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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Factors determine Cell shape, size and number, notes

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1. Cell shape
     There is a great amount of variability in cells with respect to cell shape. Some cells are like amoeba and leukocytes change their shape frequently. Other cells have a typical shape. Some bacteria are rods, spirals, and even comas. Some algae like diatoms and desmids have different shapes. 
       In multicellular organisms the cell is shape is partly controlled by the pressure the cell exert against each other so that when isolated in a liquid these cells may become spherical according to the law of surface tension. In this way, leukocytes are spherical in  circulating blood, but may become irregular in shape in other conditions. Cell shape also depends upon the functions as they has to perform. For instance, cell like glandular hairs on a leaf, the guard cell on stomata, and root hair cells have their special shapes. Stability to the cell shape is provided by the association of the cytoskeleton with the inner surface of plasma membrane Of the cell. 

2. Cell size
      Cell size diameter varies greatly in various plants, animals and microorganisms. It is varies from the smallest cell mycoplasma to the largest cell ie., the egg of Ostrich. The smallest cell ranges from 0.1- 0.3 micro meter,6 inches in diameter. The bacteriophages and viruses are still smaller in size, but they are not considered to be cellular in their organization. 

        The cell size also depends in many cases on the size and numbers of Chromosomes. In many cases it has been proved that when the chromosome number is artificially doubled, the cell size automatically increased.
 The cell size is also decided by the following factors ie., 
1.Nucleocytoplasmic ratio ( the nucleus should be capable to control and take care of all the functions of the cell completely.) 
2.surfacse area to volume ratio..
3.rate of metabolism. 
       
With Increase in the cell size surface area to volume ratio gradually decreases for the exchange of materials with increase in volume may not be available, then the metabolic activities of the cell will be decreased. So to maintain the ratio higher the cell size should be smaller. 
  In general the cell volume is constant for a cell type and doesn't depends on the organism. For instance, kidney cells in bull, horse or mouse are Same in size and the difference in size of the organisms depends on the cell number only. This is sometimes called the law of constant volume. 

3. Cell number
       The cell number in an organism varies from a single cell in a unicellular organism to 60 thousand billion cells in a human being weighting about 80 kg. This number would be more in certain organisms. The number of cells in multicellular organisms is rather indefinite, but it may be fixed in organisms like Pandorina and Eudorina( both green algae) . 
, the former with a colony consisting of 8,16,32,or 64 and the latter with 16,32or 64 cells. 

😃😃😃😃😃😃..... 

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