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阅读模拟题（6）
Scientists have known since 1952 that DNA is the basic stuff of heredity.
They've known its chemical structure since 1953. They know that human DNA acts
like a biological computer program some 3 billion bits long that spells out the
instructions for making proteins， the basic building blocks of life.
But everything the genetic engineers have accomplished during the past
half-century is just a preamble to the work that Collins and Anderson and
legions of colleagues are doing now. Collins leads the Human Genome Project, a
15-year effort to draw the first detailed map of every nook and cranny and gene
in human DNA. Anderson, who pioneered the first successful human gene-therapy
operations, is leading the campaign to put information about DNA to use as
quickly as possible in the treatment and prevention of human diseases.
What they and other researchers are plotting is nothing less than a
biomedical revolution. Like Silicon Valley pirates reverse-engineering a
computer chip to steal a competitor's secrets, genetic engineers are decoding
life's molecular secrets and trying to use that knowledge to reverse the natural
course of disease. DNA in their hands has become both a blueprint and a drug, a
pharmacological substance of extraordinary potency that can treat not just
symptoms or the diseases that cause them but also the imperfections in DNA that
make people susceptible to a disease.
And that's just the beginning. For all the fevered work being done,
however, science is still far away from the Brave New World vision of
engineering a perfect human—or even a perfect tomato. Much more research is
needed before gene therapy becomes commonplace, and many diseases will take
decades to conquer, if they can be conquered at all.
In the short run, the most practical way to use the new technology will be
in genetic screening. Doctors will be able to detect all sorts of flaws in DNA
long before they can be fixed. In some cases the knowledge may lead to
treatments that delay the onset of the disease or soften its effects. Someone
with a genetic predisposition to heart disease, for example, could follow a
low-fat diet. And if scientists determine that a vital protein is missing
because the gene that was supposed to make it is defective, they might be able
to give the patient an artificial version of the protein. But in other
instances, almost nothing can be done to stop the ravages brought on by genetic
mutations. (409 words)
1. It can be inferred from the text that Collins and Anderson and legions
of colleagues _____.
[A] know that human DNA acts like a biological computer program
[B] have found the basic building blocks of life
[C] have accomplished some genetic discovery during the past
half-century
[D] are making a breakthrough in DNA
2. Collins and Anderson are cited in the text to indicate all the following
EXCEPT that ______.
[A] time-consuming effort is needed to accomplish the detailed map of in
human DNA
[B] human gene-therapy operations may be applied to the patients
[C] gene-therapy now is already generally used to the treatment and
prevention of human diseases
[D] information about DNA may be used in the treatment and prevention of
human diseases
3. The word “pirate” (line 2, paragraph 3) means______.
[A] one who robs at sea or plunders the land from the sea
[B] one who makes use of or reproduces the work of another without
authorization
[C] to take (something) by piracy
[D] to make use of or reproduce (another's work) without authorization
4. We can draw a conclusion from the text that_____.
[A] engineering a perfect human is not feasible for the time being
[B] it‘s impossible for scientists to engineer a perfect tomato
[C] many diseases will never be conquered by human beings
[D] doctors will be able to cure all sorts of flaws in DNA in the long
run
5. The best title for the text may be ______.
[A] DNA and Heredity
[B] The Genetic Revolution
[C] A Biomedical Revolution
[D] How to Apply Genetic Technology
参考答案：D C B A B |
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发表于 2018-8-18 14:25:39