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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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MICROBIOLOGY- HISTORY AND DISCOVERY

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HISTORY OF MICROBIOLOGY The history of microbiology ks divided into four eras.   a) Discovery era b) Transition era c) Golden era  d) Modern era a) DISCOVERY ERA      In this era the following scientists have contribution for the discovery of microorganisms.  1. Aristotle.  - he proposed the theory of spontaneous generation.  The Greek philosopher Aristotle (384–322 BC) was one of the earliest recorded scholars to articulate the theory of spontaneous generation.it says that, the notion that life can arise from nonliving matter. Aristotle proposed that life arose from nonliving material if the material contained pneuma (“vital heat”).   2.Rogan -bacon He described that disease caused by the non living creatures ie a minute germ or seed.  3.Antony van Leeuwenhoek.  He is known as the father of microbiology, bacteriology and Protozoology.  -this era was totally dominate by him  . He was the person, who first seen the microorganisms by a simple microscope of single lens of his own design. 
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Cell structure and cell wall of algae notes

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CELL STRUCTURE  CELL WALL FLAGELLA CELL STRUCTURE   On the basis of their organization algal cell maybe differentiate into prokaryotic, mesokaryotic, and Eukaryotic. Prokaryotic are primitive found in Cyanophycean algae characterised by absence of membrane bound organelles, absence of basic protein called histones in DNA.                A Eukaryotic cell have a well organized nucleus and membrane bound organelles.                Mesokaryotic cell has a nuclear membrane and chromosomes(Eukaryotic characters), basic proteins are absent and nucleus division like prokaryotic type (prokaryotic characters). Fou8 in members of Dynophyceae.  1.CELL WALL       Most of the non motile unicellular and multicellular algae possess a typical cellulosic cell wall of non living matter out side the cytoplasmic membrane. It composed of pure or mixed carbohydrate ( cellulose, mucilage, pectin etc.) and substances like alginic acids, fucoidin,, fucin and hemicellulose are present in brown algae
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