Well the red blood cells ( erythrocytes) contain the oxygen carrying pigment known as haemoglobin. Hence RBCs carry oxygen to every cell ion the body.
The white blood cells ( leukocytes) form the cell mediated defence system of the body, they kill microbes and foreign particles either by phagocytosis or lysozymic reactions.
The platelets (thrombocytes) help in the blood clotting process.
This is my comparism of tne blood components.
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