my profession with my interest, which I wasn't able to do before.5.要成为一名驾驶员，视觉上分辨红色与绿色的能力是必不可少的。(distinguish between)The ability to visually distinguish between red and green is essential to becoming a driver.6.这个组由七个人组成，他们经常见面，分享彼此的信息。(consist of)

The team consisted of seven people who met on a regular basis to share their information with each other.第七单元

1.这些科学家在创建基因图谱的过程中体会到：合作不仅仅是一种有吸引力的选择，它还是一种责任。(more than)

In the process of creating the genetic map, these scientists realized that cooperation was more than an attractive option;it was a responsibility.2.他们的研究发现简直就是一个奇迹。由于他们的发现，人们对人类基因的历史有了新的了解。(nothing less than;shed light on)

Their research findings were nothing less than a miracle.As a result of their findings, new light has been shed on the history of human genes.3.事实上，只有勤奋加方法得当才能使你在学习上比他人有优势。(in combination with;give an advantage over)

In fact, only hard work in combination with proper methods will give you an advantage over others.4.法官说这种惩罚将起到杀一儆百的作用。(serve as)

The judge said the punishment would serve as a warning to others.5.感染的危险只限于那些与病人有亲密接触的人。(be confined to)

The risk of infection is confined to those who have close contact with the patients.6.从这一分析中我们可以更好地知道发生了什么以及要做些什么。(in a better position to do)From such an analysis we are in a better position to understand what has happened and what to do about it.第八单元

1.只要他守规矩，我倒不在乎他晚上在外呆得这么晚。(mind + V-ing)

I don't mind his staying out so late as long as he behaves himself.2.与其他计划相比，我更喜欢他的计划，因为我觉得没有任何一个计划比他的计划更实际。(no + singular nouns or plural nouns;in that)

I prefer his plan to others in that I think no plan is more practical than his.3.他们与那家公司中断了生意来往，因为那家公司上一个财政损失惨重，已经破产了。(break off)

They broke off business relations with that company as it suffered huge losses in the last fiscal year and went bankrupt.4.既然你不喜欢他，当初为什么还要邀请他参加你的生日晚会呢？(now that;in the first place)

Now that you don't like him, why did you invite him to your birthday party in the first place?

5.虽然知道获胜的可能性不大，但比赛失败后，我们多少还是有点沮丧。(more or less)Though we knew our chances to win were slim, we were more or less depressed when we lost in the game.6.也许这是为进步而付出的代价，谁知道呢?(pay the price)

Perhaps this was the price that has to be paid for progress—who knows?

第九单元

1.尽管他们做出了巨大的努力，但目前为止，博物馆每天的参观者仍然还是很少。(for all;so far)

For all their great efforts, the museum's daily attendance has so far still been very low.2.作为对政府检查员批评的回应，公司改变了一些做法，而不是放弃自己的规定。(in response to;rather than)

In response to criticism by government inspectors, the company changed some of its practices rather than gave up its rules.3.警方提醒乘客，不要将钱和贵重物品放在提包里，以防被盗。(warn against)

The police warned the passengers against putting money and precious things in bags lest they should be stolen.4.调查应集中于父母和孩子们如何看待学校满足他们需求的那些办法。(focus on)

Surveys ought to focus on how parents and children perceive the ways in which the school satisfies their needs.5.一瞬间，特斯（Tess）由一个天真的女孩变成了一个成熟、受过良好教育的女子。(in a flash)

In a flash, Tess changed from an innocent girl to a mature and well-educated woman.6.我能证实200列新火车正在制造中，第一批将在今年五月投入运营。(come into service)I can confirm that 200 new trains are being manufactured and that the first of those trains will come into service in May this year.第十单元

1.无论你的智商有多高，你的看法都受到个人经历的局限，因此要学会吸纳他人有用的观点。(no matter...)

No matter how high your IQ is, your view is limited by the experience you have had and so you should learn to incorporate the useful perspectives of others.2.这个游戏非常有趣，他们谁也没有注意到时间的流逝。(Use inverted order of “so...that...”;take note of)

So interesting was the game that none of them took note of the passage of time.3.我一直在整理这些旧文件，看看哪些有用，哪些需要扔掉。(sort through)

I've been sorting through these old documents to see which are useful and which can be thrown away.4.随着年龄越来越大，你应该考虑未来的计划。(reflect on)

As you get older you should reflect on future plans.5.他在演出中的亮相简直是个轰动。(nothing less than)

His appearance in the show was nothing less than a sensation.6.他们每个月都从工资中留出一笔钱，用于孩子将来的教育。(set aside)

Every month they set aside a particular amount of money from their salary for the sake of their kid's education in the future.