题干

探究重力和单侧光对生长素分布的影响程度,实验操作:如图所示(注:A盒下侧有开口,可以进光)结果预测及结论如下:

①若A、B中幼苗都向上弯曲生长,只是B向上弯曲程度大,说明重力对生长素分布的影响大于单侧光对生长素分布的影响.

②若A中幼苗向下弯曲生长,B中幼苗向上弯曲生长,说明单侧光对生长素分布的影响大于重力对生长素分布的影响.

③若A中幼苗水平生长,B中幼苗向上弯曲生长,说明单侧光对生长素分布的影响与重力对生长素分布的影响相等.

④若A、B中幼苗都向上弯曲生长,只是B向上弯曲程度大,说明重力对生长素分布的影响小于单侧光对生长素分布的影响.

结果预测及结论错误有几项( )

A:1

B:2

C:3

D:4

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答案(点此获取答案解析)

B

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    Whether you live in Seattle or the Sahara desert, the time has come to invest in a good raincoat or umbrella, a new study suggests.

    As global temperatures continue to rise, more “extreme rain” events—intense, cats-and-dogs down pours—can be expected, said the study, published Monday in the journal Nature Climate Change. And that, scientists said, means an increased flood risk, particularly for the world's driest areas. The study challenges the idea that global warming is causing dry areas to become drier and wet areas wetter.

    “In both wet and dry regions, we see these great increases in heavy precipitation(冰雹),” lead author Markus Donat, a climate scientist at the University of New South Wales, told Nature.

    Donat and his team collected data from 1951 to 2010 on extreme precipitation events from 11, 000 weather stations around the world, Nature reported.

     In that time, the number of days with“extreme precipitation” increased 1 percent to 2 percent per decade.

  “We found a strong relationship between global warming and an increase in rainfall, particularly in areas outside of the tropics,” Donat said in a statement.

  “Importantly, this research suggests we will see these extreme rainfall events increases at regional levels in dry areas, not just as an average across the globe,” Donat added.

    Peter Stott, a senior climate scientistat Met Office, told Climate Central that the study's findings are important, because more violent rainfall and flooding will “challenge our capability toadapt to a rapidly changing climate.”

    As Nature reported, the researchaligns(结盟)with a 2015 study that found global warming has led to a sharp increase in record-breaking precipitation events. Donat told Nature that his study should come as a warning to world governments.