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Narrator Listen to a lecture in a music class. Now get ready to answer the questions. You may use your notes to help you answer. Which of the following is NOT the goal of the course
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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. The word demanded in Paragraph 5 is closest in meaning to______.
Narrator Listen to a talk between two students. Now get ready to answer the questions. You may use your notes to help you answer. What does Student B mean when he says this
Narrator Listen to a talk between two students. Now get ready to answer the questions. You may use your notes to help you answer. What does Student B imply when he says this
Whose Grave Is This Anyway There are many legends about the world famous Egyptian Pharaohs’ tombs, which have lain silent for thousands of years along the Nero River. In reality though, this silence has constantly been disturbed by a great variety of people. While considering their different motivations in doing so, we must examine whether disturbing the ancient tombs is justifiable or worthy of condemnation. A. [■] When Howard Carter and his party opened the tomb of the Egyptian king Tutankhamen in 1922, there was rejoicing around the world. B. [■] The tomb was largely intact and not seriously pillaged by ancient grave robbers, so it still contained the wonderful artifacts that had been buried with the young king more than three millennia earlier. C. [■] Over the next several years Carter and his team systematically photographed and catalogued the objects from the tomb, then transported them to the Cairo Museum.D. [■] There is a certain irony in this story that raises complex ethical questions. Why are Carter and his party not called grave robbers Why are their actions in stripping the tomb acceptable—even praiseworthy—when similar behavior by common thieves would be deplored No matter who opens a tomb and takes away its contents, that person is violating the intentions of those who sealed the tomb originally. No matter what the motivation, a human body that was meant to rest in peace for all time has been disturbed. Should this not make us feel uncomfortable From the beginning, some were uneasy about the propriety of unearthing Tutankhamen’s remains. When Lord Carnarvon, Carter’s sponsor, died suddenly from a mosquito bite, and several others connected with the project experienced tragedies, rumors arose about the "curse of King Tut". But Carter himself died peacefully many years later, and the talk subsided. Perhaps it is the passage of time that transforms grave robbing into archaeology. Carter would no doubt have been outraged if, say, his grandmother’s coffin had been dug up to strip the body of its jewelry. But after three thousand years Tutankhamen has no living relatives to protest his disturbance. Perhaps it is a question of the words we use to describe such ancient finds. We speak of Tutankhamen’s "mummy", and mummy is a clean, historical-sounding word. Parents bring their children to museums to see the mummies and mummy cases. We can almost forget that a mummy is the embalmed body of a dead human being, pulled out of its coffin so that we can marvel at the coffin and sometimes the body itself. Or, perhaps the difference between grave robbing and archaeology lies in the motives of the perpetrators. Common thieves are motivated by greed, by their quest for money to be made by selling stolen objects. Carter and his team did not sell the treasures from Tutankhamen’s tomb but stored them safely in the Cairo Museum, where art lovers from around the world can see them. They were, in effect, making a glorious gift to the people of our century and centuries to come (while at the same time, one must point out, acquiring significant glory for themselves). The basic issue is a clash of cultural values. To the Egyptians, it was normal and correct to bury their finest artworks with the exalted dead. To us, the idea of all that beauty being locked away in the dark forever seems an appalling waste. We want to bring it into the light, to have it as part of our precious artistic heritage. Almost no one, having seen these magnificent treasures, would seriously propose they be put back in the tomb and sealed up. In the end, inevitably, our cultural values will prevail simply because we are still here and the ancient Egyptians are not. After three thousand years, Tutankhamen’s grave really isn’t his anymore. Whether right or wrong, it belongs to us. According to Paragraph 7, what is the contribution of Carter and his party
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