题干

2013年6月20日上午10时,中国载人航天史上的首堂太空授课开讲.神舟十号女航天员王亚平在天宫一号开展基础物理实验,为全国青少年进行太空授课.很多同学对太空中的特殊环境提出了猜想,让我们一起来分享一下:太空中,在湿润的软质土壤横放一株植物幼苗.让它在完全失重的状态下,置于单侧光照射的环境中培养若干天.其根茎的生长方向应该是____ .

A.根向下生长,茎向上生长
B.根、茎都向原来摆放的方向生长
C.根向土壤方向生长,茎向光源方向生长
D.根和茎都向水平方向生长.
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C

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Wilderness

    “In wilderness(荒野) is the preservation of the world.” This is a famous saying from a writer regarded as one of the fathers of environmentalism. The frequency with which it is borrowed mirrors a heated debate on environmental protection: whether to place wilderness at the heart of what is to be preserved.  

     As John Sauven of Greenpeace UK points out, there is a strong appeal in images of the wild, the untouched; more than anything else, they speak of the nature that many people value most dearly. The urge to leave the subject of such images untouched is strong, and the danger exploitation(开发) brings to such landscapes(景观) is real. Some of these wildernesses also perform functions that humans need—the rainforests, for example, store carbon in vast quantities. To Mr.Sauven, these ”ecosystem services” far outweigh the gains from exploitation.

    Lee Lane, a visiting fellow at the Hudson Institute, takes the opposing view. He acknowledges that wildernesses do provide useful services, such as water conservation. But that is not, he argues, a reason to avoid all human presence, or indeed commercial and industrial exploitation. There are ever more people on the Earth, and they reasonably and rightfully want to have better lives, rather than merely struggle for survival. While the ways of using resources have improved, there is still a growing need for raw materials, and some wildernesses contain them in abundance. If they can be tapped without reducing the services those wildernesses provide, the argument goes, there is no further reason not to do so. Being untouched is not, in itself, a characteristic worth valuing above all others.

    I look forwards to seeing these views taken further, and to their being challenged by the other participants. One challenge that suggests itself to me is that both cases need to take on the question of spiritual value a little more directly. And there is a practical question as to whether wildernesses can be exploited without harm.

    This is a topic that calls for not only free expression of feelings, but also the guidance of reason. What position wilderness should enjoy in the preservation of the world obviously deserves much more serious thinking.