Soma (cell biology)
The Soma (from the Greek το σῶμα Soma , body ') is a technical term of biology and is used at two levels. It has a narrow meaning in cell biology and a broad meaning in the developmental biology of animals.
- Term used in cell biology: Here the soma simply refers to the body of a cell , the cytosoma (from κύτος kýtos 'cavity' for 'cell'). This view excludes cell processes and occasionally the cell nucleus . The main part of the metabolism takes place in the cell soma . The soma of nerve cells (neurons) in the area around the nucleus is also known as the perikaryon .
- Concept of developmental biology in animals: Here, the soma comprises the main body of cells that separated from the germline at an early embryonic stage . Only the cells of the germ line can form gametes (germ cells), because only they can go through meiosis . Germline cells can usually be recognized by their location in the embryo. Plants do not show a fundamental separation of soma and germ line, because many plant cells retain the ability to meiosis. Mutations in somatic cells disappear with the death of an individual. In contrast, if mutations in germline cells contribute to fertilization , they are passed on to offspring.
Web links
Individual evidence
- ↑ Benninghoff: Macroscopic and microscopic anatomy of humans, Vol. 3. Nervous system, skin and sensory organs . Urban and Schwarzenberg, Munich 1985, page 8. ISBN 3-541-00264-6 .
- ^ Robert D Dyson: Cell biology: A molecular approach. Allyn and Bacon, Boston, USA; Page 554. ISBN 0-205-05942-2 .
- ^ Wilhelm Seyffert (Hsg): Textbook of Genetics; 18.6: Separation of the germ line and soma. Gustav Fischer, Stuttgart etc. 1998; Page 417. ISBN 3-437-25610-6 .
- ↑ Viktor Schwartz: Comparative history of the development of animals. Georg Thieme, Stuttgart 1973; Page 53. ISBN 3-13-499901-3 .
- ↑ Volker Storch, Ulrich Welsch, Michael Wink: Evolutionary Biology. Springer, Berlin, Heidelberg, etc. 2001. Page 211. ISBN 3-540-41880-6 .