What is the primary function of red blood cells?

The primary function of red blood cells, or erythrocytes, is to transport oxygen throughout the body. They achieve this through the presence of hemoglobin, a specialized protein that binds to oxygen in the lungs and releases it in tissues where it is needed for cellular respiration. This process is crucial because oxygen is essential for the production of energy in cells, which is vital for all bodily functions.

While other components of the blood contribute to different physiological processes—such as white blood cells that defend against infections and platelets that aid in clotting—red blood cells are uniquely specialized for oxygen transport. By efficiently delivering oxygen and also aiding in the removal of carbon dioxide (a waste product of metabolism), red blood cells play a key role in maintaining overall homeostasis within the body.