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How do red blood cells and white blood cells perform different functions in blood?

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Diagram explaining ATP's role in powering cellular activities, with arrows showing ATP produced by mitochondria, chloroplasts, and glycolysis, and used for making biomolecules, transporting substances, and driving energy-requiring processes; includes a structural diagram of ATP with labeled adenine, ribose, and phosphate groups. — Physiology Adenosine triphosphate (ATP) is the power source of many biochemical reactions. It is produced in the cell structures and system listed at the left to energize the important life processes listed on the right. An abbreviated chemical formula of the structure of ATP is also shown. The two high-energy P―O―P bonds are responsible for its power.

Red blood cells and white blood cells perform distinct, specialized roles in the body, primarily facilitated by their unique structures and compositions.

Red Blood Cells (Erythrocytes)

The primary function of red blood cells is the transport of gases. They contain hemoglobin, an iron-rich protein that binds to oxygen in the lungs and delivers it to tissues throughout the body. They also assist in transporting carbon dioxide, a metabolic waste product, from the tissues back to the lungs for excretion. Mature red blood cells lack a nucleus and mitochondria, which maximizes internal space for hemoglobin and ensures the cells do not consume the oxygen they are transporting.123

White Blood Cells (Leukocytes)

White blood cells are essential for the body's immune system. Unlike red blood cells, they contain a nucleus and are capable of motility, allowing them to travel to sites of infection or inflammation. Their functions include:45
* Phagocytosis: Granulocytes and monocytes ingest and destroy bacteria, foreign materials, and cellular debris.467
* Immunity: Lymphocytes are responsible for specific immune responses, such as producing antibodies to neutralize pathogens or destroying virally infected and cancerous cells.56

While red blood cells act as a transport system for life-sustaining gases, white blood cells function as a mobile defense force against disease and infection.47