【正文】 graphic roots .Most tests require collecting cells by webbing saliva in the mouth and sending it to the pany for testing. All tests require a potential candidate with whom to pare DNA. But some observers are skeptical, “There is a kind of false precision being hawked by people claiming they are doing ancestry testing,” says Trey Duster, a New York University sociologist. He notes that each individual has many ancestorsnumbering in the hundreds just a few centuries back. Yet most ancestry testing only considers a single lineage, either the Y chromosome inherited through men in a father’s line or mitochondrial DNA, which a passed down only from mothers. This DNA can reveal genetic information about only one or two ancestors, even though, for example, just three generations back people also have six other greatgrandparents or, four generations back, 14 other greatgreatgrandparents. Critics also argue that mercial genetic testing is only as good as the reference collections to which a sample is pared. Databases used by some panies don’t rely on data collected systematically but rather lump together information from different research projects. This means that a DNA database may differ depending on the pany that processes the results. In addition, the puter programs a pany uses to estimate relationships may be patented and not subject to peer review or outside evaluation. paragraphs 1 and 2 , the text shows PTK’s ___________.[A]easy availability[B]flexibility in pricing [C] successful promotion [D] popularity with households27. PTK is used to __________.[A]locate one’s birth place[B]promote genetic research[C] identify parentchild kinship [D] choose children for adoption 28. Skeptical observers believe that ancestry testing fails to__________.[A]trace distant ancestors [B] rebuild reliable bloodlines[C] fully use genetic information [D] achieve the claimed accuracy 29. In the last paragraph ,a problem mercial genetic testing faces is __________.[A]disorganized data collection [B] overlapping database building 30. An appropriate title for the text is most likely to be__________.[A]Fors and Againsts of DNA testing [B] DNA testing and It’s problems[C]DNA testing outside the lab [D] lies behind DNA testing Text 3The relationship between formal education and economic growth in poor countries is widely misunderstood by economists and politicians alike progress in both area is undoubtedly necessary for the social, political and intellectual development of these and all other societies。2009年全國碩士研究生入學統(tǒng)一考試英語試題Part AText1Habits are a funny thing. We reach for them mindlessly, setting our brains on autopilot and relaxing into the unconscious fort of familiar routine. “Not choice, but habit rules the unreflecting herd,” William Wordsworth said in the 19th century. In the everchanging 21st century, even the word “habit” carries a negative connotation.So it seems antithetical to talk about habits in the same context as creativity and innovation. But brain researchers have discovered that when we consciously develop new habits, we create parallel synaptic paths, and even entirely new brain cells, that can jump our trains of thought onto new, innovative tracks. But don’t bother trying to kill off old habits。 once those ruts of procedure are worn into the hippocampus, they’re there to stay. Instead, the new habits we deliberately ingrain into ourselves create pa