GWD-23-Q14,题都没读懂

zcool

支持17楼

Mandyvic

一条新思路：完全可以把题目理解为-
A棉花和B棉花，A遭破坏，是虫太多导致的。对此加强-B也遭破坏；对此削弱-B没破坏。所以判断依据为B是否遭破坏。
这题完全和GWD-3-Q38异曲同工：-warbler鸣鸟数量下降，是因为咖啡田少了还是它吃的虫子少了。正确A项中Bo鸟不吃虫但数量也下降了。
可按是否吃虫把鸟分成A鸟(warbler)和B鸟(Bo)。
Kate:  The recent decline in numbers of the Tennessee warbler, a North American songbird that migrates each fall to coffee plantations in South America, is due to the elimination of the dense tree cover that formerly was a feature of most South American coffee plantations.



Scott:  The population of the spruce budworm, the warbler’s favorite prey in North America, has been dropping.  This is a more likely explanation of the warbler’s decline.



Which of the following, if true, most seriously calls Scott’s hypothesis into question?

The numbers of the Baltimore oriole, a songbird that does not eat budworms but is as dependent on South American coffee plantations as is the Tennessee warbler, are declining.
The spruce-budworm population has dropped because of a disease that can infect budworms but not Tennessee warblers.
The drop in the population of the spruce budworm is expected to be only temporary.
Many Tennessee warbler have begun migrating in the fall to places other than traditional coffee plantations.

Although many North American songbirds have declined in numbers, no other species has experienced as great a decline as has the Tennessee warbler.
其实棉花是否有抗体只是将棉花分类而已！

-- by 会员 carolinelmf (2007/11/1 20:46:00)

agree!!

阳光小捷子

GWD-23-Q14 Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year.This year the plantings（指cotton） are being seriously damaged by bollworms.Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide.Bollworms breed on corn, and last year more corn than usual was planted throughout cotton-growing regions.So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would be most useful to establish?

B.Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year（因为B虫没有对转基因过的cotton的杀虫剂产生抗药性，所以如果那些没经过转基因的cotton也遭受了不寻常的虫害，则支持结论：是因为B虫太多了，一直它除了吃corn，还要吃cotton；但他们如果没有遭受虫害，则经过转基因的cotton就更不可能会遭虫害了，一定是除了B虫之外的原因造成的）

B.Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year（因为B虫没有对转基因过的cotton的杀虫剂产生抗药性，所以如果那些没经过转基因的cotton也遭受了不寻常的虫害，则支持结论：是因为B虫太多了，一直它除了吃corn，还要吃cotton；但他们如果没有遭受虫害，则经过转基因的cotton就更不可能会遭虫害了，一定是除了B虫之外的原因造成的）

mastlight

支持17楼！！

kjia0120

up

viking00x

好像有点明白了，
如果B选项答案是肯定，也就是说没转基因的也遭受巨大损失，那至少说明转基因遭到巨大损失可能是虫子太多的原因（弱加强结论）
而如果B选项答案是否定，也就是说没转基因的没遭受损失（因为文章已经给出前提：虫子并没有抗药，因此如果是虫子太多的原因，吃转基因会死很多，因此更会去吃没转基因的，那么没转基因的应该相比转基因的遭受更大的损失，但此处如果没转基因的反而没遭到损失），那说明一定不是虫子太多的原因（削弱结论）

xdai555

那虫只吃玉米 那棉花还改造个毛抗虫  。。。

xdai555

其实跟杀虫剂没关系啊 我怎么觉得选B 就是为了证明 虫多虫少。。
虫多： 没转基因（没有杀虫剂的）棉花 被吃掉。
虫少：                                            没被吃掉。。

都没有提到装基因的棉花 会不会被吃掉 。。。 其实这个跟杀虫剂有什么关系！！！

而且这虫喜欢吃玉米啊。。 - -  为了证明虫多-->玉米不够吃 还要吃棉花。。  = =

soulwangh

xdai555 发表于 2013-2-22 16:12
其实跟杀虫剂没关系啊 我怎么觉得选B 就是为了证明 虫多虫少。。 虫多： 没转基因（没有杀虫剂的）棉花 被 ...

Yes, the conclusion has nothing to do with the pesticide. Because, in the premise, the pesticide has already been ruled out as a possibility to cause the damage of cotton.

ssn_wonder

I think we should focus on " unusually" on OA B. If yes, that means normal cotton was suffered more by BW this year. That tells us there are more BW this year than before, supporting the conclusion that BW from corn affects cotton.
If no, that means, the number of BW is not increasing. However cotton was suffered more by BW this year. It might be that BW develop resistance to cotton's insecticide.