Erythrocytes

Erythrocytes, or red blood cells, are the most ubiquitous cells in a blood smear. They appear as biconcave discs of uniform shape and size that lack organelles and granules. Red blood cells have a characteristic pink appearance due to their high content of hemoglobin, which is basic. The central pale area of each red blood cell is due to the concavity of the disc. Also visible in this slide are several platelets, which play a crucial role in the blood clotting cascade.