gwd 28-19,还没有讨论过,欢迎指教

hy903

28-19: Plankton generally thrive in areas of the ocean with sufficient concentrations of certain nitrogen compounds near the surface where plankton live. Nevertheless, some areas, though rich in these nitrogen compounds, have few plankton. These areas have particularly low concentrations of iron, and oceanographers hypothesize that this shortage of iron prevents plankton from thriving. However, an experimental release of iron compounds into one such area failed to produce a thriving plankton population, even though local iron concentrations increased immediately.

Which of the following, if true, argues most strongly against concluding, on the basis of the information above, that the oceanographers’ hypothesis is false?

A: Not all of the nitrogen compounds that are sometimes found in relatively high concentrations in the oceans are nutrients for plankton.

B: Certain areas of the ocean support an abundance of plankton despite having particularly low concentrations of iron.

C: The release of the iron compounds did not increase the supply of nitrogen compounds in the area.

D: A few days after the iron compounds were released, ocean currents displaced the iron-rich water from the surface.

E: The iron compounds released into the area occur naturally in areas of the ocean where plankton thrive.

好象不少人选d,可是我不太明白d的意思。

我选了a, 如果说实验中nitrogen 和plankton 所需要的不一样的话，即使iron量

够了，也没有办法令plankton thrive。

请指教！

laihong

选D,因为oceanographers’ hypothesis 的理由是low concentrations of iron, 所以D说现在的concentrations of iron低

hy903

还是不太明白哦。gg能不能在解释的详细些。

leiby1019

argues most strongly against concluding, on the basis of the information above, that the oceanographers’ hypothesis is false?

我觉得这道题重点在读问题上：反对一个结论，这个结论是海洋学家的假设是错误的。

换句话说，支持海洋学家的假设。

mm根据我说的这些在理解一下 D就是答案。

chelsea710

要对结论反对，就要找到个合适的理由来解释为什么人为的释放了iron,还是会导致failed to produce a thriving plankton population。

而D 就合理的解释了这个问题，因为Plankton生活在表面上，而表面上的iron被冲走了。。。。

我解释到头了。就这水平

steveyangxt

讨论过了 mm找找看

hedge

thanks

hedge

 没明白,牛人讲讲

jimoshanlin

我的理解

原文：海洋学家的结论是iron的密度太低导致P不能生长。但原文结论说海洋学家错误，然后举出例子说投入了大量的iron，P还是不能生长。

问题：哪个理由会反对原文的结论，反对海洋学家错误，即支持海洋学家的结论？那就需要解释为什么通过这个实验，iron的密度还是很低，因为海水冲走了大量的iron！

这个题目，读懂问题很关键。另外，不知道大家有没有注意到原文的immediately。选项D正好是针对immediately做出解释，立即增加的iron密度，不能保证iron的高密度就可以维持，实验不能有效反驳海洋学家的结论。。。。。

jintian

up