phagosome

biology

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July 15, 2026

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A phagosome is a vacuole formed within a phagocyte, a type of cell that engulfs and digests foreign particles like bacteria. This process, called phagocytosis, is a key part of the immune response in higher animals, helping to defend against infection.12

Phagocytes, such as white blood cells like macrophages and neutrophils, extend their cytoplasm to surround and ingest foreign material. This material is then enclosed in a vacuole, the phagosome, where it is digested by enzymes secreted by the cell. This mechanism is crucial for clearing the body of pathogens and cellular debris.12

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phagocytosis
Particle engulfment and digestion
…a membrane-bound vacuole called a phagosome. The phagocyte digests the ingested particle with hydrolytic enzymes, which are contained within membrane-enclosed sacs called lysosomes found within the cell. Phagocytic enzymes are secreted into the vacuole in which digestion takes place. Small organic components of the particle are used to build larger…
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…a membrane-bound vacuole called a phagosome. The phagocyte digests the ingested particle with hydrolytic enzymes, which are contained within membrane-enclosed sacs called lysosomes found within the cell. Phagocytic enzymes are secreted into the vacuole in which digestion takes place. Small organic components of the particle are used to build larger…
Read More