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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Gram Positive vs Gram Negative

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Major Differences Between Gram Postive and Gram Negative Bacteria

STAINING IN BACTERIA:
Given by Christain Gram.
He used Crystal Violet/Christian Blue/Gram stain  .


Frequently Asked Questions:

Ques-Which is more harmful Gram +ve ir Gram -?
Ans-Gram negative bacteria is more harmful and causes diseases.Because  a slime layer is present outside their outer membrane which hides the antigen present in it.

Ques-Is it easier to kill Gram +ve bacteria?
Ans-Cell wall of gram positive bacteria easily absorbs absorb antibiotic and cleaning products.Hence, they are easier to kill.

Ques-What infections are caused by  gram +ve bacteria?
Ans-Gram +ve bacteria cause usually yrinary tract infections.

Ques-What infections are caused by Gram -ve bacteria?
Ans-Gram -ve bacteria cause various diseases in humans such as indigestion , food poisoning,meningitis,pneumonia and many other diseases.


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