Question

20．Special trees that grow faster，fight pollution，produce better wood，and even sense chemical attacks are being planted by scientists in the US．
When 40 per cent of Hawaii's US 14 million-a-year papaya （木瓜）industry was destroyed by a virus five years ago，work began on creating genetically engineered （轉(zhuǎn)基因的） trees．
Researchers successfully introduced seeds that were designed to resist the virus．Since then，more and more people have been testing genetically engineered trees．
Some researchers put special bacteria into trees to help them grow faster and produce better wood．Others are trying to create trees that can clean polluted soil．
Meanwhile fruit farmers are looking for trees that are strong enough to resist worms，and paper companies want trees that produce more wood and therefore more paper．
The Pentagon （五角大樓） even gave the researchers US 500，000this year after they developed a pine tree that changes its colours if it senses a chemical attack．
So far，the poplar，eucalyptus （楊樹與桉樹），apple and coffee trees are among those being engineered．All this can be done today because we have a better understanding of tree genomes （基因組）．
However，some people fear that the genetically engineered trees will cause dangerous results．They are worried that the new trees will breed with natural species and change the balance of the forest environment
"It could be destructive，"said Jim Diamond，an environmentalist．"Trees are what is left of our natural environment and home to many endangered species．"
But researchers insist that science could give nature a fighting chance against both natural and man-made dangers．
They hope to answer the critics by stopping the new trees from breeding，so their effect on the environment can be controlled．
57．Which kind of tree is not the ones that scientists are planting in the US？C
A．Trees that worms can't hurt．
B．Trees that can protect themselves at a chemical attack．
C．Trees that can resist wind better．
D．Genetically engineered trees．
58．What caused the American scientists to work on special trees？B
A．They think science could give nature a fighting chance against both natural and man-made dangers．
B．Great numbers of trees have been lost due to attacks by viruses．
C．Researchers successfully introduced seeds designed to resist the virus．
D．Tree genomes are mapped out so scientists know how to improve trees．
59．Which of the following was probably the first kind of trees being engineered？A
A．Papaya．B．Pine．C．Apple．D．Poplar．
60．Why did critics think engineered trees dangerous？BecauseD．
A．these trees can destroy the balance of nature
B．everything except trees has been genetically engineered
C．trees are home to many endangered species
D．these trees may affect normal trees．

Answer 1

分析 美國科學(xué)家最近研制出了一些特殊樹種，這些樹可以抗污染、出產(chǎn)更多的木材、能夠察覺到化學(xué)物質(zhì)的侵害．但是有些人害怕這種轉(zhuǎn)基因的樹種會與原先的自然樹種進(jìn)行雜交，從而威脅到自然物種，最終造成森林環(huán)境的破壞．

解答 57．C細(xì)節(jié)理解題．通過文章第三段Meanwhile fruit farmers are looking for trees that are strong enough to resist worms；第四段中they developed a pine tree that changes its colours if it senses a chemical attack和So far，the poplar，eucalyptus，apple and coffee trees are among those being engineered．可以判斷只有C選項中抗風(fēng)的樹木沒有在美國種植，故答案選C．
58．B細(xì)節(jié)理解題．根據(jù)文章第二段內(nèi)容When 40 per cent of Hawaii's US$14 million-a-year papaya industry was destroyed by a virus five years ago，work began on creating genetically engineered trees．可以判斷是由于木瓜產(chǎn)業(yè)受到了病毒的危害，研究人員才開始了轉(zhuǎn)基因樹種的研究工作，故答案選B．
59．A細(xì)節(jié)理解題．從文章第二段內(nèi)容可知自從五年前木瓜產(chǎn)業(yè)受到病毒危害后，研究轉(zhuǎn)基因樹種的工作就開始了，由此判斷木瓜是首先被研究的轉(zhuǎn)基因樹種，答案選A．
60．D 細(xì)節(jié)理解題．根據(jù)文章倒數(shù)后三段段內(nèi)容They are worried that the new trees will breed with natural species and change the balance of the forest environment．可知人們反對種植這種樹的原因是害怕這些樹會和普通樹木雜交從而會影響森林環(huán)境，故答案選D．

點(diǎn)評 本文講述了美國科學(xué)家最近研制出了一些特殊樹種，這些樹可以抗污染、出產(chǎn)更多的木材、能夠察覺到化學(xué)物質(zhì)的侵害．但是有些人害怕這種轉(zhuǎn)基因的樹種會與原先的自然樹種進(jìn)行雜交，從而威脅到自然物種，最終造成森林環(huán)境的破壞．的一個故事，題目涉及多道細(xì)節(jié)理解題，做題時結(jié)合原文和題目有針對性的找出相關(guān)語句進(jìn)行仔細(xì)分析，結(jié)合選項選出正確答案．推理判斷題也是要在抓住關(guān)鍵句子的基礎(chǔ)上合理的分析才能得出正確答案，切忌胡亂猜測，一定要做到有理有據(jù)．