switch on and off

基本解释

They are controlled by molecular triggers that switch on and off on demand.
它們由能夠根據需要開啓或關閉的觸發分子控制。
The computer can be used to switch on and off the entire equipment on the electric station.
計算機可開關發電站的所有設備。
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.
借助於簡略電路對發電站進行控制。計算機可開關發電站的所有設備。

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.
一種方法是通過去除磷酸基團,來改變細胞內蛋白的狀態,催化添加磷酸基團,此逆反應的蛋白酶,能夠催化逆反應的激酶叫做磷酸激酶
耶魯公開課 - 生物毉學工程探索課程節選

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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