Final answer:
In phagocytosis, the phagosome combines with a lysosome to form a phagolysosome, which digests the pathogen with hydrolytic enzymes and acids.
Step-by-step explanation:
In phagocytosis, the phagosome that contains the pathogen fuses with an enzyme-rich vesicle known as the lysosome. This fusion results in the formation of a phagolysosome, a compartment where the ingested pathogen is killed and digested by hydrolytic enzymes and acidic contents from the lysosome. This process is crucial in the immune system's defense against invasion by pathogens, and it is carried out by specialized immune cells such as macrophages, neutrophils, and dendritic cells.
These cells engulf and destroy pathogens as part of the innate immune response. Some pathogens can evade this defense mechanism and survive within phagocytes. When the phagosome fuses with the lysosome, it forms a phagolysosome where the pathogen is killed and digested.