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  3. Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string da

Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string da

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问题               Dorothy Crowfoot Hodgkin
    When Dorothy Crowfoot Hodgkin was ten years old, she watched her first crystals form on a string dangling in a glass of salt water. Many children before and since have done the same, but in Hodgkin’s case, the sparkling geometric shapes kindled a fascination that would lead her to world fame.   In 1964, nearly half a century later, Hodgkin received a Nobel Prize in Chemistry for discovering the structures of penicillin and vitamin B12 from photographic images of their crystals. She made the images with a technique called x-ray crystallography, which involves firing x-rays through a crystal to determine the arrangement of the atoms in it. It is a bit like determining the shape of a jungle gym from its shadow.
    Born in 1910, Hodgkin spent the first few years of her life in Cairo, where her father was an official in the British colonial government. Most of her education had been at home, but once back at school in England, her keen interest in crystals won the attention of her schoolteacher. Hodgkin and a friend got special permission to join the boys studying chemistry. By age 12, she was doing chemistry experiments on rocks she found in her garden to see what they contained.   That summer, while visiting her father in Khartoum, Sudan, she met Dr. A. E. Joseph, a friend of her father’s and a well-known soil chemist. Joseph took her on a tour of his laboratory. Pleased by her intense interest, he put together a small chemistry set for her, which she took back to England and set up in her mother’s attic. It was her first laboratory.
    Hodgkin enrolled at Oxford University,  where she eventually specialized  in x-ray crystallography. At the time, the analysis of the structures of even the simplest chemicals by x-ray crystallography required at least 30 sets of calculations, all done by hand. The work demanded perseverance and diligence, and a good head for math. Under these conditions, Hodgkin flourished.   Seeking a greater challenge after college, Hodgkin went to Cambridge to study with a young crystallographer named J.D. Bernal. Together they solved some of the most complex chemical structures ever attempted, including those of several vitamins and sex hormones. They took the first x-ray photographs of a protein—the stomach enzyme pepsin—showing that proteins form regular crystals.   In 1937, Hodgkin received her doctorate. Within a few months, she also married historian Thomas Hodgkin, taking his name. The Hodgkins were a two-career family, working in different towns and commuting on alternate weekends to see each other. Dorothy Hodgkin remained at Oxford, where she continued her research, taught university classes, and raised three children.   When the demand for penicillin soared during World War Ⅱ, chemists all over the world raced to determine its structure. Experimental chemists used chemical reactions. Structural chemists, such as Hodgkin, used crystallography. Despite daunting calculations, Hodgkin and her students at Oxford completed the structure in 1949, beating the experimental chemists and establishing x-ray crystallography as an indispensable tool in biochemistry. Even as Hodgkin was finishing her analysis of penicillin, however, she had already begun a study of B12, widely used to treat pernicious anemia. In 1957, she published the structure of this 180-atom molecule.   (A) [■] When she was awarded the Nobel Prize in 1964, she told a group of students at the ceremonies in Stockholm, Sweden, that she hoped her position as the only woman to receive the prize that year "will not be so very uncommon in the future, as more and more women carry out research in the same way as men".   
(B) [■] But what was perhaps Hodgkin’s greatest success came after the Nobel Prize, when she tackled the biggest molecule of her career. Insulin, a protein that regulates the body’s sugar storage, contains over 1000 atoms.
(C) [■] A deficiency in or insensitivity to insulin causes diabetes, a complex disease that causes suffering in several hundred million people worldwide. Hodgkin solved the structure of insulin in only five years.  
(D) [■] Her achievement proved that proteins have regular shapes, and it spawned research that ultimately led to effective treatments for diabetes.
An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.   Dorothy Crowfoot Hodgkin led a fruitful life and her success can be attributed to overcoming numerous hardships combined with her natural talents
Answer Choices
A. Unlike other children, she led a childhood which was full of opportunities to do chemistry experiments.   
B. Her studies at Oxford and Cambridge university laid a solid foundation for her great achievements later in life.   
C. After college, she carried on with more challenging research at Oxford university.   
D. In the 1950s and 1960s, she discovered the structures of penicillin and insulin, which were the greatest achievements in her life.   
E. In 1937, she received her doctorate and married Thomas Hodgkin.   
F. A past event with an old friend contributed to her future life in chemistry to some degree.
选项
答案A. Unlike other children, she led a childhood which was full of opportunities to do chemistry experiments. B. Her studies at Oxford and Cambridge university laid a solid foundation for her great achievements later in life. D. In the 1950s and 1960s, she discovered the structures of penicillin and insulin, which were the greatest achievements in her life.
解析 本题是篇章总结题，考查考生对全文段落大意的总体把握能力。全文讲的是Hodgkin进行科学研究的一生，选项A概括了她童年对科学的兴趣，选项B讲述了她科学研究的两个重要时期，即在牛津和剑桥大学，选项D是对她一生中两个最重要发现的总结。所以选了以上三项作为对全文的总结。而另外三个句子，有的不符合原文内容，有的并非阐述文章的中心思想。
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