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  3. Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten

Dorothy Crowfoot Hodgkin When Dorothy Crowfoot Hodgkin was ten

游客2024-01-04  10
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. [br] In Paragraph 2, why does the author mention a jungle gym?
选项 A、To show that chemistry elements take the shape of a jungle sometimes.
B、To indicate that there are many differences between chemistry and other fields.
C、To demonstrate that studying chemistry is very hard due to its indirectness and uncontrollability.
D、To indicate that it is very difficult to determine the arrangement of the atoms in a crystal.
答案 C
解析 本题为事实信息题，主要考查考生是否具备排除干扰项并抓住文章中所阐明的事实与信息的能力。题目问：在第二段，作者为什么要提到儿童攀缘游戏立体构架?这一句用了一个比喻，将“决定晶体中原子的排列”比作“根据儿童攀缘游戏立体构架的影子来决定其形状”。这说明，决定晶体中原子的排列是非常不容易的，所以选C项。
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