题目内容

【题目】【原创】The first theories and experiments with cloning began in the late 1880s as scientist sought to prove their theories about how the genetic material inside cells worked. Discoveries about the nature of DNA in the 1940s made it possible for cloning experiments to progress. In 1944 it was discovered that genetic information for each cell was kept in the cell’s DNA. When Oswald Avery found this genetic information, it gave scientists new ways to try to clone animals by using that genetic blueprint(生物细胞的模型).

The first cloned animals were northern leopard frogs that were cloned by Thomas J. King and Robert Briggs in 1952. King and Briggs believed, based on their clones, that young cells were more practical for the cloning process. Cells that were taken from adults resulted in abnormally developed tadpoles(蝌蚪). The next successful cloning experiments also resulted in cloned frogs. John Gurdon cloned South African frogs in 1962. His use of adult cells disproved the previous theory that only young cells could be used in the cloning process with success.

While animal cloning had been the focus of cloning experiments, the 1960s also saw other types of cloning. In 1964, F. C. Steward took an adult root cell from a carrot plant and successfully cloned the plant. Throughout the rest of the 1960s, scientists continued to clone frogs and to discover more about DNA. The first gene was discovered in 1969.

In 1977, the first cloned mice embryos were created. The first mammal was cloned in 1984. The cloned sheep was quickly followed in 1985 with cloned cattle embryos. A cow clone was created in 1986 and several calves in 1993. That same year, human embryos were cloned for the first time. In 1995 and 1996, sheep were cloned, including the famous Dolly.

【1】The first paragraph serves as a(n) __________________________.

A. explanation B. conclusion

C. comment D. background

【2】When as the first plant successfully cloned?

A. In 1952 B. In 1960

C. In 1964 D. In1969

【3】How is the passage organized?

A. In order of frequency

B. In order of time

C. In order of importance

D. In order of preference

【答案】

【1】D

【2】C

【3】B

【解析】

试题分析:随着科学技术的发展,克隆技术也成为了人们讨论的热点问题,那么克隆技术到底是怎么客服最初的困难而发展至今的呢?这篇文章将告诉你答案。

【1】D 写作意图题。文章从第二段开始就讲述了科学家是如何克服难关,克隆出动物的过程,以及一些错误的理论如何通过实验而得到纠正,故第一段主要介绍的是克隆技术面临困难这一背景,选择D。

【2】C 细节理解题。根据文章第三段的In 1964, F. C. Steward took an adult root cell from a carrot plant and successfully cloned the plant.可知,选择C。

【3】B 文章结构题。根据文章不断出现的时间,可以推断出文章是按照时间发展的顺序来开展的,故选择B。

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【题目】America’s Beauty Is in Its Diversity

America is built on the idea of freedom, and there is no exception for Muslim women. I the freedom of religion and speech. But mostly, I believe it’s OK to be , and to stand up for who and what you are. So I believe in wearing the hijab.

The hijab is a religious head covering, like a scarf. I am Muslim, and keeping my head covered is a of maturity成熟and respect toward my and to Allah’s will. , I also like to wear it to be different. I don’t usually like to do what everyone else is doing. I want to be a(n) , not just part of the crowd. But when I first wore it, I was also afraid of the that I’d get at school.

I on my own that sixth grade was the I should start wearing the hijab. I was about what the kids would say or even do to me. I thought they might make fun of me, or be scared of me and my headscarf. Kids at that age usually like to be all the same, and there’s little or no of differences.

On the first day of school, I put all those thoughts behind my back and walked in with my head held high. I was holding my breath a little, but I was also proud to be a Muslim, proud to be wearing the hijab, proud to be different.

I was about everything I had thought the kids would say or even do to me. I actually met a lot of people because of wearing my head covering. Most of the kids would come and ask me questions about the hijab and why I wore it.

I did hear some kids were making fun of me, there was one girl----she wasn’t even in my class, and we never really talked much---and she spoke me, and I wasn’t even there! I made a lot of new friends that year, friends that I still have until this very day, five years later.

Yes, I’m different, but everyone is different here, in one way or another. This is the of America.

1A. believe in B. stick to C. carry out D. push for

2【改编】A. independent B. difficult C. different D. sensitive

3A. signal B. sign C. reminder D. cause

4A. religion B. country C. parents D. status

5A. In a word B. In general C. To be brief D. To be honest

6A. princess B. heroine C. individual D. adult

7A. praise B. punishment C. reflection D. reaction

8【改编】A. wished B. unexpected C. realized D. decided

9A. time B. chance C. case D. occasion

10A. disappointed B. scared C. enthusiastic D. angry

11A. still B. already C. even D. ever

12】A. show off B. pull off C. pick up D. put up

13A. rejection B. ignorance C. knowledge D. acceptance

14A. negative B. optimistic C. serious D. strange

15【改编】A. outdoor B. inside C. actual D. outside

16A. concerned B. particular C. wrong D. convinced

17A. respectfully B. cautiously C. suspiciously D. critically

18【改编】A. and B. for C. but D. or

19A. in terms of B. in front of C. in charge of D. in favor of

20A. significance B. beauty C. value D. power

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