Eutely

The cell constant or Eutelie is called the biological phenomenon that some organisms or organs have a well-defined, fixed number of cells.

Especially for nematodes ( Nematoda ), the cell constant is frequently detected. Thus, each of the species Caenorhabditis elegans hermaphrodite of exactly 959 cells, as John E. Sulston and other researchers have demonstrated since 1977. First, in the ontogenesis 1090 cells are formed, of which, however 131 cells a programmed cell death to die. In the meantime, in this way, each cell has its specific name. The development of each cell can be accurately predicted or traced. Therefore, this type is particularly important as a model organism for studying the genetic basis of development and gene regulation.

However Eutelie occurs not only in nematodes, they can also be found in some tardigrades, rotifers, and other small invertebrates.

Eutelie has significant consequences for the respective creatures. Thus, the ability to regenerate is greatly reduced, so that even minor injuries can lead to death. On the other hand, cancer tumors are largely impossible, because the cells have lost their ability to divide.

• Cell Biology