問題詳情

Questions 48-50: Read the following article from which three paragraphs have beenremoved. Choose the BEST paragraph from those in the box below for each gap in thearticle.
(A) In 1935, Hodgkin discovered that it was essential to keep the crystals wet with the “motherliquor” while X-raying them. If the liquid dries out, the molecules start to lose their orderedarrangement, and when hit with X-rays, they don’t give a clear pattern of spots.
(B) Hodgkin’s legacy is indeed multifaceted. She was not only an exceptional scientist but alsowas, and continues to be, an inspirational role model to generations of researchers in theUK and elsewhere, both male and, very importantly, female. Changes in our culture in thelast 10 or 15 years appear to have contributed to attention deficiency syndrome.
(C) Hodgkin became interested in chemistry and in crystals at about the age of 10, and thisinterest was encouraged by Dr. A.F. Joseph, a friend of her parents in the Sudan, who gaveher chemicals and helped her during her stay there to analyze ilmenite.
(D) Hodgkin’s work also had an enormous impact on the treatment of diabetes. In 1969, after35 years of enormously tenacious and brilliant work, she solved the 3D shape of the insulinmolecule. Insulin is an important hormone used by the body to process sugars in food, andunderstanding its structure has helped untangle the mechanism of its action, with criticalimplications for human diabetes control.
(E) Hodgkin is fondly remembered by her research students, who included many women. Shewas also involved in a wide range of peace and humanitarian causes and was especiallyconcerned about the welfare of scientists in the Soviet Union, China, and North Vietnam.  Dorothy Crowfoot Hodgkin may be the most famous British scientist of whom most people havenever heard. As such, she would be a very appropriate face for the new £50 note, on which the Bankof England wants to feature a picture of a scientist.Hodgkin was the foremost leader and innovator in her field, and the major impact of her workled to her becoming the only female British scientist to win a Nobel Prize (so far). The 1964 awardrecognized her work in chemistry using a technique known as X-ray crystallography to find out thethree-dimensional shapes of penicillin (1945) and vitamin B12 (1955).Accurate knowledge of the shape of penicillin was pivotal in understanding how it couldovercome bacterial infections. As a result, Hodgkin’s work is still important in the development ofnew antibiotics as some bacteria have developed resistance to existing drugs.48In addition to her accomplishment in diabetes treatment, key to Hodgkin’s work was thetechnique of X-ray crystallography, a way of working out how a complex molecule is arranged inthree dimensions. The way we find out this 3D shape is by growing tiny crystals of a substance sothat its molecules are all lined up in an orderly array. We then hit this array with X-rays and capturethe resulting “diffraction pattern” of spots that indicate how the molecules interfere with the beam.By capturing patterns from each side of the crystal and performing some mathematical computations,we can eventually get the average of the shapes of all the molecules, highlighting all the commonfeatures. This gives us a picture of the density of electrons in the molecule in 3D space and show howthe atoms of the molecule are arranged.49Hodgkin’s pioneering work in crystallography gave birth to a whole new field that applied themethods she developed to large biologically important molecules, including DNA and proteins. Wenow know the 3D shapes of over 139,000 biological molecules, and all the information is stored in acompletely open access database called the Protein Data Bank.50She was also very active in standing up for her core beliefs as a pacifist. For 12 years she waspresident of Pugwash, an organization founded in 1957 dedicated to reducing the danger of armedconflict and which sought peaceful solutions to global security threats. She even inspired her formerstudent Margaret Thatcher despite their differing politics.Her life was a shining example to many so it would be entirely appropriate for us to honor hergreat scientific achievements, and help give her the public recognition she deserves, by putting herimage on our new £50 notes.
48
(A)
(B)
(C)
(D)
(E)

參考答案

答案：D
難度：簡單0.7
統計：A(0),B(1),C(0),D(7),E(0)

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