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 u...
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Smith system of classification of algae

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Smith system of classification   


    The classification of algae proposed by Smith 1933,51,55) is based on the physiological characteristics of vegetative cells and morphology of motile reproductive cells. 
       He divided algae into seven division and their related classes were included in each division. The seven division of algae recognised by Smith are as follows. 

DIVISION 1.CHLOROPHYTA
Includes 6,750 species, chl a, b are dominant pigment, reserve food start, motile reproductive cells are usually bi-quadriflagllate whiplash types flagella and insertion anterior. 
       Divided into two classes
1.Chlorophyceae(BGA) 
2.Charophyceae(stone worts eg. Chara) 

DIVISION 2.EUGLENOPHYTA
 450 species, dominant pigment chl a, b and beta-carotene , reserve food paramylum and and fats, flagella maybe uni-bi or triflagellate, multiplication usual by cell division. Divided into only one classes. 

1.euglenophyceaeeuglenoids) 

DIVISION 3.PYRROPHYTA
1,030 species, mainly unicellular, pigments chl a, c, beta- carotene and xanthophyll, reserve price starch or oils, Cellulosic cell wall, motile cells are usually with two unlike flagella, sexual reproduction is rarely present. Divided into two classes. 

1.desmophyceae(dinophysids eg. Exuviaella) 
2dinophyceae(dinoflagelloloids) 

DIVISION 4.CHRYSOPHYTA
More than 6000 species,dominant pigment carotenes and xanthophylls,reserve food leucosin and oils, the cell wall is usually composed of two overlapping specified halves., sexual reproduction is iso-,aniso- or Oogamous. David into three classes. 

1. Chrysophyceae (golden- brown algae eg. Chromulina) 
2.Xanthophyceae( yello+ green algae eg. Botrydium) 
3. Bacillariophyceae ( diatoms eg. Pinnilaria) 

DIVISION 5.PHAEOPHYTA(brown algae) 
1000 species, mostly marine, dominant pigments are laminarin(polysachhaeides) and manitol(also) , cellulosic cell wall with fucinic and alginic acids, motile reproductive cells are pyriform With two laterally inserted flagella, one of which is tinsel type, sexual reproduction is iso-, aniso-, or Oogamous. Divided into three classes. 

1.isogeneratae(eg ectocarpous) 
2.hetero-generatae (eg. Laminaria) 
3.cyclosporeae( fucus) 

DIVISION 6.CYANOPHYTA (BGA) 
1500 species, mostly fresh water, some are free living, while others grow on other algae or with in the tissue of other algae. The cell is prokaryote type. In addition to other pigments, they contain a blue (c- phycocyanin) and red(c- phycoerythrin) pigments. Reserve food in the form of Chan starch. Motile stages are absent but  vegetative filaments  of some forms show gliding movements. Sexual reproduction is absent., asexual reproduction takes place by hormonia, fragmentation andakinetes etc.

Placed in a single class , Myxophyceae or  Cyanophyceae eg nostoc, anabaena etc. 

DIVISION 7.RHODOPHYTA(Red algae) 
  2500 species, mostly marine, predominant pigment r- phycoerythrin which mask the other pigments to give a red colour. Reserve price is in the form of floridean starch. Thallus is nonmotile and complex. Sexual reproduction is Oogamous, motile reproductive cells are not found. 

Placed in a single class Rhodophyceae. Eg., Gracillaria, Polysiphonia etc etc. 




😃😃😃😃.......... 








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