Multiple choice general knowledge What is the average life span of a single red blood cell ? 120 minutes 120 hours 120 seconds 120 days Reveal answer Fill a bubble to check yourself D Correct answer Explanation Red blood cells (erythrocytes) have an average lifespan of approximately 120 days. After this period, they are removed from circulation by the spleen and liver, and new RBCs are continuously produced in bone marrow.