switch on and off

基本解释

They are controlled by molecular triggers that switch on and off on demand.
它们由能够根据需要开启或关闭的触发分子控制。
The computer can be used to switch on and off the entire equipment on the electric station.
计算机可开关发电站的所有设备。
The electric station is controlled with the help of the mnemocircuit. The computer can be used to switch on and off the entire equipment on the electric station.
借助于简略电路对发电站进行控制。计算机可开关发电站的所有设备。

One way that you could switch this on and off inside the cell is by taking off this phosphorous, proteins enzymes that do this opposite reaction, the opposite to kinases are called phosphokinases.
一种方法是通过去除磷酸基团,来改变细胞内蛋白的状态,催化添加磷酸基团,此逆反应的蛋白酶,能够催化逆反应的激酶叫做磷酸激酶
耶鲁公开课 - 生物医学工程探索课程节选

It is not something that we can switch on and off whenever it suits us.
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But the ability to turn that switch on and off perfectly for others is a little like being able to walk a tightrope, chew gum, talk on the phone and solve a math problem at the same time.
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We're not exactly sure what makes these virus transistors so special, but apparently the transistors they've built out of the nano-coated strands, and sandwiched between two electrodes, are easy to switch between ON and OFF states, since they don't need to build up a charge at a lame-o capacitor before they can be switched.
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