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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Fritsch system of classification of algae Chlorophyceae,xanthophyce and bacillariophyceae , notes

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Fritsch system of classification


      The most effective classification of algae was given birth F.E Fritsch (1935,48)  in his book " The structure and Reproduction of Algae" . This classification based on such criteria as pigmentation, types of flagella, assimilatory products, thallus structures and reproduction. He divided algae into the following eleven classes. 


1. Chlorophyceae ( grass green) - nine orgers. 
2.Xanthophyceae( yellow  green) - four orders. 
3.Chrysophyceae( brown or Orange) - three orders. 
4.Bacillariophyceae(diatoms, yellow or golden- brown) two orders. 
5.Cryptophyceae( nearly brown) two orders. 
6.Dinophyceae( dark yellow or brown) six orders. 
7.Chloromonadineae( Bright green) single order. 
8.Euglenineae( pure green ) three orders. 
9.Phaeophyceae( brown) nine orders. 
10.Rhodophyceae ( red) seven orders. 
11.Myxophyceae or Cyanophyceae ( GGA) five orders. 

1.CHLOROPHYCEAE(isokontae, green algae) 

     The Main pigments identical to that of higher plants. That are chl a, b, Carotenoids and xanthophylls. The chloroplast contains pyrenoids. Reserve food is starch  , which aggregate around the pyrenoids. Cell wall is cellulosic, cells are typically Eukaryotic. Flagella, if present are equal length and at the anterior end. Reproduction is by vegetative, asexual and sexual (iso-, aniso-, Oogamous) methods. 
          This class has been divided into fall nine orders. 
i. Volvocales ( eg. Volvox) 
ii. Chlorococcales, eg. Chlorella
iii. Ulotrichalea, eg. Ulothrix
iv. Cladophorales, eg Cladophora
v. Chaetophorales, eg Fritschiella
vi. Oedogoniales, eg Oedogonium
vii. Conjugales, eg Zygnema
viii. Siphonales, eg Vaucheria  and
ix. Charales, eg Chara. 

2.XANTHOPHYCEAAE (  heterokont, yellow green algae) 

        The main pigments are chl a, e, beta- carotene and xanthophylls. The plastids are with out pyrenoids and reserve food is oil. Cell wall composed of pectic substances With little bit of cellulose. Cell is typically Eukaryotic with two anterior inserted unequal flagella the shorter flagellum is whiplash type and longer is tinsel type. Reproduction by vegetative, asexual and sexual  (Isogamous)  methods. 

      This class have been divided into following four
 orders. 
i. Heterochloridales, eg Heterochloris
ii. Heterococcales,  eg  Halosphaera
iii Heterotrichales, eg  Microspora
iv Heterosiphonales, eg  Botrydium. 

3. CHRYSOPHYCEAE

      Phycochrysin is dominant pigment which imparts brown or orange colour. The Chromatophore (is a cell containing pigments and hence reflects light. )  happy naked pyrenoids- like bodies reserve food is chrysolaminarin and leucosin. Cell wall is silicified or calcified and non cellulosic. The motile call have two Anteriorly inserted unequal or equal flagella. Sexual reproduction is rare, when present its Isogamous. 

      This class includes three orders. 
i. Chrysomonadales, eg Chrysococcus
ii. Chrysosphaerales, eg Chrysosphaera
iii. Chrysotrichales, eg chrysoclonium. 

All the best...

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