B0007650 Red and white blood cells
Credit: Maurizio De Angelis. Wellcome Images
An illustration showing red blood cells and white blood cells in circulation. Red blood cells (erythrocytes) are concave in shape and lack a nucleus allowing for the efficient transport of oxygen to the various tissues of the body, oxygen is carried in the form of haemoglobin, which also gives the red blood cells their red colour. White blood cells (leukocytes) are important cells of the immune system, which circulate in the blood and target sites of infection.
Digital artwork/Computer graphic
2010 Published: –

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