大家帮忙做做这个英语阅读理解，谢谢

Question

How does the nose manage the sophisticated discrimination? Lack of evidence hasn't kept scientists from speculating(假设)．One idea is that every odor molecule vibrates at its own frequency，creating patterns of disturbance in the air similar to the wave patterns produced by sound．According to this theory，the nerves act as receivers for the unique vibrations of every odor molecule．The scheme (设想) requires no direct contact between the molecule and the nerve cell．
Another suggestion is that primary odors，equivalent to the primary colors of vision，underlie all smells and are detected by receptor sites on the olfactory (嗅觉的) nerves．Different combinations of about thirty basic smells，with labels such as malty，minty，and musky，could form an infinite number of odors．
Other scientists think that each smell is its own primary smell．They believe the olfactory nerve endings have specific receptor protein that bind to each of the chemicals people can sense．This theory，however，calls for thousands of different proteins--none of which has been found．
The science of smell is so empirical (经验主义的)，says Robert Gesteland, a neurobiologist at Northwestern University，“there’s no predictive base for experiments”．Unlike the senses of sight，touch，and hearing，olfaction studies have attracted only a small share of scientific interest．That may change．Researchers hope that unraveling (阐明) the mystery of smell will advance our understanding of the brain．Smell research promises to help physicians better diagnose the smell and taste disorders that affect two million Americans．And in the future，with enough known about smell, it might be possible to endow strange，unappealing hut nutritious foods with more familiar odors，perhaps expanding the world’s food supply．For the moment，however，what the nose knows it isn’t revealing．
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Answer 1

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