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  3. Passage 1 Lonely people, it seems, are at greater risk than the gregarious o...

Passage 1 Lonely people, it seems, are at greater risk than the gregarious o...

admin2020-12-24  22
问题 Passage 1
Lonely people, it seems, are at greater risk than the gregarious of developing illnessesassociated with chronic inflammation, such as heart disease and certain cancers. A paper publishedlast year in the Public Library of Science, Medicine, shows the effect on mortality of loneliness iscomparable with that of smoking and drinking after examining the results of 148 previous studiesand controlled for factors such as age and pre-existing illness.
Steven Cole of the University of California, Los Angeles, thinks he may know why this is so.
He told the American Association for the Advancement of Science meeting in Washington, D.C.,about his work studying the expression of genes in lonely people. Dr. Cole harvested samples ofwhite blood cells from both lonely and gregarious people. He then analysed the activity of theirgenes, as measured by the production of a substance called messenger RNA. This molecule carriesinstructions from the genes telling a cell which proteins to make. The level of messenger RNA frommost genes was the same in both types of people. There were several dozen genes, however, thatwere less active in the lonely, and several dozen others that were more active. Moreover, both theless active and the more active gene types came from a small number of functional groups.
Broadly speaking, the genes less active in the lonely were those involved in staving off viralinfections. Those that were more active were involved in protecting against bacteria. Dr. Colesuspects this could help explain not only why the lonely are iller, but how, in evolutionary terms, thisodd state of affairs has come about.
The crucial bit of the puzzle is that viruses have to be caught from another infected individualand they are usually species-specific. Bacteria, in contrast, often just lurk in the environment, andmay thrive on many hosts. The gregarious are therefore at greater risk than the lonely of catchingviruses, and Dr. Cole thus suggests that past evolution has created a mechanism which causes whitecells to respond appropriately. Conversely, the lonely are better off ramping up their protection
against bacterial infection, which is a bigger relative risk to them.
What Dr. Cole seems to have revealed, then, is a mechanism by which social environmentreaches inside a person′ s body and tweaks its genome so that it responds appropriately. It is not thatthe lonely and the gregarious are genetically different from each other. Rather, their genes areregulated differently, according to how sociable an individual is. Dr. Cole thinks this regulation ispart of a wider mechanism that tunes individuals to the circumstances they find themselves in.
What message does Dr. Cole seem to convey by the mechanism
选项 A.The lonely people differ in genes from the gregarious people.

B.Sociability can adjust a person' s genome and make it work properly,

C.The lonely people can become sociable if they regulate their genes.

D.Individuals have to find their own ways to adapt to the environment.
答案B
解析推断题。根据题干信息定位到最后一段。由本段前三句可知，Cole博士似乎已经揭示出这样一种机制，社交环境可以影响人们体内的生化活动，调整人体内的基因组以让其做出恰当的反应。这并非说孤独的人和爱交际的人在基因上有所不同．而是根据交际程度的不同．这两种人以不同的方式调控各自的基因。归纳上述内容可推断，交际程度能调整人的基因组，使它得以良好运作。故B项为正确答案。A项与此意矛盾。可排除。C项在原文中并未提及。D项“个人要找到他们自己的方式来适应环境”不符合Cole博士要表达的意思。
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