The life span of a red blood cell is approximately how many days?

The life span of a red blood cell is approximately 120 days. This duration reflects the time it takes for red blood cells to circulate through the body, where they transport oxygen from the lungs to various tissues and return carbon dioxide from those tissues back to the lungs.

After about 120 days, red blood cells are typically removed from circulation by the spleen and other organs, as their membranes start to break down and they lose their functionality. This 120-day lifespan is a critical factor in understanding hemoglobin levels and overall blood health, especially in contexts such as anemia or other hematologic conditions.

The other options do not accurately reflect the typical lifespan of red blood cells; for instance, 30, 60, and 90 days are significantly shorter periods, which would not allow enough time for adequate oxygen transport and functionality within the body system. Understanding the correct lifespan is crucial for professionals involved in treatment planning, especially in the management of chemotherapy and potential impacts on blood cell production.