Question

17．Back in the 1860s，a British scientist named Henry Walter Bates noticed something interesting in the animal world：some harmless animals change the color or patterns of their skin to pretend to be deadly．For example，a kind of butterfly，Common Mormon，can change the pattern on its wings so that it looks like another butterfly species，the Common Rose，which is poisonous for birds to eat．
    Bates argued that animals develop this ability to protect themselves from being eaten．This theory had been widely accepted by scientists．But one question remains：how do these animals manage to do that？
    After more than 150 years，scientists are finally able to answer that question-it is all down to a gene called"doublesex"，according to a study published on March 6 in the journal Nature．
    In fact，scientists have long known that genes are responsible for this useful ability．Just like your hair color and the shape of your eyes are determined by your genes，the patterns on a butterfly's wings can be explained similarly．But until the new study，scientists hadn't been able to find out which genes in particular were responsible．
    Encouraged by the development of new technologies for studying genes，scientists at the University of Chicago，US decided to give it another try．They compared the genetic structure of the Common Mormons that changed their wing patterns with those of ones that did not．And all the results pointed to a single gene，"doublesex"．
This was much to the scientists'surprise．They used to expect that something as complex as this would be controlled by many different genes．For example，one gene would control the color of the upper part of the wing，one would do so for the lower part and one would control wing shape．
    However，the"doublesex"gene doesn't quite do everything by itself．Instead，it acts like a switch-it"tells"other genes to change the wing patterns．Isn't that clever？
    Scientists believe that this special ability of the"doublesex"gene was developed throughout the long history of evolution．"The harmless species gains an advantage by resembling something predators （捕食動物） avoid，"Sean Carroll，a scientist at the University of Wisconsin-Madison，US told Nature．"It was obvious evidence for natural selection．"
63．What was newly discovered by scientists at the University of Chicago？D
A．Some animals can change their skin color．
B．Some butterflies can disguise themselves as other species．
C．Genes are responsible for the change in animals'skins．
D．Common Mormons change their skin patterns due to a certain gene．
64．What surprised scientists in the study？C
A．So many genes are involved in the change of patterns．
B．The genetic structure of the butterflies is so complex．
C．A single gene determines the change of patterns．
D．The gene"doublesex"singlehandedly changes the wing patterns．
65．Which of the following is the best title？B
A．A new discovery                  
B．How butterflies stay safe
C．A gene called"doublesex"
D．Natural selection．

Answer 1

分析 本文屬于科普文，科學(xué)家通過對Common Mormon這種蝴蝶顏色可以變化的研究，得到科學(xué)界的一個(gè)新的發(fā)現(xiàn)，發(fā)現(xiàn)決定蝴蝶顏色變化的是單個(gè)基因doublesex，這糾正了了科學(xué)家以前對基因的認(rèn)識．

解答 DCB
63．答案 D 細(xì)節(jié)理解題 根據(jù)第五段They compared the genetic structure of the Common Mormons that changed their wing patterns with those of ones that did not．And all the results pointed to a single gene，"doublesex"．可知University of Chicago的新發(fā)現(xiàn)是Common Mormons 改變顏色是由于單個(gè)基因doublesex的緣故，故答案為D
64．答案 C 細(xì)節(jié)理解題 根據(jù)They used to expect that something as complex as this would be controlled by many different genes．For example，one gene would control the color of the upper part of the wing，one would do so for the lower part and one would control wing shape，可知，科學(xué)家以前的判斷是錯(cuò)的，復(fù)雜的部分也可以由單個(gè)基因來覺得故答案為C
65．答案 B 主旨大意題 根據(jù)全文可知，科學(xué)家通過對Common Mormon這種蝴蝶顏色可以變化的研究，得到科學(xué)界的一個(gè)新的發(fā)現(xiàn)，發(fā)現(xiàn)決定蝴蝶顏色變化的是單個(gè)基因doublesex，這糾正了了科學(xué)家以前對基因的認(rèn)識，故答案為B

點(diǎn)評 1、要想做好科普英語閱讀理解題，同學(xué)們就要注意平時(shí)多讀科普知識類文章，學(xué)習(xí)科普知識，積累常見的科普詞匯，從根本上提高科普英語的閱讀能力．
2、要熟悉科普類文章的結(jié)構(gòu)特點(diǎn)．科普類文章一般由標(biāo)題（Head line），導(dǎo)語（Introduction），背景（Back ground），主體（Main body）和結(jié)尾（End）五部分構(gòu)成．標(biāo)題是文章中心思想高度而又精辟的概括，但根據(jù)歷年的高考情況來看，這類閱讀理解材料一般不給標(biāo)題，而要同學(xué)們選擇標(biāo)題．導(dǎo)語一般位于整篇文章的首段．背景交待一個(gè)事實(shí)的起因．主體則對導(dǎo)語概括的事實(shí)進(jìn)行詳細(xì)敘述，這一部分命題往往最多，因此，閱讀時(shí)，同學(xué)們要把這部分作為重點(diǎn)．結(jié)尾往往也是中心思想的概括，并與導(dǎo)語相呼應(yīng)，命題者常在此要設(shè)計(jì)一道推理判斷題．　　
3、在進(jìn)行推理判斷時(shí)，同學(xué)們一定要以閱讀材料所提供的科學(xué)事實(shí)為依據(jù)，同時(shí)所得出的結(jié)論還應(yīng)符合基本的科普常識．