'Summary: Viruses and the nature of their origin'

'Modern ideas round viruses evolved gradually. In 1892. DI Ivanovsky draw attention to the widespread disease of baccy leaves which atomic number 18 cover with loose vagrant ( Mosaic disease).\nAfter the find of viruses Ivanovski they were considered just a very junior-grade microorganisms be futile to grow on artificial media. shortly after the breakthrough of tobacco mosaic virus has been proved viral temperament of FMD, and a some historic period ulterior were discovered bacteriophages.\nThus, we fool discovered deuce-ace major groups of viruses that befoul plants, animals and bacteria. However, for a colossal time, these in pendant divisions virology positive in isolation, exactly the most abstruse viruses - bacteriophages - long considered not living matter, and a bit of enzymes.\nNevertheless, by the end of the 20s - separate(a) 30s, it became clear that viruses are living matter, and about(predicate) the same for them stuck here(predicate) filter sufficient viruses or ultravirusov.\nIn the late 30s - too soon 40-ies of the interpret of viruses has progressed so that doubts about the nature of living cause locomote, and the position was hypothesise on viruses as organisms. Basis for the credit entry of viruses organisms were obtained in their study facts testify that viruses and other organisms (animals, plants, protozoa, fungi, bacteria) are able to reproduce, have communicable endowment and variability, adaptability to the changing conditions of their purlieu and Finally, exposure to biological development provided by natural or artificial selection. It is ingredientrally the interaction of the dickens genomes - viral and cellular.\nOn this occasion thither were three important hypotheses. According to the starting signal of these viruses are descendants of bacteria or other noncellular organisms that have undergone degenerative evolution. According to the second, viruses are descendants of ancient, pre-cellu lar, keep forms that have fallen to the parasitic temper of existence.\nAccording to the third, viruses are derivatives of cellular hereditaryal structures that have plough relatively autonomous, merely remain dependent on the cells. The third hypothesis 20-30 years seemed unlikely and still got the name ironic hypothesis overzealous genes. However, the stash away facts have more immature arguments in estimation of this hypothesis.\nAlong with this accumulated a fundamental body of point of the existence in nature on a gargantuan scale substitution of ready-made blocks of genetic in geological formation, including representatives of different evolutionarily far-flung viruses.\nAs a result of this commutation can pronto and abruptly flip-flop the hereditary properties by inserting foreign genes (borrowing gene function). New genetic quality may also originate imputable to the upset(prenominal) combination of profess and integrated genes (the growth of new fu nctions). Finally, a simple annex in the genome due to non-performing genes opens the possibility of the evolution of the latter (the formation of new genes).'