in microscopic world, countless vibrant erythrocytes, red blood cells, traverse circulatory system, tirelessly carrying

red hypochromic erythrocytes hemoglobin bloodstream capillaries medical morphology ironrich rbcs oxygencarrying microcytes erythrocyte anemia heme hematopoiesis macrocytes oxygenation hematology bloodrelated lifespan blood erythropoiesis cell normocytic iron hematocrit health hematologist ai generated