With respect to structure of haemoglobin correct one is
comprises four polypeptide chain ( albumin portion )
iron present in the ferric state
Iron present in the ferrous state
comprises six polypeptide chain (globin portion ) .
As we learnt ,
Structure of Haemoglobin -
The Hb molecule comprises four polypeptide subunits (the globin portion) each of which has a heme group attached. At the center of the four heme groups is an atom of iron in the ferrous state. Oxygen binds reversibly to these four iron atoms; the product is oxyhemoglobin (O2Hb).
-