Well, imagine if that change in structure could be switched on and off by addition of a phosphorous; and in fact it can in many proteins.

那么,想象一下,只需引入磷酸基团,就能导致蛋白质的结构发生变化,事实上很多蛋白质就是如此

耶鲁公开课 - 生物医学工程探索课程节选

So if you haven't clicked in yet, or if you want to change your answer, keep in mind that you might need to jot down, - for example, a Lewis structure before you can answer this question.

如果你还没有点答案，或者你想改变你的答案，记住你也许需要在回答问题前写点东西，比如画一画Lewis结构,来得到最终。

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