Vesicle (biology)

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Organization of a typical eukaryotic animal cell:
1. Nucleolus (nuclear body)
2. Cell nucleus (nucleus)
3. Ribosomes
4. Vesicle
5. Rough (granular) ER (ergastoplasm)
6. Golgi apparatus
7. Cytoskeleton
8. Smooth (agranular) ER
9 . mitochondria
10. lysosome
11. cytoplasm (with cytosol and cytoskeleton )
12. peroxisomes
13. centrioles
14 cell membrane
Vesicle (scheme)

Vesicles ( Latin for vesicula , 'vesicles' ) in biology are intracellular (located in the cell ), very small, round to oval vesicles that are surrounded by a single or double membrane or a network-like shell made of proteins . The vesicles form their own cell compartments in which different cellular processes take place. Their size is about one micrometer . Vesicles are responsible for the transport of many substances in the cell.

There are several functionally different types of vesicles. Substances are stored in exocytotic vesicles that are intended to be released from the cell by fusing the vesicles with the cell membrane . These can also be membrane proteins that are initially located in the vesicle membrane and automatically belong to the cell membrane after the fusion. Another example are synaptic vesicles for the release of neurotransmitters . Conversely, endocytotic vesicles serve to internalize substances into the cell and to recycle membrane proteins. Other vesicles are used to transport newly generated proteins from the endoplasmic reticulum (ER) to the Golgi apparatus . Gas vesicles give aquatic protozoans buoyancy and enable them to stay in an optimal water depth.

See also

literature

  • Werner Linß, Jochen Fanghanel (Ed.): Histology. Cytology, General Histology, Microscopic Anatomy . De Gruyter textbook. Walter De Gruyter, Berlin / New York 1998, ISBN 3-11-014032-2 , p. 25th ff .
  • Robert F. Schmidt, Florian Lang (ed.): Human physiology with pathophysiology . 29th edition. Springer, Heidelberg 2005, ISBN 3-540-21882-3 , pp. 10 ff .
  • Horst Bayrhuber, Ulrich Kull (ed.): Linder Biologie . Bildungshaus Schulbuchverlage, Braunschweig 2006, ISBN 978-3-507-10930-8 , p. 37 .