B3U8 课文翻译及课后练习答案

1、Unit 8 Nature and NutureIn-class reading课内阅读参考译文基因、环境与双胞胎1 遗传与环境究竟哪一个影响更大呢?在相当大的程度上，一个人生来具有的潜力将决定他一生的作为。因此遗传即命运，是命中注定的东西。然而，基因并不是在真空中发挥作用的；一旦我们开始认识到基因在个人发展中所起的作用，我们就会明白，没有与其相互作用的环境，就不可能有任何个人的发展。没有一个特点是完全由环境或者完全由基因造成的。2 遗传和环境的相对影响在同卵双胞胎中最易观察到。大多数的同卵双胞胎是在一起抚养长大的，因而无论在外表还是行为上都惊人地相像。这些实例证明，若在同样的环境中抚养成长，

2、具有相同基因的个体就会以几乎同样的方式对环境作出反应。但这些例子并不能说明如果把这些同卵双胞胎分开抚养会发生什么情况。3 对分开抚养的同卵双胞胎已进行了许多研究。被研究的这些双胞胎都生活在美国，成长的自然环境几乎相同，并且具有几乎相同的营养史。因而，正如所料，他们在外表、身高和体重上极其相似。也有例外：一对双胞胎中的一个患了相当严重的疾病而另一个却没生病；但是总体而言，同卵双胞胎，甚至从婴儿时就分离的同卵双胞胎，在心理和身体上会如此相似，给每个人留下了深刻的印象。4 在对从一出生就分离的19对双胞胎的研究中，研究者发现，其中约三分之二的双胞胎之间的差异与一起长大的双胞胎之间的差异一样不明显。这

3、有力地说明了基因的影响力和环境作用的局限性。然而，必须记住的是，尽管被研究的同卵双胞胎生活在不同家庭里且相距甚远，但总体而言，那些家庭的环境基本上没有什么差异。通常都会千方百计地将每个孩子安置在和他自己原来的家庭背景相同的家庭里，因而发现这些双胞胎成长中有不少相似之处就不足为奇了。但是在那些分开抚养的双胞胎的生长环境有较大差异的实例中，双胞胎之间的差异就很大。下面的例子说明了在对比度很大的环境中成长的同卵双胞胎的情况。5 格莱迪丝和海伦出生于俄亥俄州的一个小镇，在大约18个月时被分开抚养。她们直到28岁才再次相遇。海伦被领养了两次。她最初的养父母结果靠不住，两年后海伦又被送回到孤儿院。过了几个

4、月，她再一次被住在密歇根东南部的一对农场主夫妇领养。此后25年她一直住在那里。她的第二个养母尽管本身没受过什么教育，却下决心要让海伦得到良好的教育；海伦最终大学毕业，教了12年的书，26岁时结婚，并有了一个女儿。6 格莱迪丝被加拿大的一个列车乘务员及其妻子领养。她读三年级的那一年，全家搬到了加拿大落基山脉一带一个相当偏僻的地方，那儿没有学校，格莱迪丝的正式教育也就此结束，直到全家搬到安大略省后才得以继续。于是格莱迪丝就呆在家里干家务，一直到她17岁，随后在一家针织厂工作。19岁那年她去了底特律，找到一份工作，21岁时结了婚。7 海伦在儿童和成年时期都一直比格莱迪丝健康，但除了这一点以及各自所受

5、的教育不同之外，她们的生活环境十分相似。她们的体重、身高、发色和牙齿都十分相似。她们之间的区别显然与她们各自的家庭生活和社交生活不同有关。8 海伦自信、举止得体、充分利用了她外表的优势，在社交中也显得很从容，有修养。格莱迪丝则害羞、忸怩、沉默寡言，缺乏迷人或优雅的风度。一位研究她们的科学家曾经说过：“这两个双胞胎之间的悬殊差异真可谓是大学教育的颇有说服力的广告。”9 考虑到她们环境方面的经历的本质不同，海伦和格莱迪丝之间的差异也就不足为怪了。由于心理特点在很大程度上取决于经历，可想而知心理特点也反映经历。另一方面，那些不易受环境影响的特点更有可能在同卵双胞胎中表现出高度的相似性。尽管基因十分重

6、要，但是基因本身决不能完全决定任何一个特点。我们的能力会达到什么程度由基因注定，而我们真正做了什么则主要由环境决定。After-class reading课外阅读参考译文科学再次关注双胞胎1 如果你对双胞胎感兴趣的话，那么双胞胎镇会使你着迷。2 从1976年起的每个夏天，这个位于俄亥俄州克里夫兰郊外的小镇都会挤满众多的双胞胎。去年夏天，有2,356对双胞胎从世界各地来到这里，参加并观看游行、焰火、魔术表演、五公里赛跑以及一百多项的比赛：评选出年纪最大的、年纪最小的、最像的、最不像的，以及两人相加笑起来嘴咧得最大的双胞胎。3 你要是去过那儿的话，你可能会注意到有很多科学家也参加了这个盛会。有些科

7、学家是来寻找引起疾病的缘由例如皮肤病、癌症、心脏病。另外一些科学家则对双胞胎自身的感受感兴趣。但是在所有的科学家中，从事最重要的也是最有争议的工作的是这样一些科学家，他们专门研究先天遗传和后天培养这个由来已久的问题，即研究有关我们是如何发展成现在这个样子的。4 为什么我们有些人精通数学或擅长写作，而另外一些人则在艺术或篮球上出类拔萃？是什么造成了我们在智力、才能和品味上的差异？这些主要是由我们从父母那里继承来的基因（先天遗传）决定的吗？同我们的生活经历（后天培养），也就是我们成长的社会环境又有多大关系呢？5 如果你是一个对这个问题感兴趣的科学家，你难道不想研究一下同卵双胞胎吗？想一想：从同一受

8、精卵发育出来了两个人。也就是说，两个人有完全相同的基因。同卵双胞胎之间存在的任何不同都只能是他们成长环境不同的结果。但是你能说他们之间的任何相同点都是基因相同的缘故吗？6 不一定吧。记住，大多数双胞胎都有相似的成长环境同样的房子，同样的饮食，同样的亲戚等等。研究分开在不同环境下抚养的同卵双胞胎，或许是你能准确衡量先天遗传和后天培养所起的作用的唯一办法。7 在过去的10年间，由心理学家小托马斯J布沙尔带领的一组科学家研究了大约65对分开抚养的同卵双胞胎。他们还研究了大约45对分开抚养的异卵双胞胎。8 科学家们把每对双胞胎带到明尼苏达大学进行为期一周、深入细致的检测。小组里的医生和牙医们给这些双胞

9、胎进行了全面的体检。他们记录了双胞胎的身高、体重、眼睛颜色、耳朵的形状和头围。9 同时，心理学家们还对双胞胎进行了智商和性格测试。为了测试性格，心理学家们设法测定了：双胞胎们对事情担忧的程度，他们是谨慎型的还是鲁莽型的，以及他们的创造力如何。他们根据双胞胎们对一些陈述的回答来衡量这些方面以及其他一些性格特征，这些陈述包括“我很少鲁莽行事”,“木柴燃烧的火焰激发我的想象力”等。一周结束时，每个双胞胎都回答了大约15,000个问题。10 布沙尔小组对分开抚养的双胞胎之间的相似之处感到非常吃惊。例如他们的手势和姿势经常很相似，真是令人惊奇。在照片上，很多双胞胎摆出的姿势几乎一模一样。有些同卵双胞胎还

10、发现他们的生活方式极其相似。11 “吉姆兄弟”是布沙尔研究的第一对同卵双胞胎，他们出生四周后就被不同的家庭领养。他们都在俄亥俄州长大，彼此相隔45英里。当他们在39岁重逢时，发现了一系列惊人的相同之处：二个人都叫吉姆，都开同一型号的蓝色雪佛兰，都喜欢做木工，都有啃手指甲的习惯，养的狗都叫“Toy”。两个人都有傍晚头痛的毛病，都是在18岁时开始的。12 在吉姆兄弟之间所发现的相同点在明尼苏达小组研究的双胞胎身上都普遍存在。有些对明尼苏达研究工作持批评态度的人说“这些巧合没什么可奇怪的”。他们认为每个人的生活里都有很多的细节，因此必然会有巧合。而且，对于异地抚养的同卵双胞胎之间发现的任何一个巧合，

11、持怀疑态度者都能指出大量未被发现的不同点。同一对双胞胎可能有不同型号的电视机，支持不同的足球队。但不同点是不会被报道的，因为它们不会使人吃惊。13 但是除了巧合之外，明尼苏达的科学家们收集并分析了有关双胞胎的健康、智力和个性方面的大量数据。布沙尔认为，有关异地抚养的同卵双胞胎的数据清楚地显示了：先天遗传，即我们所继承的基因，对我们的生活有显著的影响。该小组发现，这些同卵双胞胎在身高、指纹和心率等生理特征方面极其相似。成年的同卵双胞胎还往往有相似的病史，例如同时得了青光眼。14 明尼苏达小组报告说智力似乎也更受基因的影响而不是环境。虽然由不同的家庭抚养长大，布沙尔小组研究的同卵双胞胎在成人智力测

12、验中所得的分数完全相同或几乎相同。15 但是最令人吃惊的是，明尼苏达小组发现基因对于个性的形成起着重要作用，例如，会决定我们是否尊重传统、循规蹈矩，还是会成为坚定的离经叛道者。根据布沙尔的看法，你与生俱来的基因对你是否自信、快乐、乐观或者对世界上的事是否持消极态度有很大影响。明尼苏达小组的一位心理学家，南希西格尔说，“这项研究令人信服地表明：基因影响人们行为的每个方面。” 16 另一些科学家不同意这个说法。他们质问，既然光是对智力的定义就多种多样，你们又怎么能够去研究智力是否是遗传的呢？他们认为同样的问题也存在于其他的性格特征中。17 布沙尔本人表示了这样的观点，即使是他所研究过的最相似的双胞

13、胎也是彼此不同的。因此即便基因对我们的生活有很大的影响，它们也不是唯一起影响作用的因素。我们的日常经历也有助于塑造我们。18 你知道这意味着什么：为了考试，你还得学习！课内阅读练习答案 Part One Preparation1. Talking about TwinsSamples1) I knew a set of twins in my class in the middle school. They looked alike and usually dressed alike so we often got them mixed up. They were very close to

14、each other and could exchange their ideas quickly. But they had quite different personalities: one was shy, quiet, and self-conscious while the other was self-confident and optimistic.2) I think its because there arent many twins around us. People are always curious about things that they rarely see

15、. Another reason for their curiosity is probably that twins resemble each other, which is very unusual among other people. 3) They must be proud because they are different from others. They may feel happy because they can enjoy each others company at home. They may feel lonely because it may be more

16、 difficult to make friends with other people. They may feel bored and discouraged because every day they will see the mirror image of themselves. They may often feel jealous of each other since they are competing for their parents love and attention.2. Nature, Nurture or BothSamples1) Nature and nur

17、ture: A person can have natural talents, but mastery always takes some effort. You have to try to succeed.2) Nature: No matter what the hairdo (hair style) is, their hairlines stay the same. This trait is due to the genes that the mother passed on to her son.3) Nature: Theres nothing wrong with Juli

18、es nose. Some people have the genes to smell freesia, others dont.4) Nurture: Are you wild about mysteries, adventures, or biographies? Your tastes may be determined by the books that are available in your home or school. 5) Nurture: Somebodys favorite clothes and color can change as quickly as the

19、cover of a style magazine. You might say its due to the JEANS, not the GENES.6) Nature: Genes determine whether a persons earlobes are attached or detached.7) Nature and nurture: Your personality isnt determined only by genes. There are a lot of other factors that make you who you are, such as where

20、 you live and the people you meet.8) Nature and nurture: Practice makes perfect! Melissa earned her position as a star player because she uses her athletic ability and works so hard.3. An intelligent mother makes an intelligent kid?Samples- Yes, I agree. I can give a lot of evidence to support this

21、view. Take my best friend in high school for example. His mother is very intelligent, excelling all the other students in her class since her primary school days. She graduated from Qinghua University and is now working in a research institute, involved in many high-tech projects, and has won many h

22、onors. Like his mother, my friend is also very intelligent. He was very quick-minded and was always the first one to raise his hand when the teacher asked some tough questions. He was the one I would turn to when I had questions and I was never disappointed. And like his mother, he is now studying i

23、n Qinghua University as well, majoring in electronic engineering. My mother is reasonably intelligent, so am I. And in choosing a girlfriend, my No.1 criterion is INTELLIGENCE!- No, I dont agree with that. Everyone agrees that “g”, which refers to general intelligence, tends to run in families. Lots

24、 of studies have shown it and most people can see it when they look at their own families, friends and acquaintances. Yet, so far no single gene has been conclusively linked to intelligence. Rather it appears to be a case of complex interactions on many levels between many different genes something

25、known as polygenic inheritance. So my view is that, for one thing, the intelligence of both parents would influence the intelligence of a kid, and, for another, the environment that a kid grows up in would also influence the intelligence of the kid. 4. What makes us who we are?1) expected2) conclude

26、3) account4) nurture5) argues6) myth7) predetermine8) react9) consequences10) revolution11) between12) creaturePart Two Reading-Centered ActivitiesIn-Class ReadingI. Pre-ReadingSampleThe conclusion is not justified because the sets of twins studied shared not only the same genes but also the same en

27、vironment. Numerous studies have shown that both nature and nurture play a part in personal development. The similarities between the sets of twins are not due entirely to genes since environment also plays a role.III. Post-ReadingReading Comprehension1. Understanding the Organization of the Text1)

28、Introduction (Para.1) No characteristic is caused exclusively by either environment or genes.2) Research on the relative effects of heredity and environment (Para.2-8).A. Studies on identical twins raised together (Para.2)Findings: They are remarkably alike in both appearance and behavior.Implicatio

29、n: Individuals with the same genes, when raised in the same environment, will respond to it in much the same way.B. Studies on identical twins raised apart in similar environments (Para.34) Findings: They exhibited great psychological and physical likenesses.Implication: This does not inform us of t

30、he power of genes and the limitation of the effect of the environment.C. Studies on identical twins raised apart in contrasting environments (Para.58)Findings of a case study on Gladys and Helen: Their similarities: Their weight, height, hair color, and teeth were very similar.Their differences in p

31、ersonality: Helen was confident, graceful, made the most of her personal appearance, and showed considerable polish and ease in social relationships; while Gladys was shy, self-conscious, quiet and without charming or graceful manners.Implication: Genes alone are never absolutely responsible for any

32、 trait.3) Conclusion (Para.9)What we can do is set by the genes, but what we actually do is largely determined by the environment.2. Understanding Specific Information1) F 2) F 3) F 4) F 5) T 6) T 7) F 8) TVocabulary Practice1. 1) C2) A3) C4) C5) A6) B7) B8) B2. 1) resemble2) alike3) Like4) similar5

33、) same6) Identical, same, alike3. 1) absolutely2) eventually3) obviously4) Similarly5) remarkably6) approximately7) exclusively8) actuallyAfter-Class ReadingPart Three Further Development1. Enriching Your Word Power1) B 2) A 3) A 4) A 5) B 6) B 7) B 8) C 9) B 10) A 11) B 12) C2. What do you know?Ste

34、p One1) C DNA is short for deoxyribonucleic acid (de-oxy-ri-bo-nu-cle-ic acid). DNA is a chemical in every cell of your body. It is shaped like a long, twisted ladder. This shape is called a double helix.2) C DNA is found in all living things, including you! This amazing chemical tells each cell wha

35、t to do and determines what an organism will look like.3) C Scientists are still debating how nature and nurture work together to make you who you are, but most agree that both play a role.4) B Scientists used to think that humans had about 100,000 genes. Recently, it was discovered that we have abo

36、ut 10,000 to 20,000. We carry two copies of every gene, one copy from each parent.5) C Many things, such as what you eat, can affect how tall youll grow. Even if you have talent, making art takes practice. But eye color is a trait passed on through genes.6) B Before Dolly, scientists used different

37、techniques to clone animals. Dolly was the first animal to be cloned from a cell of an adult mammal.7) C Believe it or not, humans and chimps have a lot of DNA in common! But as you can see, even small differences in genetic codes can make big differences in what an organism looks like.8) B You cant

38、 tell by looking at a fruit fly and a human, but they have a lot of similar DNA. In fact, scientists study the fruit fly genes to help advance medical knowledge.9) BThe human genome has a lot of DNA that carries no information and is not active genetically. Its still a mystery to scientists why this

39、 DNA is there and what it does.10) C Although they can have very different personalities, identical twins are often difficult to tell apart physically. But the fingerprints of each are unique.Step TwoSample:What Do You Know about DNA?Every day you hear people talking about DNA, but do you know what

40、is DNA and how it is related to our life? Let me tell you briefly.DNA is the short form of deoxyribonucleic acid. It is a chemical in every cell of our body, in the shape of a double helix. DNA is found in all living things, including you and me! This amazing chemical tells each cell what to do and

41、determines what an organism will look like. Scientists used to think that humans had about 100,000 genes. Recently, it was discovered that we have between 10,000 to 20,000 human protein-coding genes. We carry two copies of every gene, one copy fromeach parent. Living beings depend on genes, as they

42、specify all proteins and functional RNA chains. Genes hold the information to build and maintain an organisms cells and pass genetic traits to offspring. All organisms have many genes corresponding to various biological traits, some of which are immediately visible, such as eye color, or number of l

43、imbs, and some of which are not, such as blood type or increased risk for specific diseases, or the thousands of basic biological processes that comprise life. Genes, to a large extent, decide who we are, what we look like, and what we can do, but, of course, the environment we live in also plays a

44、part.Believe it or not, humans and chimps, the closest living relatives to humans, have a lot of DNA in common (about 98%)! But as you can see, even small differences in genetic codes can make big differences in what an organism looks like. You dont actually act or look like a chimp, right?Presently

45、, only the function of a few percent of the DNA is known, the rest has been believed to be useless garbage, commonly called “Junk DNA” by molecular biologists. There is now increasing evidence indicating that this DNA is not “junk” at all. It has been found to have various regulatory roles, which me

46、ans that this so-called “non-coding DNA” influences the behavior of the genes, the “coding DNA”, in important ways. However, the knowledge is still incomplete about this DNA. And there is little knowledge about the relationship between non-coding DNA and the DNA of genes. I believe scientists will t

47、ell us more with the furthering of their research. For Teachers:Strategies for Giving a speechPart OneThroughout history people have used public speaking as a vital means of communication. Pericles, the Greek leader, said more than 2,500 years ago, “One who forms a judgment on any point but cannot e

48、xplain it clearly might as well never have thought at all on the subject.” The same is true today.The ability to clearly and effectively communicate your thoughts and ideas is important in both your personal and professional life.Personally, it can help you develop deeper and more fulfilling relatio

49、nships of all types.Professionally, it can help you stand out among your colleagues and attain positions of leadership and influence.Following are some basic concepts of a speech:Organization:BeginningObjectivesl Get the attention and interest of your audience;l Reveal the topic of your speech;l Est

50、ablish your credibility (you are qualified to speak on a given topic) and good will;l Preview the body of the speech.Devicesl Relate the topic to your audience;l State the importance of your topic;l Startle the audience with an arresting and intriguing statement;l Arouse the curiosity of the audienc

51、e;l Question the audience;l Begin with a quotation;l Tell a story;BodyMain Pointsl Number of main points: make a few main points stand out and be remembered;l Strategic order of main points: chronological order, spatial order, causal order, problem-solution order, topical order, etc.EndingPurposesl

52、Signal the end of the speech; l Reinforce the central idea.Devicesl Summarize your speech;l End with a quotation;l Make a dramatic statement;l Refer to the introduction;Supporting evidence: ExamplesTypesBrief examples1. A brief example may be used to introduce a topic.2. You can pile them one upon t

53、he other until you create the desired impression.Extended examplesA story, narrative, or anecdote developed at some length to illustrate a point.Hypothetical examplesAn example that describes an imaginary or fictitious situation.Statisticsl Use representative statistics;l Choose statistics from a re

54、liable source;l Use correct statistical measures. TestimonyDefinitionA formal statement about something that you saw, know, or experienced, usually given in a court of law.Types1l Expert testimony;l Peer testimony: first -hand experience on the topic.2l Direct quoting;l Paraphrasing: expressing by u

55、sing different words, especially in order to make it shorter or clearer.Presenting the speech:LanguageUse language accurately and appropriately.DeliveryVoiceVolume, pitch, rate, pauses, vocal variety, articulation, etc. BodyPersonal appearance, movement, gestures and postures, eye contact, etc.Visua

56、l aidsTipse.g. using PowerPoint slidesl Keep visual aids simple;l Make sure visual aids are large enough;l Use a limited number of slides;l Display visual aids only when discussing them;l Talk to your audience, not to your visual aids;l Explain visual aids clearly and concisely.Part TwoFind two samp

57、le speeches, one to inform and the other to persuade, and 1) analyze the scripts together with the students in terms of the organization and the supporting evidence used; 2) watch the speeches to see how the speakers present the speeches.Part ThreeAsk the students to work in groups, with each group preparing a speech, either an informative speech or a persuasive speech. Each group chooses one representative to deliver it to the whole class. Then invite comments from the whole class, using the concepts presented in Step One.3. Relating Your