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How do white blood cells differ from red blood cells in structure and function?
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white blood cell
Blood is made up of multiple components, including red blood cells, white blood cells, platelets, and water-rich plasma.
White blood cells (leukocytes) and red blood cells (erythrocytes) differ significantly in their structure and biological roles.
Structural Differences
- Nucleus: Unlike mature red blood cells, which lack a nucleus to maximize space for hemoglobin, white blood cells are nucleated.12
- Shape and Size: Red blood cells are small, biconcave disks approximately 7.8 μm in diameter. In contrast, white blood cells are generally larger; for example, granulocytes measure approximately 12–15 μm and possess multilobed nuclei and cytoplasmic granules.324
- Motility: White blood cells are capable of independent motility, allowing them to move through tissues, whereas red blood cells circulate passively.15
Functional Differences
- Primary Role: The main function of red blood cells is the transport of oxygen and carbon dioxide throughout the body. White blood cells are specialized for the body’s defense, protecting against infection and disease by destroying pathogens, producing antibodies, and mediating inflammation.6215
- Metabolism: White blood cells have more complex chemical pathways and can synthesize protein, while red blood cells rely on glycolysis for energy and do not consume the oxygen they transport.12