What is the mechanism for iron toxicity if iron is present in excess amounts?
a. Acts as a catalyst in forming free oxygen radicals
b. Impedes hematopoiesis
c. Reduces hemoglobin to methemoglobin
d. Interferes with globin synthesis
ANS: A
Iron has reduction (redox) potential, and easily cycles between ferrous (reduced) and ferric (oxidized) forms. If it is found in excess, then it plays a key role in forming harmful oxygen radicals that can damage cellular structures, thus harming cells in the process.
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