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Sugar Power for Cell Phones Using enzymes commonly found in living cells，a new type of fuel cell produces small amounts of electricity from sugar.If the technology is able to succeed in mass production，you may some day share your sweet drinks with your cell phone. When researchers previously used enzymes in fuel cells，they had trouble keeping them active，says Shelley D.Minteer of St Louis University1.Whereas biological cells continually produce fresh enzymes，theres no mechanism in fuel cells to replace enzymes as they quickly degrade. In the new fuel Cell，tiny polymer bags of enzyme are embedded in a membrane that coats one of the electrodes.When glucose from a sugary liquid gets into a pocket，the enzyme oxidizes it，releasing electrons and protons.The electrons cross the membrane and enter a wire through which they travel to the other electrode，where they react with.oxygen in the atmosphere to produce water.The flow of electrons through the wire constitutes an electrical current that can generate power. Sugar-eating fuel cells could be an efficient way to make electricity.Sugar is easy to find. And the new fuel cells that run on it are biodegradable，so the technology wouldnt hurt the environment.The scientists are now trying to use different enzymes that will get more power from sugar.They predict that popular products may be using the new technology in as little as 3 years. 1. According to the first paragraph，when can we share our sweet drinks with our cell phones? B When the technology of producing a new type of fuel cell appears. D When the technology of mass producing cell phones appears. A They had trouble keeping enzymes in fuel cells active. C They had trouble producing fresh enzymes. 3. According to Paragraph 5，electrons are released B when glucose from a sugary liquid goes through the enzyme. D when the enzyme oxidizes the sugary liquid that goes through a pocket. A Their limitless power generation capacity is amazing. C Their limited power generation capacity is the result of great efforts. 5. According to the last paragraph，what is NOT true of the new fuel cells? B The new fuel cells are environment friendly. D It will take some time before the new fuel cells can be used in popular products. 1. C A和D明显不是正确答案。B不是正确选择，因为只有当这种新的燃料电池被大规模生产时，才有可能实现用甜饮料给手机提供电能。 3. C 该段第二句When glucose from a sugary liquid penetrates a pocket，the enzyme oxidizes it，releasing electrons and proton中的it指代glucose，而不是a sugary liquid，因 此C是正确选择。 5. D 文章的最后一段指出了这种新型燃料电池的优点，即A、B、C所述内容。最后一句说，科学家预计，在不到三年的时间里这种新技术便可在大众的流行产品中使用。所以D是正确选择。 | 
