[Oliver1975]

Hi there, does anyone know for which processes Rb is used or needed within biological systems? It doesn´t matter if these processes are restricted to humans, animals, shells or plants etc.... ?!?!
 

[jdurg]

I'm familiar with elemental rubidium, and all I can really say is that is has pretty much the same chemistry as sodium and potassium since it is in the same column of the periodic table.  I do not know of any biological processes off-hand which depend on rubidium, but I know that it can take the place of sodium and potassium in many chemical processes.  (Kind of like how plutonium is biologically and radiologically lethal since it can mimic calcium in the body and take it's place in your bones and tissues).

[AWK]

Read these papers:
http://www.dcnutrition.com/minerals/detail.cfm?RecordNumber=65,
http://www.dcnutrition.com/minerals/Detail.CFM?RecordNumber=49
and
Antagonism of certain elements essential to plants toward chemically related toxic elements
Hurd-Karrer, A.M.
Plant Physiol. ;14(1)  14-29 (1939)
where author stated that rubidium can affect potassium availability for plants.