Which pigment is released when red blood cells are broken down?

Study liver anatomy and function with our medical students test. Engage with detailed multiple choice questions, each with hints and explanations. Prepare effectively for your test!

When red blood cells are broken down, the heme portion of hemoglobin is degraded to bilirubin, a bile pigment. This bilirubin is released and transported to the liver for conjugation before being excreted into bile. In the gut, bilirubin can be converted to urobilinogen and then to urobilin (and stercobilin), which give urine and stool their colors. So the pigment directly released from RBC breakdown is bilirubin. Hemoglobin is the oxygen-carrying protein, not a pigment released; melanin is a skin pigment, unrelated to red cell breakdown; urobilin is a downstream product of bilirubin processing.