Question

multiple choice question
after removal of iron from hemoglobin, the remainder of the heme is converted into which of the following?

• urochrome and then uric acid
• biliverdin and then bilirubin
• macrophages and then bilirubin
• uric acid and then biliverdin

Explanation:

To solve this, we recall the heme breakdown pathway. After iron is removed from heme (from hemoglobin), the porphyrin ring of heme is first converted to biliverdin, and then biliverdin is converted to bilirubin. Let's analyze each option:

• "Urochrome and then uric acid": Urochrome is a pigment in urine, and uric acid is a purine metabolite, not part of heme breakdown. Eliminate.
• "Biliverdin and then bilirubin": Matches the heme breakdown steps (heme → biliverdin → bilirubin after iron removal).
• "Macrophages and then bilirubin": Macrophages are cells that process hemoglobin, but the heme remainder (after iron) is converted to biliverdin first, not macrophages. Eliminate.
• "Uric acid and then biliverdin": Uric acid is not part of heme breakdown, and the order is wrong. Eliminate.

Answer:

B. Biliverdin and then bilirubin