Methemoglobin
Methemoglobin ( British: methaemoglobin ) ( pronounced "met-hemoglobin" ) is a hemoglobin "in the form of metalloprotein" , in which the iron in the heme group is in the Fe3+ ( ferric ) state , not the Fe2+ ( ferrous ) of normal hemoglobin . 
<triplet> hemoglobin <subj> metalloprotein <obj> subclass of <triplet> ferric <subj> iron <obj> has part