What is the mechanism of exocytosis?

Expert Answers
cburr eNotes educator| Certified Educator

Exocytosis is the process cells use to get rid of waste and excess chemical transmitters like hormones.

A vesicle (a small bubble of liquid inside the cell) traps the waste products. It then floats around in the cytoplasm of the cell until it gets near the cell membrane. Once it gets close, it gets pulled toward the cell membrane (the outside edge of the cell) and then merges with the cell membrane. Finally, a hole opens up in the vesicle/membrane and lets the waste products out of the cell.

helen75 | Student

Exocytosis is the cellular process by which cells excrete waste products or chemical transmitters. During this, the materials packaged in vesicles are secreted from a cell when the vesicle membrane fuses with the plasma membrane. The initial event in this process is the binding of a membrane protein protruding from the cytoplasmic side of the vesicle with a membrane protein on the cytoplasmic side of the target site on the plasma membrane. The phospholipid regions of the two membranes merge, and an opening to the outside of the cell develops. The contents of the vesicle are released to the environment, and the vesicle membrane is smoothly incorporated into the plasma membrane.