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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Mutations

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                         Mutation

** 1st reported by Seth wright in lamb with extremely short legs.
** Mutations also called as Saltation and saltatory variations by Bateson.Also called as Sports by Darwin.
** Explained by : Hugo de Vries experimented on Oenothera   lamarckina.
**Mutation are sudden, discontinuous ,inheritable(heritable) variations in the phenotype,due to alteration in DNA or genes or chromosomes.
Types of mutation:
On basis of occurence: Spontaneous and induced.
On basis of type of cell in which they occur : Somatic and Germinal
On basis of type of allele formed : Forward and Backward

On basis of cause of mutation: 3 type
1)Gene mutation
2)Chromosomal mutation
3)Genomatic mutation

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