How does phagocytosis happen?

Phagocytosis occurs in 4 main steps. 

1. Recognition of the Target Particle: The cell identifies and binds to the particle that needs to be engulfed. This particle could be a pathogen, dead cell, or debris.
2. Signaling to Activate the Internalization Machinery: After binding, intracellular signaling pathways are activated. This signaling involves various molecules and proteins that trigger changes in the cell’s cytoskeleton. 
3. Phagosome Formation: The phagocyte's membrane engulfs the target particle, enclosing it within a newly formed vesicle called a phagosome. 
4. Phagolysosome Maturation: This step involves the maturation of the phagosome into a phagolysosome. This process includes the fusion of the phagosome with lysosomes; the phagolysosome is then capable of breaking down and digesting the engulfed particle.