<prompt> The initiation of hemoglobin synthesis requires:HistidineGlycineFolateIron  <response>: Ans. b GlycineRef: Harpers Biochemistry, 30th ed. pg. 326-28 Heme is synthesized in a complex series of steps involving enzymes in the mitochondrion and in the cytosol of the cell The first step in heme synthesis takes place in the mitochondrion. Steps in heme synthesis are: Condensation of succinyl CoA and glycine by ALA synthase to form 5-aminolevulic acid ALA. 5 ALA is transported to the cytosol where a series of reactions produce a ring structure called coproporphyrinogen III. This molecule returns to the mitochondrion where an addition reaction produces protoporphyrin IX. The enzyme ferro chelatase inserts iron into the ring structure of protoporphyrin IX to produce heme. 