In regulated secretion, the exocytosis process is not completed until a specific signal enters the cell. Clicking
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When glucose molecules enter the cell, a sequence of events is put into action that results in the fusion of the secretory vesicles with the plasma membrane of the cell.
Exocytosis is completed as the fusion of the secretory vesicles into the cell membrane releases insulin into neighboring blood capillaries.
The released insulin goes on to stimulate the release of glucose receptors into the membranes of additional cells, also by the exocytosis process.