Phagocytosis. Coloured scanning electron microg- raph (SEM) of a macrophage white blood cell (light brown) engulfing several Escherichia coli (E. coli

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Phagocytosis. Coloured scanning electron microg- raph (SEM) of a macrophage white blood cell (light brown) engulfing several Escherichia coli (E. coli) bacteria (pink rods). E. coli are normally present in vast numbers in the intestines of most mammals. They are not usually pathogenic in this situation. Under certain conditions, however, E. coli may be responsible for diarrhoea, enteritis and urinary tract infections. Here, the macrophage has extended parts of its body to surround and capture the E. coli bacteria. This process is called phagocytosis. Macrophages are part of the immune system that keep the body free of invading organisms. Magnification: x1,750 at 5x7cm size. x1900 at original

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Size: 4000px × 3028px
Photo credit: © EYE OF SCIENCE/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., anatomy, bacteria, blood, body, cell, cells, coli, defence, eating, escherichia, human, immune, immunology, macrophage, phago, phagocytosis, response, system, type, white