Porphyrin of normal erythrocyte haemoglobin is: (A) Coproporphyrin I, (B) Uroporphyrin III, (C) Protoporphyrin III, (D) Uroporphyrin I
Answer is C. Heme is iron containing protoporphyrin. Protoporphyrins are named according to the side chains, i.e. Methyl, vinyl, propionyl.