Economical importance of bryophytes

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ECOLOGICAL IMPORTANCE OF BRYOPHYTES Mosses and Bryophytes are the first organiasms to colonise rocks. They colonise rock by acidic secretion. This acidic secretion is due to the death of mosses. When the rock is decomposed it helps in soil formation. Therefore New soils are formed. The soil act as binders.  It prevent soil erosion. The water retention capacity of the soil is high ie, water holding capacity of the soil is high.  This reduces surface water run-off which prevent soil erosion. Bryophyte helps in the recycling of nutrients. ECONOMICAL IMPORTANCE OF BRYOPHYTES. 1) SPHAGNUM Sphagnum has high absorptive power with antiseptic property. This can be used to replace cotton in bandages. 2) MERCHANTIA   Mercahntia cures pulmonary tuberculosisand affliction (pain) in liver. Antibiotic substances are also extracted from bryophytes. it also acts as antiseptic, and as preservative POLYTRICHUM Polytrichum dissolove stone in kidney and in gall bladder. 3) IN RESEARCH It is used in the fie
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There domain classification of organisms ( archaea, bacteria and eukarya) , notes

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       Till recently, in living organisms two types of classification were recognized, prokaryotic cell with no organised nucleus and eukaryotic cell having organised nucleus and an nuclear envelope. Bacteria and blue green algae were included in prokaryotic cell and higher organisers were included in eukaryotic cell. However, another group of prokaryotic cells archaea were discovered in 1977 , so that the prokaryotic cells could be divided into Archaebacteria and eubacteria. It was shown that the group archna is distinct from bacteria and eukaryotes. As a result the living organisms now divided into three domains ie., bacteria, archaea and eukarya. 

     Such a classification in three domains has been proved in the recent year 1996 , when the genome of an archaeon, namely Methanococcus jannaschii( during the expedition to deep sea  M. Jannaschii was discovered in 1982 from a hot spot beneath the pacific ocean and was found to be methane producing organisms) . It's nucletide sequence is fully compared with sequences of genome of bacteria and eukaryotes. 

    Flowing are some of novel features of archaea forcing biologist to place it in a new domain archaea which is distinct from bacteria and eukarya. 

In archaea, the distribution of eukaryotic, prokaryotic and novel unique genes  mentioned below. 

1. It lives at temperatures ranging from 48-94°  C and at pressure of more than 200 atmospheres, some archaea lives at salt concentration upto 10 times higher than that of sea water. 
2. Oxygen kills it. 
3.it is an autotrophs utilizing carbon dioxide, nitrogen and hydrogen, it produces methane thus is a methanogen. 
4..there are genome in this archeon, that resemble those of bacteria and other resemble eukaryotes and some other that still completely new to science..
 
        It has been shown that the archeal system is more like to eukaryotic system. In facts scientists now believe that the common ancestor of all modern living life was a thermophile ( heat loving) after the earth has formed . Which blanched off more than 3.6 billion years ago into three major life forms ie., bacteria ( peokaryotes) , archaea and eukarya. 

All the best....


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