Why do red blood cells maintain Iron in the Haem group in the +2 (ferrous) oxidation state?
A lot of sources tell me that RBCs contain a number of enzymes, and that these serve multiple functions from maintaining the structure and elasticity of the corpuscle wall, to preventing the oxidation of iron (ferrous) in Haemoglobin to the +3 Ferric state.But what none of them say, is what problems (if any) arise when the iron is oxidised. Hence the question, why avoid the Ferric state?I'm still a high-schooler and from what I've learnt, is that the higher the oxidation state of the cation, the higher its polarising power (Fajan's Rules) hence stronger the bond. So wouldn't iron in the Ferric state be able to bind with oxygen better, and isn't that desirable? ( Or is oxygen *release* to tissues going to be problematic? )If the Ferric state is desirable, then why do RBCs have mechanisms (the enzymes mentioned earlier) in place to *prevent* the oxidation of the Ferrous to the Ferric state?Thanks!