Cloning: Where Is It Leading Us?
Cloning has always been with us and is here to stay. It is a way of making an exact copy of another animal or plant. It happens in plants when gardeners take cuttings from growing plants to make new ones. It also happens in animals when twins identical in sex and appearance are produced from the same original egg. The fact is that these are both examples of natural clones.
Cloning has two major uses. Firstly, gardeners use it all the time to produce commercial quantities of plants. Secondly, it is valuable for research on new plant species and for medical research on animals. Cloning plants is straightforward while cloning animals is very complicated. It is a difficult task to undertake. Many attempts to clone mammals failed. But at last the determination and patience of the scientists paid off in 1996 with a breakthrough — the cloning of Dolly the sheep. The procedure works like this:
1. Female sheep A provides an egg cell.
2. The nucleus is removed from the egg cell.
3. The egg cell is ready for a new nucleus.
4. Female sheep B provides a somatic cell for the clone. The nucleus of this cell contains all the genes needed to produce a new sheep.
5. The nucleus is taken out of the somatic cell.
6. The nucleus from sheep B and the egg cell from sheep A are joined using electricity.
7. The cell divides and grows into an embryo.
8. The embryo is put into female sheep C, who becomes the carrier of the clone.
9. The lamb is the clone of the donated cell from sheep B which provides the nucleus.
On the one hand, the whole scientific world followed the progress of the first successful clone, Dolly the sheep. The fact that she seemed to develop normally was very encouraging. Then came the disturbing news that Dolly had become seriously ill. Cloning scientists were cast down to find that Dolly's illnesses were more appropriate to a much older animal. Altogether Dolly lived six and a half years, half the length of the life of the original sheep. Sadly the same arbitrary fate affected other species, such as cloned mice. The questions that concerned all scientists were: “Would this be a major difficulty for all cloned animals? Would it happen forever? Could it be solved if corrections were made in their research procedure?”
On the other hand, Dolly's appearance raised a storm of objections and had a great impact on the media and public imagination. It became controversial. It suddenly opened everybody's eyes to the possibility of using cloning to cure serious illnesses and even to produce human beings.
Although at present human egg cells and embryos needed for cloning research are difficult to obtain, newspapers wrote of evil leaders hoping to clone themselves to attain their ambitions. Religious leaders also raised moral questions. Governments became nervous and more conservative. Some began to reform their legal systems and forbade research into human cloning, but other countries like China and the UK, continued to accumulate evidence of the abundant medical aid that cloning could provide. However, scientists still wonder whether cloning will help or harm us and where it is leading us.
A Daughter's Letter
Dear Mum,
Today is my birthday and it is the first birthday I have spent far away from home. I miss you very much.
A few days ago, we learned a poem and discussed the famous line “You don't know what you've got until it's gone.” Miss Li told us that her primary school teacher made a huge difference in her life. She told us how her teacher encouraged her. But she mentioned that she didn't have a chance to tell her. She was sad about this. This made me think a lot, especially when I'm thousands of kilometres away from home. I am writing you this letter because I want you to know how much I love you.
A friend once said that a person's happiness was mostly because of their childhood. I agree with her. I still remember the times when you held my hand and counted steps with me as we walked along. You told me stories about the brave elephant and encouraged me to be a confident girl. I also remember that in our small flat, you read books at your desk and I played with my toys on the bed nearby. In cool autumns, we took many walks along the street, chatting and laughing together. My childhood was filled with these warm memories. Now, I see what an influence you've had on my life.
Time flies and so much has happened. There have been good times and bad times, successes and failures, but you were always by my side. When I won the swimming prize, you smiled and said you were proud of me. When I failed my maths exam, you encouraged me and said that everything would be fine. Your words encouraged me to deal with all my difficulties. Now when I have problems, I always think of your words and they help me so much.
You have always said that we should judge people's success by how they live their lives every day. I think I'm living a successful life and it's all because of you. Thank you, Mum.
Love,
Feifei
Special Occasions
(P=Presenter, J=Jenny, C=Carl)
P: Our Culture Corner this week is on parties, and we have two young people from the UK in the studio. Jenny and Carl, thank you for coming.
J: You're welcome.
C: Thanks for inviting us!
P: As far as I know, young people in the UK like to go to parties. So what kind of parties do you like?
J: I like dinner parties. That means you're invited to someone's house for dinner. It's usually just a group of close friends chatting and having a good time together.
C: Well, I like big parties where you can dance, have fun and meet new people!
P: Right. And could you give us some advice about what to do at parties in the UK?
C: My advice is to dress appropriately. Some parties are held for a specific formal purpose, like a graduation party or a wedding. Some may be informal, like a small dinner or birthday party. So if it's a formal occasion, you should dress smartly. Wear a neat black suit and a tie, for example.
J: Yes, but if it's just an informal party, you can wear anything you want, like T-shirts and jeans.
P: I see. And are there any rules for attending parties in general? You know, adults like us might sometimes bring a bottle of wine or some beer. What about teenagers like you?
C: General rules? We'd usually bring something like snacks or puddings. And try not to be late! You should always be on time.
J: Also, when you arrive, it's polite to say hello and thank the host for inviting you. If you don't know them well, you should introduce yourself and make small talk. And say goodbye and thank them again when you leave.
C: And if it's a graduation party or a wedding, don't forget to offer your congratulations and good wishes. It's also important to make an effort to talk to other people.
P: Sounds like some great advice there. Now ...