Granulocytes, including neutrophils, are distinguished from the other category of leucocytes - which are called agranulocytes, because granulocytes contain chemical-filled cytoplasmic vesicles called granules.
- 60 - 70% of all white blood cells are neutrophils.
- Neutrophils are 10-12 um in diameter
- have nuclei that have 2-5 lobes, and
- cytoplasm that includes very fine pale lilac granules.
Neutrophils are the first leucocytes to respond to bacterial invasion of the body.
They act by carrying out the process of phagocytosis and also by releasing enzymes - such as lysozyme, that destroy certain bacteria.
Phagocytosis is the engulfment and digestion of bacteria and other antigens by phagocytes, as shown:
For more information about other components (sometimes called the 'constituents') of blood, see the page about the structure and functions of blood. This may interest students of holistic massage, reflexology, beauty therapies, or health-related courses.