题干

枪乌贼是一种生活在海洋中的软体动物,它有巨大的神经细胞,这种神经细胞能像红细胞一样,不断吸收K+.科学家用一种有毒物质使神经细胞中毒,吸收K+的功能就消失.如果注入一种物质,神经细胞又能恢复吸收K+的功能,一直到这种物质消耗完,请分析这种物质是什么(   )

A:淀粉

B:ATP

C:葡萄糖

D:麦芽糖

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B

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    A new generation addiction is quickly spreading all over the world. Weboholism, a twentieth century disease, affects people from different ages. They surf the net, use email and speak in chat rooms. They spend many hours on the computer, and it becomes a compulsive habit. They cannot stop, and it affects their lives.

    Ten years ago, no one thought that using computers could become compulsive behavior that could affect the social and physical life of computer users. This obsessional behavior has affected teenagers and college students. They are likely to log on computers and spend long hours at different websites.

    They become hooked on computers and gradually their social and school life is affected by this situation. They spend all free time surfing and don't concentrate on homework, so this addiction influences their grades and success at school. Because they can find everything on the websites, they hang out there. Moreover, this addiction to websites influences their social life.

    They spend more time in front of computers than with their friends. The relation with their friends changes. The virtual life becomes more important than their real life. They have a new language that they speak in the chat rooms and it causes cultural changes in society.

    Because of the change in their behavior, they begin to isolate themselves from the society and live with their virtual friends. They share their emotions and feelings with friends who they have never met in their life. Although they feel confident on the computer, they are not confident with real live friends they have known all their life. It is a problem for the future. This addictive behavior is beginning to affect all the world.