[专业英语考试复习资料]专业八级分类模拟198.docx

专业英语考试复习资料专业八级分类模拟198专业英语考试复习资料专业八级分类模拟198专业八级分类模拟198LISTENING COMPREHENSIONSECTION A MINI-LECTUREIn this section you will hear a mini-lecture. You will hear the mini-lecture ONCE ONLY. While listening to the mini-lecture, please complete the gap-filling task with NO MORE THAN THREE WORDS for each gap. Make sure the word(s) you fill in is (are) both grammatically and semantically acceptable. You may use the blank sheet for note-taking. You have THIR TY seconds to preview the gap-filling task. Now listen to the mini-lecture. When it is over, you will be given THREE minutes to check your work. The Cloning Technology . The difference between a 1 colony and cloning a mammal A. Clarify the illusion: scientists have been cloning genes for years. B. Definition of clone: a clone is population of cells produced by 2 ; all the cells in a clone have exactly the 3 , using a process known as "recombinant 4 technology". C. Clone a mammal: "nuclear transfer". . Genes, chromosomes and the genome A. Genes - DNAits 5 makes it divide easily. - 6 of chemical groups within DNA form genes. - Genes determine what 7 a given cell will have. B. Chromosomes: genes are linked together to form chromosomes. C. Genome: the entire collection of chromosomes in each cell. D. 8 genes enables scientists to mass-produce proteins that can be used to 9 . . The process of cloning a gene A. Remove DNA from the cell. B. DNA is cut into pieces using 10 . C. To replicate DNA, attach them to non-mammalian DNA. D. Plasmids are easily incorporated into 11 and multiply by themselves. E. The plasmid carries the gene into a 12 cell. F. The gene 13 a plasmid and some proteins. G. The plasmid 14 . H. Copies passed to the cells 15 . I. Each cell contains one or more copies of the recombinant DNA molecule. The gene is now considered cloned. (如需获取本MP3听力录音请搜索标题名) 1.答案:single cell听力原文 The Cloning Technology Today, we are going to talk about the cloning technique. First, we will see the difference between a single cell colony and cloning a mammal. Then we will focus on cell cloning process and its scientific use. In March 1997, the world said "hello" to Dolly, the first mammal to be cloned from an adult cell. We asked ourselves: Would the world soon be populated with human clones? Did you know that cloning isnt new? In fact, scientists have been cloning genes for many years in laboratories around the world. Of course, cloning a genes and cloning a whole mammal are quite different in terms of process and product. But just how do you get from a single cell to a clone? We generally think of cloning as producing a duplicate of something. Scientists, however, usually use the term clone in referring to cells. A clone is population of cells produced by one ancestor. Because of the way cells multiply, all the cells in a clone have exactly the same genetic makeup. Gene cloning uses a process known as "recombinant DNA technology". By contrast, cloning a mammal, such as the sheep Dolly, involves a technology known as "nuclear transfer". Although the end result is the same, the actual processes of gene cloning and mammalian cloning are quite different. But we need to start from the beginning to understand how these complicated and amazing bioengineering technologies evolved. Now, we will study on what genes, chromosomes, and the genome are. Within the body of a mammal, tissues are made of cells. Inside each cell is a long molecule called DNA. Its shape enables it to divide easily. Arrangements of chemical groups within DNA form genes. Genes direct cells to produce proteins, and thus determine what function a given cell will have. For example, skin cells produce proteins which are present in skin tissue, and blood cells produce a protein present in blood. Genes essentially tell each cell what type it is. Genes are linked together to form chromosomes. The entire collection of chromosomes in each of your cells is called genome. All the cells in your body contain the same genome. Once you realize that all cells contain the information for making the whole organism, you know that cloning is theoretically possible. But what makes a skin cell different from a blood cell? The chromosomes within the nucleus of each cell are folded in various ways. Genes that are buried within the chromosomes are inactive, or switched off, while genes on the surface of the chromosomes are active. In a skin cell, the genes for producing skin proteins are active, while in a blood cell, the gene is active. Gene cloning is the process of producing a population of cells all of which contain a specific gene. Using these identical cells, scientists can study the entire genome and obtain clues to how genes are switched on and off. Cloning genes also enables scientists to mass-produce proteins that can be used to treat a variety of diseases. For example, the cells in the pancreas produce a protein called insulin which is important in helping the body maintain appropriate blood sugar levels. Some people have a disease called diabetes because their cells dont produce enough insulin. Cloning the insulin gene has provided a way of producing large amounts of human insulin which is used to treat diabetes. Then, we are going to disclose the mystery of cloning a gene. To clone a gene, scientists remove the DNA from a cell, isolate the specific gene of interest, and then get it to multiply. Sound simple? Not so fast. Lets look at each step. First the DNA must be removed from the cell. Over the years scientists have perfected chemical methods for doing this, based on the physical properties of DNA molecules. The DNA is then cut into pieces using special proteins. You may think of these special proteins as little knives programmed to cut the DNA in specific places. By using the correct special proteins, scientists can isolate whatever gene they want. Once the gene is isolated, it can then be duplicated. Mammalian genes do not reproduce by themselves, however. To replicate them, scientists attach them to pieces of non-mammalian DNA that do replicate on their own. The most common procedure uses small circular pieces of DNA called plasmids that come from bacteria. Plasmids have two useful characteristics. They are easily incorporated into bacteria, they multiply by themselves inside bacteria. The gene of interest is combined with a plasmid and some proteins. The proteins open the plasmid circle and stitch in the new gene. The result is a recombinant DNA molecule. The plasmid carries the gene into a host cell. Once inside the host, the plasmid multiplies, making lots of copies of itself and the gene it contains. When the host cell divides, copies of the recombinant DNA molecule are passed to the cells offspring. As the bacterial cells continue to divide, a colony of identical cells is produced. Each cell contains one or more copies of the recombinant DNA molecule. The gene is now considered cloned. Lets go back now to the example of the insulin gene. Prior to cloning this gene, scientists purified insulin from animal sources, like pigs or cows. Scientists isolated the insulin gene from the DNA of human pancreatic cells. Then they attached the insulin gene to a plasmid and were able to get bacterial cells to incorporate the recombinant DNA. The result was a colony of bacteria that continually produced human insulina little insulin producing factory! 解析 要点题。在讲座的开始部分先说明了讲座的安排。第一个要点就是：First, we will see the difference between a single cell colony and cloning a mammal. 因此答案为single cell。2.答案:one ancestor/the same ancestor解析 细节题。根据讲座中关于克隆定义的内容“A clone is population of cells produced by one ancestor. ”可知答案为one ancestor。3.答案:same genetic makeup解析 细节题。根据讲座原文“Because of the way cells multiply, all the cells in a clone have exactly the same genetic makeup. ”即可得出答案。4.答案:DNA解析 细节题。讲座里出现过“recombinant DNA technology”这个词组。况且DNA是大家比较熟悉的术语，应该不难解答。5.答案:shape解析 细节题。讲座里明确做了解释说：Inside each cell is a long molecule called DNA. Its shape enables it to divide easily. (DNA容易分裂是由它的形状决定的。)所以答案为shape。6.答案:Arrangements解析 推断题。讲座中提到：Arrangements of chemical groups within DNA form genes. (DNA中的化学组织的排列决定了基因。)所以答案为arrangements。7.答案:function解析 细节题。讲座中说道：Genes direct cells to produce proteins, and thus determine what function a given cell will have. (基因指示细胞产生蛋白质，最后决定哪些细胞有哪些作用。)因此答案为function。8.答案:Cloning解析 细节题。讲座中提到：Cloning genes also enables scientists to mass-produce proteins that can be used to treat a variety of disease. 填空用的是动名词形式。9.答案:treat diseases解析 归总题。讲座中相关内容是：Cloning genes also enables scientists to mass-produce proteins that can be used to treat a variety of diseases. 可见克隆技术可以用于治病，因此答案为treat diseases。10.答案:special proteins解析 细节题。根据讲座内容“The DNA is then cut into pieces using special proteins. ”可直接得出答案。11.答案:bacteria解析 细节题。根据讲座原文“They are easily incorporated into bacteria.”可以直接得出答案。这里要注意的是bacteria是bacterium(细菌)的复数。12.答案:host解析 细节题。在讲述基因克隆的过程中，有很多烦琐难懂的步骤，但是讲座里提到：The plasmid carries the gene into a host cell. 因此答案为host。13.答案:is combined with解析 细节题。根据讲座原文“The gene of interest is combined with a plasmid and some proteins. ”即可得出答案。14.答案:multiplies解析 归总题。讲座提到克隆过程中质粒需要繁殖：Once inside the host, the plasmid multiplies, making lots of copies of itself and the gene it contains. 因此答案为multiplies。15.答案:offspring解析 细节题。根据讲座中提到的“copies of the recombinant DNA molecule are passed to the cells offspring”直接拷贝入题即可。SECTION B CONVERSATIONIn this section you will hear ONE conversation. The conversation will be divided into TWO parts. At the end of each part, five questions will be asked about what was said. Both the conversation and the questions will be spoken ONCE ONLY. After each question there will be a ten-second pause. During the pause, you should read the four choices of A, B, C and D, and mark the best answer to each question on ANSWER SHEET TWO. You have THIRTY seconds to preview the questions. (如需获取本MP3听力录音请搜索标题名) 1.A.Husband and wife.B.Professor and student.C.Client and librarian.D.Customer and waitress.答案:C听力原文 L: Good morning, City Central Library. May I help you? M: Yes, I want to order some books please. You can send them to me through the post or courier, cant you? L: Yes, certainly. Let me get the form and take down some details. First, your name please, sir. M: Willy Humpshire. Thats capital H-U-M-P-S-H-I-R-E. L: Willy Humpshire. And your membership number? M: Thats L 9231385. L: L923 . M: 1385. L: Thank you. Now your address please. Thats the address you want us to send the items to. M: Its 15 Lonkon Street, Annandale. L: And could I have your phone number and your fax number please? M: They are the same, 663-6947. L: 663-6947. M: Thats correct. L: Thank you. And may I ask why youll need the books? Im sorry about this, but we have to have this information whenever we send books out from a telephone request. M: No problem. Im preparing an article for the environment watch section of the local newspaper. We are quite concerned about the problems we are facing now, especially since weve been getting so many tourists in the district. L: Oh I see. Im so glad someone is doing something about publicizing the problem. M: Now how long can I keep the books for? L: Well, as you know, our normal loan period is three weeks with a two-week extension over the phone. However, in cases where we send books out by post we allow a longer initial loan period to allow for the delivery time. So you may have the books for six weeks from the date of postage. But Im afraid the two weeks extension wont apply then. However you would be able to renew by bringing them in for stamping, provided no one else has a reservation on them. M: I should think the normal period will be enough. Anyway I have to hand in the article within a month. Now how do you prefer the postage and photocopy fees to be paid? What is the probable relationship between the two speakers? 解析 信息题。询问两位讲话者的关系。从录音开始处的L: Good morning, City Central Library. May I help you? 和M: Yes, I want to order some books please. 即可判断男士打电话去图书馆借阅书籍，接电话的女士是管理员。因此答案是C。2.A.L9231358.B.L9321185.C.L9231385.D.L9213835.答案:C听力原文 Whats the mans membership number? 解析 信息题。管理员问And your membership number?男士回答Thats L 9231385. 所以C是答案。考生如果没有准确记录，选项A、B、D容易成为迷惑答案。3.A.15 Lonkon Street, Annandale.B.50 Lonkon Street, Annandale.C.51 Lonkon Street, Annandale.D.15 London Street, Annandale.答案:A听力原文 What is the address of the man? 解析 信息题。管理员询问男士的地址，男士回答Its 15 Lonkon Street, Annandale. 所以答案是A。此选项容易和选项D混淆。4.A.Description of the district.B.Environmental protection.C.Important reports in Australia.D.Australian government.答案:B听力原文 What is the main content of the mans article? 解析 推理题。四个选项在对话中都出现过，需要根据题意排除干扰项，选择正确的一个。当管理员询问男士借书的目的时，他回答道：Im preparing an article for the environment watch section of the local newspaper. We are quite concerned about the problems we are facing now, especially since weve been getting so many tourists in the district. 可以推断男士为当地报纸的环保专栏写文章，目的是呼吁大家关注当地的环境问题。所以选项B正确。5.A.Three weeks.B.Two weeks.C.Six weeks.D.Four weeks.答案:A听力原文 How long will the man probably keep the books he borrows? 解析 推理题。虽然借阅时间不是难点，但对话中图书管理员介绍了很多种借阅时间供借阅者考虑，无疑增加了答题难度。Well, as you know, our normal loan period is three weeks with a two-week extension over the phone. However, in cases where we send books out by post we allow a longer initial loan period to allow for the delivery time. So you may have the books for six weeks from the date of postage. But Im afraid the two weeks extension wont apply then. However you would be able to renew by bringing them in for stamping, provided no one else has a reservation on them. 这段话表明通常借阅的时间是3周，如果有需要，可以通过电话续借2周。但邮寄图书需要考虑邮寄时间，所以借阅的时间从寄出之日起算为6周，但取消2周的续借期，除非没有别人要求借阅，而且必须亲自到图书馆续借。男士的回答：I should think the normal period will be enough. 表明他只要常规借阅期就可以了。但他是指3周还是加上续借2周的总共5周呢?下一句Anyway I have to hand in the article within a month. 说明他的投稿的文章必须在1个月内完成，不可能借阅5周。因此选项A正确。 (如需获取本MP3听力录音请搜索标题名) 6.A.Credit card.B.Cash.C.Money order.D.Cheque.答案:B听力原文 L: We accept both cash and credit card, but it will be such a small sum. It might be more convenient to send us a money order. M: Hmm. Would it be all right if I left it until I come in next time and just pay cash then? L: Of course. Theres no problem with that at all. M: Fine. Ill do that