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 million 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 cell 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, cert 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 million 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 cell 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 cell are linked together, the effects can be astonishing.
The electric eel is an amazing storage battery. It can seed a jolt of as much as eight hundred volts of electricity through the water in which it live. As many as four-fifths of all the cells in the electric eels body are specialized for generating electricity, and the strength of the shock it can deliver corresponds roughly to length of its body.
ain muscle cells have become so specialized as electrical generators that they do not work as muscle cells at all. When large numbers of these cell are linked together, the effects can be astonishing.
The electric eel is an amazing storage battery. It can seed a jolt of as much as eight hundred volts of electricity through the water in which it live. As many as four-fifths of all the cells in the electric eels body are specialized for generating electricity, and the strength of the shock it can deliver corresponds roughly to length of its body.
美文赏析:难道真要工作一辈子吗?
惊人发现! 每天小剂量伟哥可能减少结直肠癌风险!
为什么你存不下钱
投其所好:互动电影根据观众反应定结局
2018年6月英语四级作文范文:人工智能
大家喝醉酒之后,真是各有各的搞笑
国内英语资讯:Myanmar-China Friendship Association eyes enhanced Myanmar-China ties
国内英语资讯:UNFPA to continue work with China on population, development: UN official
研究显示 生吃果蔬有利于心理健康
国内英语资讯:China Focus: Chinese moms embrace a smarter life this Mothers Day
The congestion caused by ride-hailing 叫车软件造成的交通拥堵难题
体坛英语资讯:Hamburg relegate for first time, Wolfsburg secure play-off in German Bundesliga
高空玻璃破碎! 川航完成“史诗级”备降 网友怒赞
国内英语资讯: Chinas top legislator meets AU Commission deputy chair, eyeing closer China-Africa coopera
体坛英语资讯:Paraguays Dominguez re-elected as CONMEBOL president
国内英语资讯:Chinese state councilor, Iranian foreign minister hold talks
国内英语资讯: Audio evidence of Japans germ war atrocities archived in China museum
人真的会因为心碎而死吗?
7月起部分高铁调整票价 最低6.5折
美国男孩在被宣布脑死亡后竟苏醒
即使是少量运动,也能带来幸福感
广州公立医院6岁以下儿童看病涨价三成
前马来西亚总理辞去政党领导人职务
国内英语资讯:Interview: Belt and Road Initiative features win-win for China, CEE -- expert
如何才能改变现状
Be-all and end-all?
NASA将向火星发射直升机,拍摄火星鸟瞰图!
漫威推出首批中国超级英雄,了解一下?
国内英语资讯:Economic Watch: Chinas financial opening up attracts global investors
论猫奴的自我修养:正确吸猫指南,教你博得主子欢心
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |