Question

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

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

Explanation:

To solve this, we recall the heme degradation pathway. After iron is removed from heme (in hemoglobin breakdown), the remaining heme is converted first to biliverdin, and then biliverdin is converted to bilirubin. Let's analyze the options:

• "Uric acid and then biliverdin": Incorrect, as uric acid is from purine metabolism, not heme.
• "Urochrome and then uric acid": Urochrome is a pigment in urine, and uric acid is not part of heme degradation. Incorrect.
• "Biliverdin and then bilirubin": Matches the heme degradation steps (heme → biliverdin → bilirubin after iron removal). Correct.
• "Macrophages and then bilirubin": Macrophages are cells that process heme, but the chemical conversion of heme (after iron) starts with biliverdin, not macrophages as the first product. Incorrect.

Answer:

C. Biliverdin and then bilirubin (assuming the third option is labeled C; if the original options had labels like A, B, C, D, the correct one is the option with "Biliverdin and then bilirubin")