Final answer:
Phagocytosis is when cells like neutrophils and macrophages engulf and digest large particles. It involves the particle's engulfment, formation of a phagolysosome, enzymatic digestion, and expulsion of residues.
Step-by-step explanation:
Phagocytosis is a critical process of the immune system where cells, commonly white blood cells like neutrophils and macrophages, engulf and digest large particles such as pathogens or cellular debris. The stages of phagocytosis include:
- The engulfment of the pathogen by the extension of the cell membrane.
- The encasement of the pathogen within a vesicle known as a phagosome.
- The fusion of the phagosome with a lysosome to form a phagolysosome.
- The release of hydrolytic enzymes within the lysosome that destroy the pathogen.
- The expulsion of undigested materials from the cell through exocytosis.
This multi-step immune response is not only effective at removing harmful invaders but also plays a role in cleaning up cellular debris and other particulates within the body.