What are the contrast in the functions of red blood cells and neutrophils?

Red blood cells (RBCs) primarily function in the transportation of oxygen from the lungs to body tissues and carbon dioxide from tissues back to the lungs, relying on hemoglobin for this process. In contrast, neutrophils are a type of white blood cell that play a crucial role in the immune response by identifying and destroying pathogens, particularly bacteria, through phagocytosis and the release of antimicrobial substances. While RBCs are essential for maintaining oxygen levels in the body, neutrophils are critical for defending against infections and maintaining overall immune health.