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  3. A few milliamps of electricity can cause plants to increase synthesis of chemicals. These compounds often also have a pharmacolo

A few milliamps of electricity can cause plants to increase synthesis of chemicals. These compounds often also have a pharmacolo

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问题     A few milliamps of electricity can cause plants to increase synthesis of chemicals. These compounds often also have a pharmacological (related to medicine) or commercial value, so the trick could be used to help increase yields of commercially useful biologicals. Artemisinic acid, from sweet wormwood, for example, is used in malarial medications, and shikonin (紫草素), from the purple gromwell plant, is used against skin infections.
    Researchers have long known that stressing plants can force them to take defensive action, often ramping up the production of protective chemicals that, for example, make them more resistant to insect attack. It has become common practice to stress such plants into increasing their yields. This is usually clone using physical stress elicitors (诱导子), including bits of the micro-organisms that normally attack the plants, or irritants made from metallic compounds such as copper chloride. These are effective, but they come at a cost. Most elicitors are toxic to plants and can build up in tissues, making it necessary to occasionally "clean" a plant of the chemicals so they keep having the same effect.
    Recently, research groups at the University of Arizona in Tucson found that the application of an electric current to the hairy roots of the poisonous herb Hyoscyamus muticus stimulated the production of the herb’s toxin hyoscyamine (天仙子胺). This unpublished finding inspired Hans Van Etten, also of the University of Arizona, and his colleagues to test sub-lethal levels of electrical currents on other plants, to assess electricity’s potential to elevate chemical production.
    The researchers exposed eight different plant species (ranging from Japanese pagoda tree seedlings to pea plants) to weak electrical currents of 30 milliamps. Seven of the plants increased their production o{ defensive chemicals. The average boost of chemical production was 20 times, they report in Biotechnology Progress. One plant, a type of alfalfa, increased its chemical yield by 168 times. These values are very similar to those achieved using chemical elicitors, and seem to have no lethal effects-just a negative effect on growth. The treatment can be used over and over again without the build-up of any unwanted material.
    The useful compounds would be very easy to harvest: they simply pour out into solution if the plants are grown hydroponically. "The fact that we can use electricity instead of toxic materials to elicit chemical production is very exciting because it means we get to look at how these chemicals form without having to constantly add and remove toxins from the system," says Van Etten. "This is a really novel and creative approach that I’ve never seen before," says plant metabolic engineer Fabricio Medina Bolivar from Arkansas State University in Jonesboro. "The possibilities for using electricity with plants in this way are absolutely tremendous. "
The views of Fabricio and Van Etten towards the way of using electricity to elicit chemical production are ______.
选项 A、different
B、opposite
C、similar
D、complementary
答案C
解析 通过分析题干可知，本题需要了解Fabricio和Van Etten的观点，然后进行比较。最后一段分别阐述了两人的观点，第二句指出Van Etten说“我们使用电力而不是有毒的材料来诱发化合物生产的事实很振奋人心。”第三句指出Fabricio Medina Bolivar的观点是“这真是一种既新奇又有创意的方法”，可见两人对使用电力来诱导化学物的产生都持正面观点，因此两人的态度是相似的，故[C]正确。  
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