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?
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. 我不太理解D选项是怎么削弱oceanographers的假设是错误的?瞧这问题问得……太恶心了 麻烦大家帮忙理解下吧,谢谢了!
原文说an experimental release of iron compounds into one such area failed to produce a thriving plankton population, even though local iron concentrations increased immediately. 这个结论里有说道,立刻提升铁的含量,也没有让p的数量上升~题目是要weaken掉这个结论~也就是说要证明真正铁浓度的提高~是可以让p数量上升的~这里只有D说~在release一些铁后要过两天~才能达到一个铁浓度高的条件~~进而才能去验证到底是不是铁的浓度能让p的数量上升~~~
问题其实问的是加强,加强那个什么学家的假设。即hypothesize that this shortage of iron prevents plankton from thriving。然后题目中又给出加进去了iron还是没有效果,而D选项说洋流把表层的海水冲了,就说明题目提到的“添加的iron”其实不是没有作用,是因为洋流把他们冲走了,才没有作用。
原文说an experimental release of iron compounds into one such area failed to produce a thriving plankton population, even though local iron concentrations increased immediately. 这个结论里有说道,立刻提升铁的含量,也没有让p的数量上升~题目是要weaken掉这个结论~也就是说要证明真正铁浓度的提高~是可以让p数量上升的~这里只有D说~在release一些铁后要过两天~才能达到一个铁浓度高的条件~~进而才能去验证到底是不是铁的浓度能让p的数量上升~~~
-- by 会员 yydetiankong (2010/9/13 19:00:56)
其实题目问的是which could argue against the oceanographers hypothesize that this shortage of iron prevents plankton from thriving is wrong. 所以其实是加强oceanographers' hypothesize that this shortage of iron prevents plankton from thriving. 你所说的增加iron能偶增加P,这个结论是我们自己退出来的,不是题目问的结论