What is the primary function of red blood cells?

The primary function of red blood cells is to carry oxygen throughout the body. This is achieved due to the presence of hemoglobin, a protein within red blood cells that binds to oxygen molecules in the lungs and then transports them to the tissues and organs. In addition to oxygen delivery, red blood cells also play a role in transporting carbon dioxide, a waste product, from the tissues back to the lungs, where it can be exhaled.

While other blood components, such as white blood cells, are responsible for fighting infections, and platelets play a key role in blood clotting, these functions are distinctly separate from the primary role of red blood cells. Hormone production is a function of glands within the endocrine system, not red blood cells. Thus, the emphasis on transporting oxygen highlights the core role of red blood cells in maintaining physiological functions and overall health.