大众英语80篇背诵阅读带翻译(二)
"04 Electricity
The modern age is an age of electricity. People are so used to electric lights, radio, televisions, and telephones that it is hard to imagine what life would be like without them. When there is a power failure, people grope about in flickering candlelight, cars hesitate in the streets because there are no traffic lights to guide them, and food spoils in silent refrigerators.Yet, people began to understand how electricity works only a little more than two centuries ago. Nature has apparently been experimenting in this field for millions of years. Scientists are discovering more and more that the living world may hold many interesting secrets of electricity that could benefit humanity. All living cells send out tiny pulses of electricity. As the heart beats, it sends out pulses of record; they form an electrocardiogram, which a doctor can study to determine how well the heart is working. The brain, too, sends out brain waves of electricity, which can be recorded in an electroencephalogram. The electric currents generated by most living cells are extremely small -- often so small that sensitive instruments are needed to record them. But in some animals, certain muscle cells have become so specialized as electrical generators that they do not work as muscle cells at all. When large numbers of these cells are linked together, the effects can be astonishing. The electric eel is an amazing storage battery. It can send a jolt of as much as eight hundred volts of electricity through the water in which it lives. (An electric house current is only one hundred twenty volts.) As many as four-fifths of all the cells in the electric eel's body are specialized for generating electricity, and the strength of the shock it can deliver corresponds roughly to the length of its body.电当今期间是电气期间。人们对电灯、收音机、电视和电话早已习以为常乃至很难想象没有它们糊口会变成什么样。当停电时，人们在摇摆不定的烛光下黑暗摸索；因没有红绿灯的指示，汽车在路途上犹豫不前；冰箱也防止义务，招致食物蜕变。人们只是在两个世纪前一点才开始了解电的利用原理，天然界却显然在这方面经历过了数百万年。迷信家赓续发明良多生物世界里年夜概无益于人类的关于电的风趣秘密。全部生物细胞都会发出巨大的电脉冲。留神脏跳动时，把它发出的脉冲记实上去就成了心电图，这可让年夜夫了解心脏的义务状况。年夜脑也发出脑电波，这可在脑电图上记实上去。良多生物细胞发出的电流都是极巨大的，小到要用灵敏仪器本领记实和测量。但一些动物的某些肌肉细胞能转化成一个个发电机，乃至完全失落往肌肉细胞的功用。这种细胞年夜量地连接在一同时发作的结果将是极度令人受惊的。电鳗便是一种令人惊讶的蓄电池。它可以在水中发出相称于 800伏特电压电流(家庭用户的电压只要 120伏特)。在电鳗的身段里，多至五分之四的细胞都专门用来发电，并且发出的电流的强度年夜约和它身段的长度成反比。