Then,there are these pores that when they exist and when they're open,

同时有通道蛋白这样的孔洞
are letting these molecules to leak back the other way.

开放时任由离子漏回
The pump always has to be operating

钠-钾泵必须持续工作
because the leak is always happening.

因为渗漏一直存在
Does that make sense?

明白了吗
Because you have these differences in ion concentrations

由于胞膜内外的离子浓度
across the cell membrane these--

存在这些差异
and you have the flux of molecules continuously across the membrane.

分子才可以持续地跨膜流动
What I've shown here are channels that are--

这里展示的是通道蛋白
they have a lid on them so they're sometimes open and sometimes closed,

通道有阀门可以时而开放时而关闭
they can be both opened and closed.

同一时间有开有关
Every cell in your body at a given time is going to

机体内的每个细胞在特定的时间