OG12 CR59 急求高人解答~

shjoiy325

59.   In order to withstand tidal currents,juvenile horseshoe crabs frequently burrow in the sand. Such burrowing discourages barnacles from clinging to their shells. When fully grown, however,the crabs can readily withstand tidal currents without burrowing, and thus they aquire substantial populations of barnacles. Surprisingly,in areas where tidal currents are very weak,juvenile horseshoe crabs are found not to have significant barnacle populations, even though they seldom burrow.

A. Tidal currents do not themselves dislodge barnacles from the shells of horseshoe crabs.

B. Barnacles most readily attach themselves to horseshoe crabs in aeras where tidal currents are weakest.

C. The strength of the tidal currents in a given location varies widely over the course of a day.

D. A very large barnacle population can significantly decrease the ability of a horseshoe crab to find food.

E. Until they are fully grown,horseshoe crabs shed sheir shells and grow new several times a year.

答案是 E。答案我觉得和原文的关系不大啊。我不是很理解文章内容和选项。


请各位大牛帮我解释下原文和选项吧~拜托了~

醒醒Shine

再次感叹下数学真的是门好学问。一切现象都能抽丝剥茧用数学的思维来理清。

醒醒Shine

我理了理思路，清晰多了：
关于选项D
无关：非常有诱惑力的选项。但是再仔细看题目的区别，1说的是幼年crabs站不住潮汐只有成年以后才会需要更多的barnacles。2却说的是尽管没有潮汐影响了，幼年crabs还是没有需要更多的barnacles。Why？D的问题是没有对幼年和成年期的区别加以弥补gap，理应排除。

正确选项E：
使两者不矛盾：原本1说了不怕潮汐的成年crabs会需要更多的barnacles，2却排除了潮汐对crabs就会增加barnacles的影响，想要既不否定1，也能解释2，就要这么说：他们成年后确实是需要更多的barnacles，但是在需要的过程中，小小crabs自己还在不断脱壳，所以看上去并没有增加barnacles的量。——类比：在y=ax+b里，原本我们以为x是唯一的变量，所以x增加，y增加。现在b也在同时减少，所以导致我们看到y没有发生大幅的增加了。

MissUindeed

这题第一次我也错了，后来正确答案就记住了，不能保证这题目如果直接考试我能做对

美人夜带刀

哈哈我和你一样。。。

篮子里的幸福

此题的关键在于juvenile(少年的），之前我不认识这个单词，还以为是螃蟹的一个种类呢……

aigojackie

请问这题的A选项怎么解释呢？

jxgzcly

谢谢上面解释，
但是又有疑问，根据E的说法，那些fully grown的horseshoe crabs 的壳不是一样会 have significant barnacle populations吗？

-- by 会员 yuanxiaoning (2011/8/26 15:52:18)

When fully grown, however,the crabs can readily withstand tidal currents without burrowing, and thus they aquire substantial populations of barnacles.
E. Until they are fully grown,horseshoe crabs shed sheir shells and grow new several times a year.

朕乃橙子

我也是跑来想问这题 觉得没什么联系=。=结果看见有人在问~上边高人好严密 果然应该注意一些形容词的描述

yuanxiaoning

谢谢上面解释，
但是又有疑问，根据E的说法，那些fully grown的horseshoe crabs 的壳不是一样会 have significant barnacle populations吗？