请问是这道GWD原题么?谢谢 GWD28-19 Plankton 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. -- by 会员 jenny1989 (2009/11/29 10:06:25)
这题不是我考的那道。但是不能说就不是啊。这题寂静里面有啊。答案我都知道是D。
我考的那道一来就讲海藻光合作用photosynthesis怎么样怎么样。然后海边的怎么了,不是海边的怎么了,做了一个实验什么的。
后来的真的不记得了。因为好长,这题题目超长。 |