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?
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?
1. 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(变异) in their genes. Creating these transgenic(转基因的) animals is a time-intensive process that requires trial-and-error and several generations of breeding(培育). 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.
2.Cloning stem cells(干细胞) for the treatment of diseases
Stem cells are the body's building blocks, responsible for developing 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 up cloning as a way to create certain human stem cells for the research of diseases.
3. Cloning farm animals 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.
1.From Purpose One, we can infer that .
A.most transgenic animals are clone
B.most animals carry engineered genes
C.most transgenic animal models are not cloned
D.most animals carry disease-causing mutations in their genes
2.It can be learned from Purpose Two that cloning technologies can be mainly use do .
A.create damaged or diseased organs and tissues
B.clone genetically defined human stem cells
C.develop and maintain the body
D.repair the body throughout life
3.According to Purpose Three, cloning technologies can be mainly used to .
A.speed up the producing of genetically engineered animals
B.produce drugs or proteins that are useful in medicine
C.raise genetically engineered cows, sheep and goats
D.produce large herds of animals for human beings
科目:高中英语 来源: 题型:
Scientists have made a major ____ in cancer research.
A. break-in B. breakthrough
C. breakup D. breakdown
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科目:高中英语 来源: 题型:阅读理解
Some people can stay up all night and still get work done the next day. I’m not one of them. After a night without enough sleep, I feel bad-tempered. I have trouble remembering things. And all I want to do is go to bed.
How do you feel after you’ve stayed up late to finish schoolwork or the day after an overnight party? Scientists now say that your answers to these questions may depend on your genes.
New research suggests that a gene called “period 3” influences how well you function without sleep. The “period 3” gene comes in two forms: short and long. Everyone has two copies of the gene. So, you may have two longs, two shorts, or one of each. Your particular combination depends on what your parents passed on to you.
Scientists from the University of Surrey in England studied 24 people who had either two short or two long copies of “period 3”. Study participants (参与者) had to stay awake for 40 hours straight. Then, they took tests that measured how quickly they pushed a button when numbers flashed (闪过) on a screen and how well they could remember lists of numbers.
Results showed that the people with the short form of “period 3” performed much better on these tests than the people with the long form did. In both groups, people performed worst in the early morning.
After the first round of experiments, participants were finally allowed to sleep. People in the group that performed well on the tests (those with the short form of “period 3”) took about 18 minutes to nod off.
While people with the long “period 3” gene fell asleep in just 8 minutes. They also spent more time on deep sleep. That suggests that people with the long form of the gene need more and deeper sleep to keep their brains working in top form.
I think I must have the long form of “period 3”. What about you?
The purpose of this passage might be ___________
A. to tell us the importance of plenty of sleep.
B. to tell the result of a research on sleepy gene.
C. to inform the harm of lacking sleep.
D. to announce the sleeping rules of humans.
What kind of people need less sleep according to the research?
A. Those with two short copies of the gene.
B. Those with two long copies of the gene.
C. Those with one short and one long copy of the gene.
D. Those with three short copies of the gene.
If one lacks enough sleep, one should avoid doing important or dangerous things ___________.
A. at noon B. at night
C. in the afternoon D. at dawn
Why did the writer think he or she had the long form of “period 3”?
A. Because the writer could remain energetic without enough sleep.
B. Because the writer could do things correctly at dawn.
C. Because the writer needed more sleep to keep energetic.
D. Because the writer recovered quickly after sleep.
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科目:高中英语 来源:2015届四川省高二上学期期中考试英语试卷(解析版) 题型:阅读理解
Now, it’s time for some brief news items.
Teens Go Online
Some 13 million European children under 18 use the Internet for schoolwork, games and music according to research done by Nielsen’s “Net-rating”. The study covered Britain, Germany, France, Italy and Spain. Experts advised parents to limit the time their kids spend on line and keep them away from chat rooms.
Chat to the magic Mum
British author J. K. Rowling, mother of magic boy Harry Potter, will do an Internet interview about her new book “Harry Potter and the Half-Blood Prince” on June 26. Before the event, children are invited to send their questions about Harry to the website. The book will hit stores in the US and UK on June 21 and will arrive in China in August.
School Soldiers
Russian school students will have to do basic military training in their final year of school, the government has decided. The lesson will include learning to fire guns, marching drills and how to deal with a chemical, nuclear or biological attack. The activity is seen as part of a drive toward the education of their love for their country.
Is it hard for you to get up early and get ready for classes? Some students at Winter Park High School just roll out of bed in their pajamas (睡衣) and go to class in their own bedrooms, Of course, their teachers and classmates do not see them because all their class work is on the computer. The Florida High School, the state’s only online school, has 250 students who are taking classes at home by computer. Students in this first online program take classes in algebra (代数), American government, chemistry, computer, economics, and web-page design. They also have to go to regular school to attend other classes.
1.In the first news item, which country is NOT covered in the research?
A. Britain. B. France. C. Sweden. D. Spain.
2.What is the second news item mainly about?
A. J. K. Rowling will have an Internet interview.
B. Children will meet Harry Potter’s mother.
C. The Harry Potter book will be available on the Internet.
D. The Harry Potter book will arrive in China in early June.
3.Why will Russian school students have basic military training?
A. To get ready for a military parade.
B. To learn to protect themselves.
C. To gain some military knowledge.
D. To develop their love for the country.
4.The news from Florida can be given a title “____________”.
A. Get up Late B. Online School C. Magical Computers D. No Teachers
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科目:高中英语 来源:2013-2014学年山东省山师附中高三11月期中学分认定考试英语试卷(解析版) 题型:阅读理解
Babies who are slow to gain weight in the first months of their lives generally catch up to their peers by age 13,a large UK study shows, Researchers said the results would make parents whose babies fail to put on weight quickly less worried.
The researchers looked at data from ,11,499 children who took part in a large study, It showed that 507 who were slow to gain weight in the first eight weeks of life recovered fairly quickly and had almost caught up by age 2. Another group of 480 who were slow to gain between eight weeks and nine months continued to put on weight slowly until they were seven years ,but then had a sudden increase and caught up by age 13, The different pattems of recovery between the two groups were likely due to different reasons for slow weight gain ,the researchers said, All the children were still lighter and shorter than their peers by the time they were teenagers ,but within the normal range.
The findings highlight the importance of monitoring a baby’s weight and height gain during the first few weeks and months ,but not creating anxiety with parents of slow-growing babies, said the study leader Prof Alan Emond from the University of Bristol.
“In the past, a lot of parents have been caused unnecessary anxiety by heaith professionals and this is a positive and reassuring message.”He said in many cases of slow growth where children do not follow the standard’curve’(曲线)it is just because they are following their genetic potential.
Dr Simon Newell, vice-president of the Royal College of Paediatrics and Child Health, said he broadly agreed with the concluslons of the researchers but stressed that poor weight gain was something that needed to be monitored closely, “I would encourage parents to use growth charts but if measurements show your baby is smaller than averager it may be completely normal, ”he said.
1.What can we know from the findings of the research?
A、All the cases of slow weight gain in the first months of the babies’ lives are caused by the same reason
B、Slow-growing babies will have the same height and weight with their peers by age13
C、Many cases of children whose growth don’t meet the growing standard curve cannot be treated as abnormal
D、The findings won’t cause parents’ anxiety so monitoring a baby’s growth from his/her birth is unnecessary
2.Which of the following statements is true according to the passage?
A、It’s important to monitor a baby’s weight and height gain for new parents
B、New parents should feel anxious about their baby’s weight and height gain
C、Researches still couldn’t find the reasons for slow weight gain
D、All the children’s weight and height became normal by age 13
3.What does the underlined word in the fourth paragraph mean?
A、Making sure something is certain to be true
B、Making someone calmer and less anxious
C、Confirming something is to happen again
D、Being sure that someone can be attracted
4.Which of the statements would Dr Simon Newell agree to?
A、To some degree, growth charts can help parents monitor their babies’ weight gain
B、It’s abnormal for babies are smaller than average
C、He agreed with the researchers completely
D、Babies’ weight gain can only be monitored and measured by using growth charts.
5.The writer wrote this passage in order to
A、tell us how to help babies grow faster
B、explain why babies are gain weight slowly
C、report on the findings of a research
D、reduce the anxiety of some parents
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科目:高中英语 来源:2014届湖南四县一中高一下学期期中联考英语试卷(解析版) 题型:单项填空
The question came up at the meeting_____ we had enough money for our research.
A. that B. which C. whether D. that if
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