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额 麻烦个请问是这个不 -3-Q23. GWD-13-32 Macrophages are cells that play a role in the response of the immune system of mice and other mammals to invasive organisms such as bacteria. Unlike other mice, mice that are genetically incapable of making these particular cells do not show elevated levels of nitrates when infected with bacteria. The statements above, if true, provide the most support for which of the following conclusions? Mice that are unable either to make macrophages or to make them in sufficient numbers will protect themselves from bacterial infections in some other way. Mice that show elevated levels of nitrates can easily fight off most types of bacterial infections. In mice, macrophages play a role in the production of nitrates or inhibit a process by which nitrates are broken down or otherwise eliminated. When a healthy mouse becomes infected with an invasive organism, the number of macrophages in the mouse’s body decreases. Injections of nitrates into mice that lack macrophages will not enhance the ability of these animals’ immune systems to fight off infection. 答案为C 1。 关键在于理解UNLIKE,Unlike other mice, mice that are genetically incapable of making these particular cells do not show elevated levels of nitrates when infected with bacteria意思为:不能造M的老鼠感染细菌时硝酸盐没有显示升高。能造M的老鼠感染细菌时硝酸盐显示升高(UNLIKE)。C选项说出硝酸盐升高的两种方式,PRODUCTION和 INHIBIT。 2。其它易排除,A较混淆。A的问题在于sufficient。怎样才算sufficient,这概念太含糊,归纳题是不允许这种含糊概念的,再说对那些造M量不足的老鼠,不见得会用其它方式抵抗细菌,难道就不允许由于M细胞不够而生病或根本没事吗。其实我一眼就不喜欢A,它不象归纳题选项,好像跟原文关系不大。感觉上新信息太多,又是some other way,又是sufficient。
1。从单纯找答案角度,对原文的理解仅限于M细胞对老鼠的硝酸盐含量有影响便可以。只有C有这层意思 2。C的意思仅限于“对硝酸盐的产生有作用或抑制硝酸盐的减少”,起作用的结果是“维持或升高”(大概念)。也即有两种情况都可以:“维持”,“升高”。原文说的是“升高”的情况(小概念)。原文如果为小概念,那末选项为大概念必然对。比如:原文为leslie123456789GMAT考了800分(小概念),那末选项leslie123456789GMAT考了750分以上(大概念)必然对。 |
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