The NO-synthase inhibitor LNNA (2,5 mg/100 g) abolished the protective effects of short-term adaptation to hypoxia (1 hour, 5000 m above sea level) on the development of stress-induced disorders on the model of acoustic stress in the Krushinsky—Molodkina rats genetically predisposed to audiogenic seizures. Using electronic spine resonance method (ESR) we also demonstrated an increase in NO production during short-term hypoxia in the blood and spleen. The results suggest that NO plays a positive role in protective effects of short-term adaptation to hypoxia.

It is shown, that at cultivation hydrobionts in integrated recirculating systems more than twice ecological efficiency of use of food in comparison with a monoculture raises. The highest biological production and more effective utilization of the assimilated food are observed in conditions variable temperatures.

Trichomes present on the leaf surface of both intact and in vitro Stevia plants (Stevia rebaudiana Bertoni) were examined using scanning and transmission electron microscopy. Three types of trichomes were observed both on adaxial and on abaxial surface of leaves: (a) spherical glands, (b) large hairs, (c) small hairs. The trichomes appeared in higher numbers on the leaf surfaces of the intact plants. The numbers of trichomes seem to be greater on the upper leaves than on the lower leaves. The results of the work provide evidence for positive correlation between number of glands on leaves and their content of the SGs. Three major stages in the development of the gland cells were identified, corresponding to the stages of secret accumulation.

The paper presents the results of studies of epilithic phototrophic microorganisms colonization on CaCO3-containing samples (cubes of a chalk) in the nutrient medium with different concentrations of cupreous and plumbic salts. The fluorescens pulse amplitude modulation as well as the amperometric technique were used to control the action of Cu2+ and Pb2+ on the photosynthetic activity of enrichment cultures isolated from limestone of the Archangelskoe estate-museum historical buildings (XVIII—XIX c.).

The bottom sediments decreased the toxicity of inorganic (sodium dichromate and copper chloride) and organic (imazalil sulphate) compounds for cladocera Daphnia magna. The effect of sodium dichromate at the survival and fecundity of crustaceans most of all was reduced by silt and loam, containing clay and high level of organic substances. The toxicity of copper chloride was decreased not only by silt and loam, but also by sandy loam with low content of clay and organics. The sandy loam was most effective in decreasing of imazalil’s toxicity at the survival of crustaceans.

By means of determination analysis data optimum values of phytoplankton biomass and its divisions are calculated. These values provide development of high biomass such primary consumers as zooplankters. It is shown, that representatives of Rotatoria have higher levels of optimum biomass, than Crustacea. In Kara region it is possible to ascertain the increase such levels for Cladocera in comparison with Copepoda. The prediction of zooplankton communities development is carried out using values of optimum biomass of phytoplankton. Accuracy of the forecast in the Azov area is highest, i.e. quantitative requirements of zooplankton for fodder phytoplankton here are poorly subject to variability in time.

We studied external morphology and molecular genetics of two forms of the Oriental Fire-Bellied Toad, described as subspecies Bombina orientalis silvatica Korotkov, 1972 and Bombina orientalis praticola Korotkov, 1972. We have found significant differences between them in body size, coloration and some morphometric parameters but not in genetics. Taking into account their geographical separation, one can consider them as forest and meadow ecological morphs but not different taxa. Therefore, the names Bombina orientalis praticola Korotkov, 1972 and B. orientalis silvatica Korotkov, 1972 should be considered as junior synonyms of the name Bombina orientalis (Boulenger, 1890). We suppose that these morphs have been isolated from each other recently, and their morphological differences at genetic similarity are related to high plasticity of the species, when ecologically determined morphological differentiation precedes genetic differentiation.

Results of the study on external morphology of five deepwater skates from the North Atlan-tic (Amblyraja jenseni, Bathyraja pallida, B. richardsoni, Rajella bigelowi, R. kukujevi) conducted in various museums showed that their males and females significantly differ in 9 characters in first species, 14 — in second species, by 11 — in third and fourth species, and 10 — in latter species. Sexual differences occur most frequently in the length of 1st gill slit (4 of 5 species), length of nasal curtain, mouth width, and length of 3rd gill slit (3 of 5), disc width, lengths of 1st and 2nd dorsal fin bases, length of 5th gill slit, spaces between 1st and 5th gill slits, interspiracular width, distance between snout and center of anus, distance between snout and maximum disc width, interorbital width (2 of 5).