Are ions always aqueous inside the cell? (simple question)

[sameeralord]

Hello guys,

So there are hydrogen ions inside the cell which is pumped out in cellular respiration. Now my question is when they say hydrogen ions are inside the cell are these actually dissolved in water, ions can not exist without being dissolved right, why is that they are so reactive otherwise. Also in diffusion when they say hydrogen ions are taken in by the cell, does water come with it because they are dissolved. So does osmosis and ion diffusion occur together. Thanks

 

[somasimple]

So does osmosis and ion diffusion occur together.

A good but complex question for sure.

 

[Mapes]

There are at least a couple mechanisms by which hydrogen ions could move into the cell. They can be transported while dissolved in water, yes, but lone protons can also be transported through membrane pumps. Here they aren't dissolved in water but are rather transferred between transmembrane proteins. This is described in detail in cell biology texts that focus on the plasma membrane.

 

[somasimple]

There is a third but accepted mechanism : No pump, no protein and it works fine.
http://www.amolf.nl/news/news-archive/detailpage/back_to/news-archive/article/water-lends-protons-a-helping-hand//chash/ddde2cfa66/
http://www.spectroscopynow.com/coi/cda/detail.cda?id=10474&type=Feature&chId=2&page=1

Protons do not move freely in water, but form complexes with water molecules through hydrogen bonds, which allow protons to hop through water very efficiently. "One could use the picture of improving a dike with sandbags", explains Nibbering. A chain of people can transport the sandbags to the dike more efficiently and faster than each person working individually. Thus, protons hope from water molecule to molecule, just as sandbags hop from person to person.