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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what is Haplodiplontic life cycle ( triphasic)

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Triphasic life cycle.

      In triphasic life cycle there is a succession of there generation ie may be two haploid generations and one diploid generation or one haploid generation with two diploid generations.it is of following types ie ,

 I.Haplobiontic type ( 2 haploid + 1 diploid) 
       In some rhodophyceae like Batrachospermum two well developed haploid phase are present and the diploid phase is represented by only zygote.
        
       The haploid plant body bears sex organs ( spermatogonia, carpogonia ) haploid gametes ( sperm and egg)  are formed in these sex organs,a diploid zygote is formed by the fusion of two gametes.the nucleus of the zygote divides meiotically to form four haploid carpogonia ,  they later develop into carposporophyte  generation ( a haploid generation) . the carposporophyte bears carpospores , after liberation carpospores are germinate into heterogeneous chantransia stage ( resting stage) , after this stage a new gametophytic plant body is formed ( another haploid phase).

ii.  Diplobiontic type( 2 diploid+ 1 haploid) 

      In this type of life cycle, there is an altercation of two diploid phase ( carposporophyte, tetrasporophyte ) alternating with a haploid gametophytic  phase.
        the zygote produce by the fusion of gametes , the zygote develops into gonimoblast which represent the diploid carposporophyte carposporophyte phase.the carposporophyte produce diploid carpospores which germinate to form diploid tetrasporangia ( another diploid phase and tetrasporangia is the sex organs of tetrasporophyte) . four tetraspores( haploid gametes) are formed in tetrasporangium by the reduction division.tetraspores give rise to haploid gametophytic plants which bears haploid male and female gametes.the life cycle is thus completed.

    Found in Polysiphonia( rhodophyceaean algae) .

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