Source of bilirubin Senile red blood cell(rBC) 80-85% RBCS lifetime: about 120 days Immature rBc 10-15% Others 1-5%. like free heme in liver and some proteins containing hemeSource of Bilirubin • Senile red blood cell (RBC) 80~85 % RBC’s lifetime: about 120 days • Immature RBC 10~15% • Others 1~5%, like free heme in liver and some proteins containing heme