White blood cell. Coloured scanning electron micrograph (SEM) of a white blood cell (grey, centre left) migrating into a blood vessel. This newly form

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White blood cell. Coloured scanning electron micrograph (SEM) of a white blood cell (grey, centre left) migrating into a blood vessel. This newly formed white blood cell or lymphocyte has come from the bone marrow where it was produced. It is entering the lumen of the blood vessel where it will become part of the bloodstream. White blood cells are elements of the immune system of the body. Their main function is to recognise foreign bodies (such as bacteria) and to play a role in destroying them. White blood cells are produced constantly by the bone marrow as their lifespan is short. Magnification: unknown.

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Size: 4799px × 6735px
Photo credit: © ROBERT BECKER, CUSTOM MEDICAL STOCK PHOTO/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, blood, body, bone, cell, cells, enter, enters, exits, human, immune, lymphocyte, marrow, migration, vessel, white