What is the function of red blood cells?

Red blood cells (RBCs), also known as erythrocytes, have the primary function of carrying oxygen from the lungs to various tissues throughout the body and transporting carbon dioxide back to the lungs for exhalation. This critical role is facilitated by hemoglobin, a protein within red blood cells that binds to oxygen and carbon dioxide. Oxygen is essential for the survival of cells, allowing them to produce energy through cellular respiration. The effectiveness of red blood cells in this oxygen transport function is vital for maintaining overall health and supporting the metabolic activities of all bodily systems.

While other cells and components in the body are responsible for fighting infection (such as white blood cells), clotting blood (platelets), and providing structural support (various cells and connective tissues), red blood cells do not perform these functions. Instead, their specialized structure and composition make them uniquely suited for their role in oxygen delivery, which is fundamental to sustaining life.