neutrophils

• • Neutrophils are the commonest type of white blood cell
  • They have a lobed shaped nucleus (not rounded like the lymphocyte nucleus)
• Phagocytes

  • Pathogen is enclosed in a phagosome
  • Digestive enzymes (from lysosomes) are released into the phagosome
  • Pathogen is engulfed by neutrophil
  • The waste materials are released by exocytosis
  • The enzymes digest the pathogen
• Neutrophils and lymphocytes similarities

  • Both cells have nuclei/mitochondria/RER/ribosomes.
  • Both cells are made from stem cells that are in the bone marrow (of long bones).
  • Both are transported in blood plasma, migrate to tissue fluid and are present in the lymphatic system to provide defence against pathogens
• Neutrophils and lymphocytes differences

  • There are 3x as many neutrophils as T and B lymphocytes combined.
  • T and B cells have a large nucleus and are smaller than neutrophils.
  • Neutrophils have a lobed nucleus which makes the cell flexible and able to squeeze through the capillary wall. Lymphocytes cannot do this and remain in the blood.
  • They have antigen receptors on its cell surface membrane which can bind to antigens on a pathogen whereas a neutrophil does not.