The lifespan of red blood cells is:

🧠 Explanation:

The lifespan of red blood cells is 120 days, supporting circulation. For biology students, this highlights human physiology, making it a key topic for studying hematology, medicine, and biology. Cells sustain life. Understanding this clarifies body functions. It’s essential for analyzing biology, medicine, and health sciences. Studying red blood cells offers insights into how circulation works, crucial for biology, medicine, and health sciences.