From day one, the Iranian authorities have been complaining about the creation of this channel,".

VOA: standard.2009.07.02

It can exist in - a gated ion channel - can exist in one or two states.

它们能够存在于,门控离子通道有一种或者两种状态

耶鲁公开课 - 生物医学工程探索课程节选

The one that's on the top here is called ligand-gated ion channel and an ion channel is a protein that sits in the surface of a cell.

最上面的这个叫作配体门控离子通道,离子通道是一类位于细胞表面的蛋白

耶鲁公开课 - 生物医学工程探索课程节选

And that's all that's big enough to pass through or small enough to pass through. And if we go up even just one row on the periodic table to potassium, what we actually see is now that it's going to be too large, and, in fact, a potassium solvated with one water molecule won't go through our channel.

就是这样刚好大到它通过,或者说刚好小到它通过,即使我们再沿着周期表往下走仅仅一行到钾离子，我们看到的就将是它的个头太大了，实际上，溶解于一个水分子的单个钾离子,不能穿过我们的通道。

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