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. 
- he called the microorganisms  animaculus. 


b) Transition era

1.Francesco Redi
Who showed that flies meggots don't arise from decaying meat (as other believe) if the meat is covered to prevent the entry of flies. 


2. John Needham. 
Supported spontaneous generation theory,  proposed that tiny organisms arose spontaneous from motton gravy. He heated the flask and and open the flask, then meggots grew on motton. 


3.Lazzaro Spallanzani. 
He described that boiled motton broth would not giving rise microscopic form of life.he heated the flask and open  the cork to remove air and again heated then sealed it and seen that mango were not arising on motton gravy. But when open the flask mega arose to grow. 


.

c) GOLDEN ERA
1.Louis pasteur
Known as father of medical microbiology. Gave pasteurization process(the partial sterilization of a product, such as milk or wine, to make it safe for consumption and improve its keeping quality.). Also gave fermentation and development of vaccines (Rabbies  and Anthrax). Demonstrate the disease of silkworm cause due to a protozoan parasite. Coins the term microbiology, anaerobic, aerobic. Disproved spontaneous generation theory by sean naked shaped apparatus experiment. 


Pasteur conducted an experiment in which he used a glass flask with an S shaped neck, This he explained was because the germ particles in the air attempting to enter the flask had become became trapped in the s shaped bend. Therefore, they had not contaminated the liquid.

2. John Tyndall

Discover highly resistant bacterial structures later known as Endospore. 
- gave Tyndallisation process (Sterilization of a fluid by heating it repeatedly to a point slightly below that of boiling. With each heating the bacteria which have developed from the more resistant spores are destroyed; when finally no undeveloped spores remain the fluid is sterile.) 

3. Lord Joseph Lister

-father of antiseptic surgery. 
-concluded that wound infections too were due to microorganisms. -he also discover a process to destroy might in the operation theatre by spraying a fine chemical called carboxylic acid in air to sterilized the theater. 

4.Robert  Koch




He demonstrate the role of back in disease causing. 
-he perfected the techniques of isolation of bacteria in pure culture. 
-he used gelatin to prepare the media but it was not ideal. Because, i) since gelatin is protein, it is digested by many bacteria capable of producing gelatinase that Hydrolise the protein to amino acids. b) it melting when temperatures rise above 25degree celsius. - he first isolated Anthrax. 

5.Fanne Eilshemius Hesse

First proposed the use of agar in culture media. It was no attacked by most bacteria. 
- agar is better than gelatin because of kts higher melting points and solids point. 

6. Edward Jeener
First to prevent small -pox. Discovery of techniques of vaccination. 

7.Alexander Flemming
Discovery of Penicili from penicilium notatum that destroy several pathogens bacteria. 

d) MODERN ERA
Nobel laureates year or nobel laureates contribution
-1901-VonBehring Dipth- antitoxin
-1902-Ronald Ross- malaria
-1905-Robert koch-TB
-1908-Metchnikoff-phagocytosis
-1945-Flemming-penicilin
-1962-Watson and Crick-strucrure of DNA
-1997-Khorana-genetic code. 


    "ALL WE HAVE IS NOW"😃😃😃😃😃😃

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