exocytosis

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Endocytosis and exocytosis

Diagram illustrating exocytosis in cell biology, showing how secretory vesicles from the Golgi apparatus fuse with the cell membrane to release proteins, with pathways for both regulated and unregulated secretion labeled.

exocytosis

biology

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June 26, 2026

Quick Summary

Endocytosis and exocytosis — Endocytosis and exocytosis The process of intracellular digestion involves endocytosis and exocytosis. Food particles are taken into the cell via endocytosis into a vacuole. Lysosomes attach to the vacuole and release digestive enzymes to extract nutrients. The leftover waste products of digestion are carried to the plasma membrane by the vacuole and eliminated through the process of exocytosis.

Exocytosis is a biological process where cells release substances to the outside. This occurs when membrane-bound sacs, called vesicles, fuse with the cell's outer membrane (plasma membrane). The contents of these vesicles are then expelled from the cell.12

This process is crucial for exporting materials synthesized within the cell, such as proteins and neurotransmitters. The cell membrane acts as a barrier, controlling what enters and leaves the cell, and exocytosis is a key mechanism for the controlled release of cellular products.12

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cell membrane
Transport of substances
…internal medium is externalized (exocytosis). These movements involve a fusion between membrane surfaces, followed by the re-formation of intact membranes.
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…internal medium is externalized (exocytosis). These movements involve a fusion between membrane surfaces, followed by the re-formation of intact membranes.
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exosome
Exosomes are secreted via exocytosis by a variety of cell types, including cancer cells, and subsequently are taken up by target cells, where they communicate information via surface protein signaling as well as through the transfer of lipids, nucleic acids, and other biomolecules. Intercellular communication by exosomes plays a…
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Exosomes are secreted via exocytosis by a variety of cell types, including cancer cells, and subsequently are taken up by target cells, where they communicate information via surface protein signaling as well as through the transfer of lipids, nucleic acids, and other biomolecules. Intercellular communication by exosomes plays a…
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Golgi apparatus
Protein trafficking and modification
…to the cell membrane for exocytosis (release into the extracellular environment). The exocytosis of secretory proteins may be regulated, whereby a ligand must bind to a receptor to trigger vesicle fusion and protein secretion. In addition, within the vesicles are proteases that cut many secretory proteins at specific amino acid…
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…to the cell membrane for exocytosis (release into the extracellular environment). The exocytosis of secretory proteins may be regulated, whereby a ligand must bind to a receptor to trigger vesicle fusion and protein secretion. In addition, within the vesicles are proteases that cut many secretory proteins at specific amino acid…
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nervous system
Neurotransmitter release
This expulsion process is called exocytosis. Vesicle membranes are then recovered from the plasma membrane through endocytosis. In this process the membranes are surrounded by a protein coat at the lateral margins of the synapse and are then transferred to cisternae, which form in the terminal during nerve stimulation. There…
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This expulsion process is called exocytosis. Vesicle membranes are then recovered from the plasma membrane through endocytosis. In this process the membranes are surrounded by a protein coat at the lateral margins of the synapse and are then transferred to cisternae, which form in the terminal during nerve stimulation. There…
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cell
Exocytosis
In exocytosis, material synthesized within the cell that has been packaged into membrane-bound vesicles is exported from the cell following the fusion of the vesicles with the external cell membrane. The materials so exported are cell-specific protein products, neurotransmitters, and a variety of other…
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In exocytosis, material synthesized within the cell that has been packaged into membrane-bound vesicles is exported from the cell following the fusion of the vesicles with the external cell membrane. The materials so exported are cell-specific protein products, neurotransmitters, and a variety of other…
Read More