Which organ is primarily responsible for breaking down erythrocytes and recycling components such as hemoglobin?

• A. Liver
• B. Kidney
• C. Spleen
• D. Pancreas

Answer: (C)

Old red blood cells are removed from circulation primarily by macrophages in the spleen. In the splenic red pulp, these macrophages engulf senescent erythrocytes and break down hemoglobin. The globin portion is recycled as amino acids, while the heme portion is split into iron and bilirubin. Iron is recovered and returned to the bloodstream to be reused in new hemoglobin synthesis, and bilirubin is transported to the liver for processing and excretion in bile. The spleen’s role as the main site of erythrocyte destruction and recycling makes it the best answer; the liver assists by processing bilirubin and storing iron, but it is not the primary site of RBC destruction.