GRE阅读机经练习分享 GRE报名

　　下面小编跟大家一起了解GRE阅读机经练习分享，希望对大家的学习有所帮助。
　　Larvae of many marine invertebrate species delay their metamorphosis into juveniles when cues signaling an appropriate juvenile environment are absent, thereby increasing their likelihood of thriving as juveniles and of ultimately reaching adulthood. Nevertheless, delayed metamorphosis has potential costs for juveniles, including reduced growth and increased mortality. Nearly all evidence of such costs involves species whose larvae do not feed but rather subsist on stored nutrients, indicating that insufficient energy reserves may be an underlying cause of these costs. Supporting this hypothesis are laboratory studies showing that in a certain bryozoan, the prolonged larval swimming that results from delayed metamorphosis is associated with size reductions in the juvenile feeding organ (the lophophore) and that one factor influencing the size of juveniles of certain barnacle species is how long larvae delay metamorphosis. However, other studies show that while significantly fewer juvenile Capitella worms survived to adulthood when metamorphosis had been delayed, prolonged larval swimming had no significant effect on juvenile size, suggesting, perhaps, that in some species, factors other than insufficient energy reserves account for the negative effects of the larval stresses that result from delayed metamorphosis.
　　1. The passage suggests that the “bryozoan,” the “barnacle species,” and “Capitella worms” all share which of the following characteristics?
　　A. The larvae of these species do not feed but rather subsist on stored nutrients.
　　B. The larvae of these species are unable to undergo metamorphosis if larval swimming is significantly prolonged.
　　C. The larvae of these species do not have enough energy to meet their needs when metamorphosis is delayed.
　　D. The juveniles of these species manifest the negative effects of delayed metamorphosis as a decrease in size.
　　E. The juveniles of these species are not significantly larger than their respective larvae.
　　推断题
　　解析：文章里面讨论的所有虫都是会靠之前储存的能量维持生活，而且对应到文章这一句话“Nearly all evidence of such costs involves species whose larvae do not feed but rather subsist on stored nutrients, indicating that insufficient energy reserves may be an underlying cause of these costs.” B选项无中生有。C选项也是无中生有。D选项不是一定会减少尺寸，however后面有转折。E选项也是无中生有。
　　2. The “hypothesis” implies that compared to marine invertebrate larvae that subsist on stored nutrients, marine invertebrate larvae that feed are less likely to
　　A. exhibit prolonged larval swimming as a result of delayed metamorphosis.
　　B. experience negative effects as a result of delayed metamorphosis.
　　C. thrive as juveniles in environments inappropriate for juveniles.
　　D. delay metamorphosis in the absence of appropriate environmental cues.
　　E. delay metamorphosis for an extended period of time.

　　推断题
　　解析：假设的内容是，Nearly all evidence of such costs involves species whose larvae do not feed but rather subsist on stored nutrients, indicating that insufficient energy reserves may be an underlying cause of these costs. 所以如果feed的幼虫就更不太可能遇到这种负面的结果。所以答案选B。
　　3. The passage is primarily concerned with
　　A. weighing the relative benefits and costs of delayed metamorphosis.
　　B. illustrating the range of costs that can result from delayed metamorphosis.
　　C. speculating on why the costs of delayed metamorphosis have gone unrecognized.
　　D. discussing a possible explanation of the costs of delayed metamorphosis.
　　E. debunking the notion that the costs of delayed metamorphosis are negligible.
　　文章目的题
　　解析：这篇文章都是在解释delayed metamorphosis costs的原因，就是想告诉我们为什么delayed metamorphosis会产生哪些不好的costs，所以答案选D。