What is the difference between hemoglobin and oxyhemoglobin?

hemoglobin is the carrier of ##"O"_2## and ##"CO"_2## in the blood.

hemoglobin is a molecule made up of two chains ##alpha## and ##beta## chains each chain has iron atom at the center see the structure below. marked with Fe. iron here is in +2 oxidation state. ready to take up the oxygen molecule.

haemoglobin is present in RBCs nad when they reach Oxygen rich region in lungs specifically Alveoli, iron changes its oxidation state to +3 and then the haemoglobin gets converted to oxyhemoglobin.

oxyhemoglobin delivers ##"O"_2## in the region where there is requirement for it and in turns takes up the ##"CO"_2## to remove it from body.

thus oxyhemoglobin is nothing but the hemoglobin carrying ##"O"_2##

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