Encyclopedia > Exocytosis

  Article Content

Exocytosis

In biology, exocytosis is the process of a biological cell releasing substances into the extracellular fluid[?] (its environment). Exocytosis is the opposite of endocytosis.

Process

Vesicles that contain the substances to be released are transported to the plasma membrane and fuse with it. This accomplishes three tasks:
  1. The total surface of the plasma membrane increases (by the surface of the fused vesicle). This is important for the regulation of cell size, e.g., during cell growth.
  2. The substances within the vesicle are released into the exterior. This can be waste products or toxins, but also signalling molecules like hormones or neurotransmitters during synaptic transmission.
  3. Proteins that are embedded in the vesicle membrane are now part of the plasma membrane. The side of the protein that was facing the inside of the vesicle is now facing the outside of the cell. This mechanism is important for the regulation of transmembrane receptors and transporters.



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Great River, New York

... family size is 3.36. In the town the population is spread out with 29.0% under the age of 18, 5.0% from 18 to 24, 29.0% from 25 to 44, 24.2% from 45 to 64, and 12.7% ...

 
 
 
This page was created in 21.6 ms