Dunaliella salina - Overview

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                 Dunaliella salina Dunaliella salina is a unicellular microalgae belong to division Chlorophyta . It is found in salinity environments such as salted brines, salt evaporation ponds, and hypersaline lakes  .It is able to tolerate varying NaCl concentrations, ranging from 0.2% to approximately 35% . Thus, Dunaliella salina is a hyper-halotolerant organism found in high densities in saline lakes.  The ability to tolerate high salt concentrations is advantageous, since competition is minimal in high salt concentration areas.  How D.salina   tolerate high salt concentration? D. salina has adapted to survive in high salinity environments by accumulating glycerol to balance osmotic pressure. Note :  D. salina is also adapted to solar radiation using β-carotene to protect against ionizing energy.                 Red Colour of Salt Brines  Dunaliella salina...
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What is cleavage ?

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Cleavage:  It is rapid mitotic cell division that converts unicellular zygote into multicellular blastula ot blastocyst.

Significance of cleavage:
**Distribution of the cytoplasm of zygote amongst the blastomeres.
**Increase mobility of protoplasm which faciliate morphogenetic movement,germ layer formation and formation of tissues 
**Restoration of cell size and nucleocytoplasmic ratio.


Difference between mitosis and cleavage:

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