It's iron that is found in plants rather than animals. Animal product iron is called heme iron.
Elecctron transfer more information at http://www.scribd.com/doc/10322039/Csir-Ugc-Jrf-Net-Chemistry-Paper-1-Part-b-Series-1
vegetables
The deep red, non-protein, ferrous component of hemoglobin, C34H32FeN4O4...
iron doesnt oxidize when oxygen binds to haemoglobin. instead ion induced dipole attraction is present between iron and oxygen.source: my teacher and there's a bit about this on wikipedia. search for...