DISPUTES

From Big Medical Encyclopedia

DISPUTES (Greek spora sowing, crops) — the microscopic rudiments formed by nek-ry plants and bacteria at asexual reproduction.

Disputes of plants

S. form plants of various systematic groups — seaweed, mushrooms, many types of the highest a plant.

At bacteria (see) S.'s education serves only for survival in unfavorable conditions of the environment. At approach of favorable conditions, including at hit on suitable Wednesday, S. burgeon, giving rise to a vegetative phase of development of an organism.

Fig. 1. Outward dispute of some species of plants: 1 and 2 — Bryophyta (1 — Fossombronia angulosa, 2 — Anthoceros tuberculatus); 3, 4 and 5 — ravnospory pteridophytes (3 — Pteridium aquilinum, 4 — Lycopodium clavatum; 5 — Dryopteris filixmas); 6 and 7 — raznospory pteridophytes (6 — Salvinia cucullata, 7 — Selaginella radiata).

Pages have a protective shell of complex structure, a necessary reserve of nutrients, are capable to keep viability long. In a form C. happen spherical, ellipsoidal, rhabdoid (bacillary form) etc. (fig. 1). They can be formed is endogenous — inside sporovmestilishch or is exogenous — in special spore-forming body, can be motionless (aplanospores) and actively mobile, flagellar (zoospores).

On a way of education of S. divide into 3 groups: The pages formed without preliminary meiosis, usually with unary haploid less often with diploid kernels, or dicaryons (i.e. mitospor); The Pages formed at a gametic syngamy (e.g., oospores of seaweed, oomycetes); the haploid S. formed at meiosis or meyosior (aplano-and zoospores of cabbage-weeds, zoospores and tetrasior brown and lavers, aflagellar S. of miksomitset, asko-and basidiospores of mushrooms, S. of the higher plants). At the higher plants of S. are formed by the fours (tetrads) of arkhesporialny cells. At mossy, plaunovidny, hvoshchevidny and pteroid S. are sown, forming haploid gametogophytes (prothalliums). Ravnosporovy ferns form identical S.; at raznosporovy ferns and spermaphytes also megaspores form micro; from a microdispute develop men's, from megaspores — female prothalliums.

S. extend or it is active, by means of flagellums (a zoospore of seaweed and nek-ry mushrooms), or is passive — with the current water, air currents or by means of insects and other animals.

The pages of mold and nek-ry other mushrooms which are present sometimes at air in large numbers can serve as the reason of allergic diseases. At nek-ry parasitic protozoa (see. Sporozoa ) in a life cycle of their development the stage of a sporogony (development of a zygote) takes place, on an extent the cut occurs education a dispute, the unfavorable conditions serving for experience.

Disputes of bacteria

Fig. 2. The diagrammatic representation of the rhabdoid bacteria containing endospores (formations of an oval form on one of poles of each bacterial cell).

Disputes of bacteria — a special form of existence of nek-ry species of bacteria. Ability to education a dispute (endospores) preferential rhabdoid bacteria (fig. 2) have. Sporogenesis at bacteria happens at their hit in unfavorable conditions of the environment and is means of preservation of a look in conditions under which reproduction of a bacterium and preservation by vegetative forms of viability is impossible.

S.'s resistance of bacteria to influence of various volumetric and physical factors is very big. So, S. of nek-ry bacteria do not perish at long boiling or influence of various disinfecting substances. In particular, the possibility of long preservation a dispute in 96% alcohol was noted. In S.'s soil can be without changes for many years.

S.'s education begins with emergence in the vegetative cell prosior representing the condensed site which is strongly refracting light and painted more intensively than all cell. Then this site takes the round or oval form and ceases to be painted, standing apart from other cell a dense cover. After such mature S.'s education the body of a vegetative cell dies off. As a rule, in a bacterial cell no more than one Page are formed.

Fig. 4. Bacillus cereus pure growth; are visible painted in crimson color it is central the located disputes and vegetative forms painted in blue color; coloring across Auyeske; X 800. Fig. 5. Clostridium botulinum pure growth; shooters specified subterminalno the located disputes; coloring across Gram; X 800. Fig. 6. Clostridium perfringens pure growth: 1 — subterminalno the located disputes; 2 — it is central the located disputes (the mixed arrangement a dispute); coloring by carbolic fuchsin and methylene blue; X 800.
Fig. 7. Clostridium tetani pure growth; shooters specified terminalno the located disputes; coloring by carbolic fuchsin and methylene blue; X 800.

Form, size and S.'s arrangement in a cell as well as ability to sporogenesis, are taxonomical signs (tsvetn. fig. 4 — 7). The bacteria forming S. belong to this. To Bacillaceae including five childbirth, two of to-rykh (Bacillus and Clostridium) matter for medicine. From bacteria, pathogenic for the person, to the sort Bacillus activators of a malignant anthrax (see), belong to the sort Clostridium — activators tetanus (see), botulism (see), gas gangrene (see. Mephitic gangrene ). Epidemiol. bacterial S.' value is defined by a possibility of their long preservation in the soil (disputes of causative agents of tetanus, gas gangrene, a malignant anthrax), and also in badly sterilized canned food and other foodstuff (the causative agent of botulism).

High resistance of S. of bacteria to various influences is connected with existence at them a dense multilayer cover, low water content, lack of enzymatic activity. To factors, about uslovlivayushchy high stability of S., the calcic salt which is also contained in them dipikolinvy to - you belongs (calcium in disputes much more, than in vegetative bodies of the same bacteria).

For S.'s coloring use the special methods providing a preliminary loosening of a cover various pickles and influence of high temperature. One of the most widespread ways of coloring of S. is Auyeski's method. By this method the smear of sporuliruyushchy culture is dried up on air, process 0,5% solution salt to - you, dry again, and then painted during the heating by carbolic fuchsin of Tsil, immerse for decolouration in 5% sulphuric acid solution, washed out, again painted methylene blue on Lefflera, washed out and dried. Pages are painted in red color, bacterial bodies — in blue. M. A. Peshkov offered simpler method of coloring: the fixed smear is processed methylene blue (on Lefflera), then water solution of neutral red, washed out a distilled water and dried up. Mature S. are painted in blue or blue color, young S. — in black-blue, prosior — in violet-blue; cytoplasm of vegetative forms has pink coloring, chromatinic elements of cytoplasm — violet. Villages find also by means of phase-contrast microscopy after adsorption of dye on S. Sushchestvuyut's surfaces and methods of detection of S. of bacteria by means of luminescent microscopy.

Fig. 3. Diagrammatic representation of a structure disputes of bacteria: 1 — a core disputes; 2 — nuclear material; 3 — a plasma membrane; 4 — a cortical layer; 5 — a multilayer cover; 6 — cytoplasm of a mother cell.

S.'s structure of bacteria was studied by means of a submicroscopy most in detail. At a research ultratonkrkh cuts it was shown that mature S. consist (fig. 3) of the «core» containing nuclear material, the cortical layer surrounding it consisting of a peptidoglikan, and a multilayer cover. So, covers dispute you. cereus consist of three layers, you. megatherium — from two. More detailed studying of a cover of S. showed that it has a lamellar structure. This feature, apparently, also plays a large role in high stability of S. of bacteria.

See also Sporous aerobes .



Bibliography: Willie K. A. and Detye V. D. Biology (Biological processes and laws), the lane with English, page 267, 660, M., 1974; Life of plants, under the editorship of A. A. Fedorov, t. 1 — 4, M., 1974 — 1978; Korn M. Ya. and Solov-e in H. H. About use of fazovokontrastny microscopy for observation a dispute in the painted smears, Laborat. business, No. 6, page 51, 1961; Short determinant of bacteria of Bergi, under the editorship of J. Hoult, the lane with English, page 286, M., 1980; Works N about in and I. L. General microbiology, page 65, M., 1966; The Guide to microbiological diagnosis of infectious diseases, under the editorship of K. I. Matveev, page 27, M., 1973; Steyniyer R., E d e l e r E. and Ingram D. The world of microbes, the lane with English, t. 3, page 184, M., 1979; The bacterial spore, ed. by G. W. Gould a. A. Hurst, L. — N. Y., 1969.


T. V. Veshchikova; M. Ya. Korn (bakt.); M. Ya. Korn and M. F. Kultayev (tsvetn. fig.).

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