bloody haemoglobin!

Eating my breakfast, trying to focus on an upcoming biochemistry test (largely on oxygen-transporting metalloproteins) this (the title) was all I could think for a few seconds - quite depressing; then I realised the irony.

EDIT(2) - lol - 'irony', gettit??.. heme, iron - wow.

As for the 'Root Effect'; ah .. well, you can perhaps guess my thoughts around that one.

EDIT: after a few mins of study, I am more fond of haemoglobin. It is, like much of biochem, so freakin' clever. Whoever made this stuff, I take my hat off to you. As one of my first year lecturers said, (something like) "God is a very subtle biochemist - that's worth thinking about." Two negative allosteric effectors (which reduce oxygen binding, i.e. make haemoglobin give up the O2 it is holding) are carbon dioxide (indirectly, through reactions producing H+ and the Cl- shuttled into red blood cells, to replace hydrogencarbonate, by a Cl- transporter) and higher temperature. It just so happens that both of these conditions are found in exercising muscle, thus facilitating the exchange of O2 for CO2 here and keeping you folks alive. We see here a tight, tight relationship between the structure of the haemoglobin protein tetramer, its function (influenced in the 'right direction' by various different molecules/conditions) and its environment - but at the whole organism level of oxygen transport as well as at the molecular. E.g (as above): the temperature increase in skeletal muscle cells which is a side-effect of respiration also happens to affect the haemoglobin protein in the right way for it to function well when it reaches these cells.

More along vaguely similar lines, particularly on the relations between CO2 and HCO3- (as I recall) here: