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 haplontic and diplobiontic life cycle , notes

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Life cycle of algae

   The growth and development of alga passes through a number of distinct morphological and cytological changes or stages. the sequence of these orderly changes is said to be life cycle or like history of algae.   
              Ie., It's from one zygote generation to the next orr one gametophytic generation to the next is said to be life cycle.

Haplontic life cycle.

     The plant body is haploid bears haploid gametes in the gametagoniun . the gametes are fused and form a diploid zygote , which is only the diploid stage or phage during their life cycle. Later the zygote nucleus divides meiotically and form four haploid meiospore . Each meiospore develops into new individuals .this there is alternation of the haploid gamete with diploid zygote.
    Here gametophytic generation is dominant over sporophytic generation.   Found in motile unicellular form ex., Chlymadomonas, Oedogonium,Volvox ,Chara etc.

Diplontic life cycle.

      Diploid plant body bears diploid sex organs , reduction division takes place in these sex organs at the time of gamete formation,after gamete fusion the diploid stage is re-establish in the form of zygote.the zygote gives rise to a diploid plant body.  Only the gametes represent the haploid stage during the life cycle.thus there is an altercation of generation of diploid zygote with haploid gametes.
    Here sporophytic generation is dominant over gametophytic generation.fiund in some members of chlorophyceae ( cladophora etc) ,phaeophyceae( fucus etc) and nearly all bacillariophyceae.

All the best....

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