Using LanguageⅡ教学设计案例

Unit 2 Cloning Teaching goals 教学目标

Integrating skills and writing. 1.Target language 目标语言

a. 重点词汇

debate, issue, competition, in charge, topic, argument, reply to, summarize, profitable, donate, existence, embryo, justified, transfer, ethically. b. 重点句子

I suggest that medical cloning is very important of curing serious illnesses that at present have no cure. I would like to suggest that medical cloning is not as simple as issue as my colleague claims. 2. Ability goals能力目标

Activate the students to show their opinions about the cloning. Enable the students to write an article on this debate. 3. Learning ability goals学能目标

Help the students learn how to organize a debate and how to write a short composition of the debate. Teaching important and difficult points教学重难点

How to organize the debating materials. How to write a short composition of the debate. How to write a report. Teaching methods教学方法

Task-based teaching method. Teaching aids教学准备

A computer and a projector. Teaching procedures & ways教学过程与方式

Step Ⅰ Revision Check the homework and ask the students to speak out their opinion about the

medical cloning. Step Ⅱ Reading task

T: Homework check is over. Please turn to page 58. Today we will make a debate. To begin with, I want to ask you what your opinion about debate is, have you seen any TV debates? S: Yeah, we have seen college students’ debate on TV.

S2: I know in a debate there is one chairperson some-times two, four members each group, two leading debaters. T: You are right. Do you want to know more details about a debate? S: Yeah. Ask the students to read the debate rules. T: OK. Stop reading. Here are some questions for you. Question 1: What is the definition of debate? Ss: A debate is an activity in which students can discuss two sides of an issue. There is a chairperson to charge it. T: Question 2: Tell me the process of a debate in your own words. S: The leading debater who supports the topic speaks first, then another one who disagrees with the topic speaks, then other people take turns to give a free discussion. Towards the end of the debate, the last speaker of each side will summarize the arguments that have been made to support their point of view. T: Excellent, thanks for your answer. In our textbook there is an example of debate, read the topic carefully and discuss the questions with your partner. And I will divide you into two teams. One side agrees with the medical cloning and the other side is against the medical cloning. Then show the questions. Give students 6 minutes to prepare their answers. Team A:

1. What’s their argument?

2. Two reasons for medical cloning.

3. Do you agree with them? Why? Team B:

1. What’s their argument?

2. Two reasons against medical cloning.

3. Do you agree with them? Why? Sample answers:

Team A:

Q1: They support the idea that there should be medical cloning.

Q2: a. There is no danger of the body refusing to accept the new calls.

b. Patients can be treated immediately.

Q3. Yes, I agree with them. Because the medical cloning can help our human beings to cure many diseases. With the help of the cloning techniques, people can be restored to perfect health and be able to live a good life. No, I disagree with them. I think all animals including human beings are natural things on the earth. We should not damage this natural rule. Team B:

Q1. They disagree that there should be medical cloning.

Q2. a. It brings many ethical problems.

b. Many scientists are also worried about the efficiency of the system.

Q3. Yes, I agree with them. Because the medical cloning brings many serious problems to our human beings. We must be very cautious about cloning until these problems are solved. No, I disagree with them. Because all of us want to lead a meaningful life. We should try our best to realize our dream.

Step Ⅲ Speaking task T: Just now, we learned how to organize a debate, now it’s our turn to continue the debate. The topic of our debate is “should we clone?” Now choose the team you agree with. Divide the whole class into four groups, two agree and two disagree. T: To begin this debate, I will give you some information about clone. You can choose what you need. During the speech, you can make notes so that you do not forget what you want to say. In our debate the person who speaks last must summarize your ideas. Here are some tips for you. Show the following.

Center on the subject of the debate. Organize main ideas that support your point of view.

List your own ideas. Make a conclusion. Ask the students to read the following information Show the following.

Why should we use cloning?

The goals and purposes for cloning range from making copies of those that have deceased to better engineering the offspring in humans and animals. Cloning could also directly offer a means of curing diseases or a technique that could extend means to acquiring new data for the sciences of embryology and how organisms develop as a whole over time. Currently, the agricultural industry demands nuclear transfer to produce better livestock. Cloning could massively improve the agricultural industry as the technique of nuclear transfer improves. The goal of transgenic livestock is to produce livestock with ideal characteristics for the agricultural industry and to be able to manufacture biological products such as proteins for humans. Researchers can harvest and grow adult cells in large amounts compared to embryos. Scientists can then genetically alter these cells and find which ones did transform and then clone only those cells. Scientists also ponder the idea of cloning endangered species to increase their population. The possibilities are endless. However, we are actually doing much of this research for the improvement of life for humans. Scientists foresee the cloning of pigs that will produce organs that will not be rejected by humans. Cloning also provides better research capabilities for finding cures to many diseases. There are also possibilities that nuclear transfer could provide benefits to those who would like children. For instance, couples who are infertile, or have genetic disorders, could use cloning to produce a child. Equally important, women who are single could have a child using cloning instead of in-vitro fertilization or artificial insemination. Cloning could also provide a copy of a child for a couple whose child had died. Why should we not use cloning?

The biggest problem with the use of cloning on a large scale is the decline in genetic diversity. Think about it, if everyone has the same genetic material, what

happens if we lose the ability to clone. We would have to resort to natural reproduction, causing us to inbreed, which will cause many problems. Also, if a population of organisms has the same genetic information, then the disease would wipe out the entire population. Helping endangered species by cloning will not help the problem. Currently, zoologists and environmentalists trying to save endangered species are not so much having trouble keeping population numbers up, but not having any animals to breed that are not cousins. The technique of nuclear transfer is also early in its developmental stages. Thus, errors are occurring when scientists carry out the procedure. For instance, it took 277 tries to produce Dolly, and Roslin scientists produced many lambs with abnormalities. If we tried to clone endangered species we could possibly kill the last females integral to the survival of a species. This may be the main reason science is holding out on cloning humans.

Other arguments for cloning include if we are taking nature into our own hands by cloning animals or people. People question when we will draw the line for getting involved in natural events. Religious organizations consider nuclear transfer to cause men to be reproductively obsolete. This claim was deduced by gathering of the information that cloning requires only oocytes, any cell, and a woman to develop in. They also claim that cloning does not respect the fact that humans have souls. They also consider cloning unnatural, and say we are taking the work of God into our own hands. There is also a debate as to the moral rights of clones. Some say their rights will be defied because clones are not granted the birth of newness. We would not receive clones with such excitement as a child of a couple who conceived naturally. If natural reproduction were to occur, genetic variation would occur. They say cloning would deprive a person of uniqueness. They argue that identical twins are not unique from each other, but that they are new in genetic variation and unique from anything that came before them. People also wonder what mental and emotional problems would result if a clone was to find out that he or she was cloned.

Then give students 10 minutes to prepare, everyone finds their roles in the debate. As a chairperson, the teacher is in charge of the debate. Ask the students to do as follows:

First leading speaker gives an argument. Then others give speech freely. Last the fourth speaker gives a summary. Chairperson: From our debate, we really can learn much. All of you have performed well. Whether can we clone? This is a long term argument. To me, if people can use this method properly, it’s really useful, but if we use it in other ways, it can bring us disaster.

Sample notes:

arguments for cloning

1) Cloning will be beneficial to humans. For example, if a couple can’t have children, cloning could help give them a child;

2) we could use cloning to cure illnesses.

arguments against cloning

1) health risks from mutation of genes;

2) emotional risks;

3) risk of abuse of the technology;

4) against nature;

5) cloned animals get ill and die quite young;

6) people are afraid of that scientists will create thousands of copies of the same person;

7) Cloning is dangerous because scientists my create monsters by mistake. Sample speech 1:

The topic of my speech is: Cloning should be banned. If I had the power, I would ban cloning for several reasons.

Firstly, it is against nature and dangerous. Any living things have life and death recycle periods, which promote the evolution of life. The cloning technique is extremely risky right now. An abnormal baby would be a nightmare come true. And people are worried about the possibility that the genetic material used from the adult will continue to age so that the genes in a newborn baby clone could be 30 years old or more on the day of birth. Also monsters may be created by mistake. According to a

survey, 29 European countries do not permit medical cloning. Secondly, people are afraid of that scientists will create thousands of copies of the same person. There are powerful leaders in every generation who will seek to abuse this technology for their own purposes. Going ahead with cloning technology makes this far more likely. What would happen if Hitler was cloned? That would mean more severe disasters and destruction upon human civilization. Thirdly, cloning will result in high emotional risks. Just think: a child grows up knowing her mother is her sister, her grandmother is her mother. Her father is her brother-in-law. Every time her mother looks at her she is seeing herself growing up. The family environment and relationship will be totally different. What kind of pressures will the child feel?

All in all, I would determinedly ban cloning if I had the power.

Sample speech 2:

The topic of my speech is: Cloning should be encouraged

As for myself, I would encourage cloning. There are several reasons.

Firstly, cloning will be beneficial to humans. For example, if a couple can’t have children, cloning could help give them a child. Secondly, we could use cloning to cure illnesses. For example, if there is something wrong with some part of a human body, we could clone a healthy one to replace it. For another, if a child is seriously ill or disabled, we could clone another one. According to a survey, 67% of over 1,000 people want medical cloning to continue in America. And in Britain and China medical cloning has been allowed. Thirdly, clone technology could be used in other ways. For example, we can save the endangered animals by cloning.

In a word, cloning technology has a promising future. I would encourage it if I had enough power.

Step Ⅳ Writing T: Imagine that you are the reporter on a local newspaper and you have been asked to write an article on this debate. To do this you must mention both sides of the argument. Remember to make a large main heading and then a small heading below it. Write around 250 words. Organize your writing in this way: Paragraph 1: the topic of the debate and who won

Paragraph 2: the ideas of the winning side

Paragraph 3: the ideas of the other side Paragraph 4: conclusion and your reaction to the debate, together with any idea you feel they left out A sample version: Should Medical Cloning be Allowed

A debate between Beijing Normal University and Nanjing University In December 26th 2005, there is a debate between Beijing Normal University and Nanjing University. The two teams began their argument about the cloning techniques. The topic of this compotation is: Should medical cloning be allowed? After the fierce debate, Beijing Normal University — the positive side win this compotation.

The view of the positive side is: there should be medical cloning. The view of the negative side is: there should not be medical cloning.

This debate is very successful. As the coin has two sides, every technology can bring the advantages to our society, and also can bring the negative effects to our human beings. So when we judge a new technology good or not good, we should look at whether there are more advantages than its disadvantages or not. If we use it in a proper way it can benefit our human beings a lot. Step Ⅴ Homework T: Now you’ve known how to make a debate. Why don’t you arrange one with your classmates? Choose whichever topic interests you but make sure that it is popular topic. Organize it as you have been shown in this unit. Enjoy the argument and let the better side win! Teacher can give the students some issues to infer: Should students use phones in schools? Should students wear school clothes? Should senior 3 students have PE class? Protect ourselves first or save others first? Save money or pre-consume? Should students have extra-class during their holiday?

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I. Reading comprehension:

Hello, Dolly!

British scientists have done something that many people thought was impossible: they created the first clone of an adult mammal. The clone, named Dolly, is a seven-month-old sheep, grown from a cell of an adult female sheep.

What is a clone? A clone is a copy, a genetic copy. Genes are the instructions for life. They tell a cell what to do and how to do it. Genes make each individual plant or animal different and unique. But a clone has the same genes as the original organism.

Cloning is not new. Plants have been cloned for centuries. New plants are often grown from cuttings from another plant. Also, plants like pineapples, strawberries and carnations are sometimes cloned. One benefit of cloning is that we can make many copies of the best and healthiest plants.

It has been much more difficult to clone animals. Frogs have been cloned, but they died as tadpoles, never living long enough to become adult frogs. Mice, sheep and cattle have been cloned from embryos. But Dolly is the first healthy clone of an adult mammal. How did they do it? (1) An unfertilized egg was taken from a sheep. (2) The egg nucleus was removed. (3) A cell was taken from the udder of a pregnant sheep. It was “starved”, so that it stopped growing. (4) The two cells were combined into one and then implanted in a third sheep, where it grew normally. (5) The clone was born. It was genetically identical to the pregnant sheep in step (3).

This sounds much easier than it actually was. To end up with one clone, the scientists started with 277 udder cells. And they needed in a way to make the egg cell accept a new nucleus. They did that by starving the cell in step (3).

It may soon be possible to clone many types of animals. Will we also be able to clone human organs, or even whole human beings? We have only begun to think

about the morality of cloning technology. Maybe the question to ask is not whether we can clone humans, but instead, should we clone humans? 1. Dolly is a sheep because she is grown from a cell of an adult female sheep _____. A. that has not her father

B. that has not her mother

C. that has no parents

D. that has not any tail 2. Tell which of the following statements is TRUE. A. Only plants can be cloned. B. Only strawberries and carnations can sometimes be cloned. C. Animals and plants have quite a long history of cloning. D. Genes can tell a cell what to do and how to do it during cloning. 3. From the fourth paragraph we can know that _____. A. a tadpole is the early stage of a grown-up frog B. a tadpole is a frog without a tail C. a tadpole is a pool where frogs can live D. a tadpole is a clone of an adult mammal 4. What is the right order in the process of the clone of Dolly? a. Taking an unfertilized egg from an adult female sheep. b. Removing the egg’s nucleus.

c. Combining the two cells into one and then implanting it in a third sheep. d. Taking a cell from the udder of a pregnant sheep. A. a b c d

C. a b d c

答案与分析

本文是科普时文阅读。全文讲述了克隆羊多莉的出生过程。

1. C 从文章中可以看出，多莉是从一只成年羊的细胞中克隆出来的，所以它

B. c a b d D. d c b a 根本没有父母，而是那只羊的一个翻版。A项“它没有父亲”、B项"它没有母亲"说得太片面，D项“它没有尾巴”不符合题意。

2. D 题意为“下面哪句话是对的”，D项“基因在克隆过程中可以告诉细胞做什么及如何去做”，文中第二

段正是说的这个意思。第三段指植物可以克隆，第四段指动物也可以克隆，所以选项A“只有植物可以克隆”不正确。从文中第三段可知菠萝也是可以克隆的，所以B项“只有草莓和康乃馨有时可以克隆”不正确。第三段中指植物已有几个世纪的克隆历史，而没有提到动物的克隆历史，所以与C项“动、植物都有一个相当长的克隆历史”与题意不符。

3. A 文中第四段第二句中说：人们曾经克隆过青蛙，但在蝌蚪阶段就死了，并没有活到成年青蛙阶段，所以我们可以判断，蝌蚪是青蛙的早期形态，故A项“蝌蚪是成年青蛙的早期形态”正确。B项“蝌蚪是没有尾巴的青蛙”、C项“蝌蚪是青蛙生存的池塘”、D项“蝌蚪是成年哺乳动物的克隆体”与实际不符。

4. C 题意为“克隆多莉的正确顺序是什么”，从文中第四段后半部分的内容可知，正确顺序应是C项中所说的。

Ⅱ. About Cloning

Quite a few people might take a negative attitude towards cloning. They argue that cloning will arouse a lot of moral and ethical problems and that some people would use the technique to develop crime (How will you feel to face a younger but identical twin of you yourself?). All that they worry about are true. But as every coin has two sides, cloning is no exception.

Even the father of the world’s first clone Dolly is not for cloning. But he simply goes against cloning people.

But what is clone anyway? Up to now Dolly is the only clone in the world. She was created not out of the natural way the union of a sperm and an egg that we are familiar with, but out of the genetic material from an udder cell of a six-year-old sheep. The embryologist Wilmut fused the udder cell with an egg from another sheep, after first removing all genetic material from the egg. The udder cell’s genes took up residence in the egg and directed it to grow and develop and an identical twin of the original sheep, Dolly was resulted. And that is how a clone is born.

As cloning is no longer a science fiction, and with the birth of Dolly, the whole world begins to focus on these high technology and that generate a severe argument mentioned at the beginning of the article. Is it that frightening when speaking of

cloning? The answer is yes.

I’m not denying that clone has certain disadvantages. Actually clone is a double-edge sword, we have to admit. But we can make the best of its bright side. Will you admire the rose’s beauty as you used to when you discover its thorn? We all know that it is just because the rapid development of economy that has led to the polluted environment and therefore brings a lot of diseases and many an animal’s dying out. Can we just stop modernizing because of this? The answers are certainly no. Such is the case as cloning. We can gain a lot from it if used properly. We can clone organs patients need badly to help reduce their pain and even save their lives because they are the perfect match. We can also make an extinct creation back to live when necessary. The list goes on and on.

There are never going be sufficient reasons that we should stop doing research on the field of cloning. Instead, the future of cloning is prosperous.

Since the harm can not be avoided, at least we can try to put it to the least. But it turns out to be the government’s duty. In addition, the clone technique has not grown mature yet. What troubles us now is really how to make the program a successful one.

Take a second thought, and you might be for cloning too. Ⅲ. Questions about Cloning 1. Why clone? Research advances over the past decade which have told us that, with a little work, we humans can clone just about anything we want, from frogs to monkeys and probably even ourselves! So, we can clone things, but why would we want to? Let’s look at some of the reasons people give to justify cloning.

A. Cloning for medical purposes Of all the reasons, cloning for medical purposes has the most potential to benefit large numbers of people. How might cloning be used in medicine?

a. Cloning animal models of disease Much of what researchers learn about human disease comes from studying animal models such as mice. Often, animal models are genetically engineered to carry disease-causing mutations in their genes. Creating these transgenic animals is a

time-intensive process that requires trial-and-error and several generations of breeding. Cloning technologies might reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study. b. Cloning stem cells for research Stem cells are the body’s building blocks, responsible for developing, maintaining and repairing the body throughout life. As a result, they might be used to repair damaged or diseased organs and tissues. Researchers are currently looking toward cloning as a way to create genetically defined human stem cells for research and medical purposes.

c. “Pharming” for drug production

Farm animals such as cows, sheep and goats are currently being genetically engineered to produce drugs or proteins that are useful in medicine. Just like creating animal models of disease, cloning might be a faster way to produce large herds of genetically engineered animals. B. Reviving endangered or extinct species Have you seen Jurassic Park? In this feature film, scientists use DNA preserved for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and fiercer than expected. Could we really clone dinosaurs? In theory? Yes. What would you need to do this? A well-preserved source of DNA from the extinct dinosaur and a closely related species, currently living, that could serve as a surrogate mother. In reality? Probably not. It’s not likely that dinosaur DNA could survive undamaged for such a long time. However, scientists have tried to clone species that became extinct more recently, using DNA from well-preserved tissue samples.

C. Reproducing a deceased pet No joke! If you really wanted to, and if you had enough money, you could clone your beloved family cat. At least one biotechnology company in the United States offers cat cloning services for the privileged and bereaved, and they are now working to clone dogs. But don’t assume that your cloned kitty will be exactly the same as the one you know and love. The main reason to clone plants or animals is to mass produce organisms with desired

qualities, such as a prize-winning orchid or a genetically engineered animal —

for instance, sheep have been engineered to produce human insulin. If you had to rely on sexual reproduction (breeding) alone to mass produce these animals, and then you would run the risk of breeding out the desired traits because sexual reproduction reshuffles the genetic deck of cards.

Other reasons for cloning might include replacing lost or deceased family pets and repopulating endangered or even extinct species. Whatever the reasons, the new cloning technologies have sparked many ethical debates among scientists, politicians and the general public. Several governments have considered or enacted legislation to slow down, limit or ban cloning experiments outright. It is clear that cloning will be a part of our lives in the future, but the course of this technology has yet to be determined. 2. How are clones created?

The most common process takes DNA from one cell and puts in a hollowed-out egg. Chemicals and electricity are then used to encourage the new DNA to fuse with the egg and develop into an embryo. This technique is called nuclear transfer. 3. Are clones normal, healthy animals? Dolly is, but scientists do not yet know whether this is the exception or the rule. Some early evidence suggests that clones may have health problems and that they may age prematurely. 4. Could a human clone be born soon? In theory, yes. The techniques used to create Dolly could be applied to humans. But the technology of reproductive cloning is still in its very early stages and there is much that scientists do not understand. It took more than 200 attempts to make Dolly. The other embryos failed to implant in the surrogate mother or were miscarried. Even if a clone makes it to birth, at present it has a very low chance of surviving into adult life. 5. Has anyone said they will make live human clones? A number of people have, including Chicago physicist Dr Richard Seed. However, few experts believe that these people have the skills to succeed.

6. Are there any benefits from cloning? Yes. The techniques used have already demonstrated benefits. Polly, another sheep clone at the Roslin Institute in Edinburgh has had a human gene inserted so that it produces a blood clotting agent needed by haemophiliacs in its milk. Cloning of human cells in a laboratory could offer perfectly-matched tissue for surgical or genetic repair of humans.

7. Where does the law stand on live human clones? In the UK, human cloning is already banned(禁止) by law. President Bill Clinton has proposed banning research into producing human clones in the US for five years. Some measures have also been made to establish international agreements banning live human clones. 8. What animals have been cloned?

Scientists have been cloning animals for many years. In 1952, the first animal, a tadpole, was cloned. Before the creation of Dolly, the first mammal cloned from the cell of an adult animal, clones were created from embryonic cells. Since Dolly, researchers have cloned a number of large and small animals including sheep, goats, cows, mice, pigs, cats, rabbits, and a gaur. All these clones were created using nuclear transfer technology.

Hundreds of cloned animals exist today, but the number of different species is limited. Attempts at cloning certain species such as monkeys, chickens, horses, and dogs, have been unsuccessful. Some species may be more resistant to somatic cell nuclear transfer than others. The process of stripping the nucleus from an egg cell and replacing it with the nucleus of a donor cell is a traumatic one, and improvements in cloning technologies may be needed before many species can be cloned successfully.

9. Can organs be cloned for use in transplants?

Scientists hope that one day therapeutic cloning can be used to generate tissues and organs for trans-plants. To do this, DNA would be extracted from the person in need of a transplant and inserted into an enucleated egg. After the egg containing the patient’s DNA starts to divide, embryonic stem cells that can be transformed into any type of tissue would be harvested. The stem cells would be used to generate an organ

or tissue that is a genetic match to the recipient. In theory, the cloned organ could then be transplanted into the patient without the risk of tissue rejection. If organs could be generated from cloned human embryos, the need for organ donation could be significantly reduced. Many challenges must be overcome before “cloned organ” transplants become reality. More effective technologies for creating human embryos, harvesting stem cells, and producing organs from stem cells would have to be developed. The scientists then harvested fetal tissue from the clones and transplanted it into the donor cow. In the three months of observation following the transplant, no sign of immune rejection was observed in the transplant recipient. More research is needed to study the transplantation of organs from “knock-out” pigs o other animals.

10. What are the risks of cloning?

Reproductive cloning is expensive and highly inefficient. More than 90% of cloning attempts fail to produce viable offspring. More than 100 nuclear transfer procedures could be required to produce one viable clone. In addition to low success rates, cloned animals tend to have more compromised immune function and higher rates of infection, tumor growth, and other disorders. Japanese studies have shown that cloned mice live in poor health and die early. About a third of the cloned calves born alive have died young, and many of them were abnormally large. Many cloned animals have not lived long enough to generate good data about how clones age. Appearing healthy at a young age unfortunately is not a good indicator of long term survival. Clones have been known to die mysteriously. For example, Australia’s first cloned sheep appeared healthy and energetic on the day she died, and the results from her autopsy failed to determine a cause of death. Problems also may result from programming errors in the genetic material from a donor cell. 11. Should humans be cloned?

This is a serious topic. I read a report (Reuters, United Nations, October 8, 2004) about the human cloning. A group of scientists, doctors and legal experts asked the United Nations on Wednesday to seek an advisory opinion from the World Court declaring human cloning to be a “crime against humanity.” Physicians from the American Medical Association and scientists with the American Association for the

Advancement of Science have issued formal public statements advising against human reproductive cloning. Currently, the U.S. Congress is considering the passage of legislation that could ban human cloning. In China, the Chinese Government has officially banned research on human cloning for procreation purposes, but allowed remedial cloning.

12. What benefits can humans gain from cloning? Research advances over the past decade have told us that, with a little work, we humans can clone just about anything we want, from frogs to monkeys and probably even ourselves! So, we can clone things, but why would we want to? Let’s look at some of the reasons people give to justify cloning. 1. Cloning for medical purposes 2. Reviving endangered or extinct species 3. Reproducing a deceased pet. Of all the reasons, cloning for medical purposes has the most potential to benefit large numbers of people. 13. How might cloning be used in medicine? Much of what researchers learn about human disease comes from studying animal models such as mice. Cloning technologies might reduce the time needed to make a transgenic animal model, and the result would be a population of genetically identical animals for study. Researchers are currently looking toward cloning as a way to create genetically defined human stem cells for research and medical purposes. Farm animals such as cows, sheep and goats are currently being genetically engineered to produce drugs or proteins that are useful in medicine. Just like creating animal models of disease, cloning might be a faster way to produce large herds of genetically engineered animals.

14. Could humans be cloned now? Unquestionably, yes. Since the first cloned sheep, Dolly, surprised the world back in 1997, the cloning of animals has become almost routine. Companies have been able to churn out cloned cows, goats, and other critters, some of them genetically engineered to make valuable pharmaceutical products. “With cows, it has been very easy to do,” says Princeton biology professor Lee Silver. Human biology is even better understood than that of cows, so the cloning of people

is pretty much inevitable. Indeed, the actual procedure is only a small step beyond what’s already routinely done in test tube baby clinics.