Eyelashes and zhgutik

These are the special organellas of the movement which are found in some cages of various organisms. In a light microscope these structures look as thin outgrowths of a cage. In the basis of eyelashes (cilium) and a zhgutika of flagellum) in cytoplasm well painted small granules — bazalny little bodies (corpusculum basale) are visible. Length of eyelashes of 5 — 10 microns, and length of zhgutik can reach 150 microns (see fig. 43, V).

The eyelash represents a thin cylindrical outgrowth of cytoplasm with a constant diameter of 200 nanometers. This outgrowth from the basis to its top is covered with a plasmatic membrane. In an outgrowth the aksonema ("an axial thread") — the difficult structure consisting generally of microtubules is located. The proximal part of an eyelash (a bazalny body) is shipped in cytoplasm. Diameters of an aksonema and bazalny little body are identical (about 150 nanometers).

Other fibrillyarny structures of cytoplasm.Except microtubules, mikrofilament (microfilamenti) 5 — 7 nanometers thick and so-called intermediate filament, or microfibrilla (microfibrillae) belong to fibrillyarny components of cytoplasm of eukaryotic cells, about 10 nanometers thick.

Mikrofilamentameet practically in all types of cages. On a structure and functions they happen different, however from each other difficultly to distinguish them morphologically. Mikrofilament in a kortikalny layer of cytoplasm, directly under plazmolemmy, bunches or layers settle down. It is possible to see them in the psevdopodiyakh of amoebas or in moving shoots of fibroblast, in microfibers of an intestinal epithelium. Mikrofilamenta often form the bunches going to cellular shoots.

The network of mikrofilament is revealed in the majority of cages. They differ on a chemical composition. Depending on their chemical composition they can carry out functions of a cytoskeleton and participate in ensuring the movement. This network — part of a cytoskeleton. By means of immunofluorescent methods it is accurately shown that the structure of mikrofilament of a kortikalny layer and bunches includes sokratitelny proteins: актин, myosin, тропомиозин, and-aktinin. Therefore, mikrofilament no other than the intracellular sokratitelny device providing not only mobility of cages at their active ameboidny movement, but probably and the majority of intracellular movements, such as cytoplasm currents, the movement by a vacuole, mitochondrions, cell division.

Intermediate filament,or microfibrilla, too proteinaceous structures. These are thin (10 nanometers) the threads which aren't branching, often settling down bunches. It is characteristic that their proteinaceous structure is various in different fabrics. In an epithelium, for example, the keratin is a part of intermediate filament. Bunches of keratin intermediate filament in the epitelialnykh cages form so-called tonofibrilla which approach desmosomes. The structure of intermediate filament of cells of mesenchymal fabrics (for example, fibroblast) includes other protein — виментин. For muscular cages protein десмин is characteristic, in nervous cages special protein also is a part of their neyrofilament.

Recently by means of immunomorphological methods became possible to determine a fabric origin of these or those tumors by proteins of their intermediate filament that is very important for a right choice like chemotherapeutic antineoplastic preparations.

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