The Structure Of Unicells Does Not Provide Reliable

The structure of unicells does not provide reliable protection at considerable changes of an environment. Accordingly at monocelled the major form of adaptation is variability. Accustoming of microorganisms is based on this property to toxic substances, in particular to antibiotics. If it is possible so to be expressed, the monocelled individualities not allocated with the same degree as higher organisms, adapt at the expense of change of the individuality or by change of properties of all population of organisms at the expense of acquisition of new properties (for example, stability to an antibiotic). On the contrary, at higher organisms individuality preservation is provided with special protective mechanisms that corresponds to a principle of preservation of a homeostasis. These mechanisms carry out the changes necessary for protection, but ability of an organism thus remains again to return to an initial condition when necessity for protection disappears. Though adaptation to damaging factors is carried out at all levels of systems of an organism, since cellular, however for realisation protective reaction at ' higher organisms there is a specialised adaptable system, or adaptable .