This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'The number of Fe++ atoms in one Hb molecule \nSelect and explain. \nA. 1, B. 2, C. 4, D. 8', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Hemoglobin is a globular molecule made up of four subunits. Each subunit contains a heme moiety conjugated to a polypeptide. Heme is an iron-containing porphyrin derivative.\nSo, hemoglobin = 4 globins + 4 heme groups Since each heme molecule contains an iron, so total iron atoms present in\xa0hemoglobin are 4 in number.\n70% of the iron in the body is in hemoglobin, 3% in myoglobin, and the rest in ferritin, which is present not only in enterocytes, but also in many other cells.', 'role': 'assistant'}]