What is the primary function of red blood cells (RBCs)?

The primary function of red blood cells (RBCs) is to carry oxygen from the lungs to the tissues throughout the body and to transport carbon dioxide from the tissues back to the lungs for exhalation. This crucial role is facilitated by hemoglobin, a protein within RBCs that binds to oxygen molecules, allowing for efficient transport. The ability to exchange gases is vital for cellular metabolism and overall homeostasis, making this function fundamental to life.

While other cells and components of blood handle nutrient transport and immune response, red blood cells are uniquely specialized for gas exchange, which distinguishes their primary function from those roles.