Instead of advancing the public discussion of biotechnology, David Shenk succeeds merely in displaying his general ignorance and unfounded fears in his recent article “Biocapitalism”. His claim that “no living creature has ever before been able to upgrade its own operating system” ignores transduction(the act or process of transferring genetic material or characteristics from one bacterial cell to another) and bacterial conjugation(the temporary union of two bacterial cells), which are ways organisms have “upgraded” their own genomes with novel DNA for hundreds of millions of years. A first-year biology major could have told him that. For Shenk to suggest that his daughter may someday use a before-birth genetic test for “quick-wittedness” is extremely dull-witted, ignoring the complexity of polygenetic traits while embracing a shallow genetic determinism. Nurture-utterly absent from his discussion-really does matter． Finally, worrying about the effects on the gene pool of a “culture in which millions choose the same desirable genes” is worse than pointless. The United Nations projects an approximate human population of eight billion by the year 2020．Even if Shenk's worst fears are realized, and the wealthy parents of 100 million children can and do select for a polygenetic trait-say, blue eyes-this would represent only a modest shift in the gene pool of 1 in 80, or 1．25 percent, assuming that none of those children would otherwise have been born with blue eyes. But what truly matters for the gene pool in the 1,000-yearlong run is the capacity of this trait to grant reproductive success in subsequent generations. Whatever advantage blue eyes currently grant in acquiring a mate presumably derives in part from the trait's relative scarcity. Elementary economics shows that if you flood the market with an asset, you diminish the relative value of that asset: more blue eyes will make blue eyes less sexy. Is it really too much to expect familiarity with either biology or economics from an essay entitled “Biocapitalism”? 86．The purpose of David Shenk's writing is most probably to______． A．draw the public's attention to “Biocapitalism” B．cover his general ignorance about “Biocapitalism” C．show his approval of the advancement in biotechnology D．report his success in biotechnological research 87．According to the author, David Shenk's claim about the upgrading of living creatures______． A．is obviously a fault B．is comprehensible to college students C．is identical to his own argument D．will be testified by his daughter 88．What does David Shenk worry about? A．The capacity of the gene pool． B．The nurture of subsequent generations． C．The dramatic increase of world population． D．The consequences of excessive genetic shifts． 89．Talking about the preference for blue eyes, the author argues that______． A．blue eyes are purely inherited B．few people will have blue eyes C．blue eyes will be less sexy D．people with blue eyes are usually wealthy 90．The tone of this passage is mainly______． A．humorous B．of a matter-of-fact C．bitter and ruthless D．emotional

第1题

Are organically grown foods the best food choices？ The advantages claimed for such foods o

ver conventionally grown and marketed food products are now being debated. Advocates of organic foods frequently proclaim that such products are safer and more nutritious than others.

The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs. Although most of these claims are not supported by scientific evidence, the greater number of written material advancing such claims make it difficult for the general public to sep arate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form. the basis for folklore.

Almost daily the public is surrounded by claims for "no-aging" diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural vitamins are superior to synthetic ones, that crops grown with organic fertilizers are nutritionally superior to chose with chemical fertilizers, that untreated grains are better than fumigated grains, and the like.

One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases consumers are misled if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern ff consumers, particularly those with limited incomes, distrust the regular food supply and buy only expensive organic foods instead.

The author implies that there is cause for concern if consumers with limit ed incomes buy organic foods instead of conventionally grown foods be cause ______ .

A．organic goods can be more expensive but are often no better than conventionally grown foods

B．many organic foods are actually less nutritious than similar conventionally grown foods

C．conventionally grown foods are more readily available than organic foods

D．too many farmers will stop using conventional methods to grow food crops

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第2题

（）is known to all,China will be an（）and powerful country in 20 or 30 years'time.

A.That advancing

B.This advanced

C.As advanced

D.It advancing

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第3题

This principle advancing by Lenin remains a truth.（)

This principle advancing by Lenin remains a truth.()

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第4题

Transistors were a tremendous breakthrough in advancing the computer.（)

Transistors were a tremendous breakthrough in advancing the computer.()

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第5题

_______ is known to all，China will be an _______ powerful country in 20 or 30 years‘

A.A.That;advancing

B.B.This;advanced

C.C.As;advanced

D.D.It;advancing

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第6题

While advancing, we don’t have to keep pulling everything up and keep the tension.（）

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第7题

In countries where a solar calendar was （) the length of each year needed to be modified in order to have the same number of months in each year.

A.progressing

B.proceeding

C.advancing

D.Succeeding

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第8题

By "held back" （Line 1） the author means"__________ "

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A.made to remain in the same class

B.forced to study in the lower class

C.drawn to their studies

D.prevented from advancing

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第9题

Far away around the corner | could see a small female（）advancing towards us.

A.body

B.figure

C.man

D.symbol

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第10题

Our country’s woolen textile industry is forging ahead to meet the needs of the country()。

Our country’s woolen textile industry is forging ahead to meet the needs of the country（)。

A、surpassing rapidly

B、recessing steadily

C、advancing quickly

D、overtaking swiftly

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第11题

In countries where a solar calendar was advancing, the length of each year needed to be modified in order to have the same number of months in each year. (翻译)

In countries where a solar calendar was advancing, the length of each year needed to be modified in order to have the same number of months in each year. （翻译)

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