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 （捕食动物） 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 本文属于科普文，科学家通过对Common Mormon这种蝴蝶颜色可以变化的研究，得到科学界的一个新的发现，发现决定蝴蝶颜色变化的是单个基因doublesex，这纠正了了科学家以前对基因的认识．

解答 DCB
63．答案 D 细节理解题 根据第五段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的新发现是Common Mormons 改变颜色是由于单个基因doublesex的缘故，故答案为D
64．答案 C 细节理解题 根据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，科学家以前的判断是错的，复杂的部分也可以由单个基因来觉得故答案为C
65．答案 B 主旨大意题 根据全文可知，科学家通过对Common Mormon这种蝴蝶颜色可以变化的研究，得到科学界的一个新的发现，发现决定蝴蝶颜色变化的是单个基因doublesex，这纠正了了科学家以前对基因的认识，故答案为B

点评 1、要想做好科普英语阅读理解题，同学们就要注意平时多读科普知识类文章，学习科普知识，积累常见的科普词汇，从根本上提高科普英语的阅读能力．
2、要熟悉科普类文章的结构特点．科普类文章一般由标题（Head line），导语（Introduction），背景（Back ground），主体（Main body）和结尾（End）五部分构成．标题是文章中心思想高度而又精辟的概括，但根据历年的高考情况来看，这类阅读理解材料一般不给标题，而要同学们选择标题．导语一般位于整篇文章的首段．背景交待一个事实的起因．主体则对导语概括的事实进行详细叙述，这一部分命题往往最多，因此，阅读时，同学们要把这部分作为重点．结尾往往也是中心思想的概括，并与导语相呼应，命题者常在此要设计一道推理判断题．　　
3、在进行推理判断时，同学们一定要以阅读材料所提供的科学事实为依据，同时所得出的结论还应符合基本的科普常识．