Tsentrioli

This term was offered T. Boveri in 1895 for designation of very small little bodies which size is on limit of resolution of a light microscope. In some objects it was possible to see that small dense little bodies — tsentriol (centriolum) which are usually located in couple — a so-called diplosom (diplosoma), are surrounded with a zone of lighter cytoplasm from which radially thin fibrilla (a so-called tsentrosfer) depart. Tsentrioly and tsentrosfer call set the cellular center (cytocentrum). These organellas in the sharing cages take part in formation of a spindle of division and settle down on its poles. In the tsentriola cages which aren't sharing (interfaznykh) often define polarity of cages, for example, an epithelium, and settle down near Golgi's complex.

Round each tsentriola it is located unstructured, or fine-fibered, матрикс. It is often possible to find some additional structures connected from a tsentriolyama: satellites (satellites), focuses of a convergence of microtubules, additional microtubules forming a special zone, to a tsentrosfer round a tsentriola.

By preparation of cages for the mitoticto division there is a doubling of the tsentrioly. This process at various objects happens at different times — during synthesis of nuclear DNA or after it.

It is that two tsentriola in a diplosoma disperse and about each of them arises anew on one new affiliated so in a cage before division two diplosoma, i.e. four in pairs connected tsentriol are found. This way of increase in number of the tsentrioly was called duplication. It is important to note that the increase in number of the tsentrioly isn't connected with their division, budding or fragmentation, and occurs by formation of a rudiment, a protsentriola, close and perpendicularly to an initial tsentriola.

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