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Showing posts with the label #Reproduction in Organisms

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...

Reproduction in Organisms for Class 12 Chapter 1 Biology Notes

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            Life Span ** The period from birth to the natural death of an organism is called life span. **Life span vary from few days to thousand years. **Life span of an organism does not related with their sizes. Example :Size of crow and parrot are nearly same but their life span show wide differences. **No organism is immortal, except single celled organisms. **Life span of some organisms:   Elephant     : 65years   Dog             : 20-30 years   Cow.           : 20-25 years   Horse         : 25-39 years   Crow           : 15 years   Parrot.        : 140 years   Fruitfly        : 1 month   Butterfly.    : 1-2 weeks   Tortoise     : 100-150 years   Crocodile    : 60 years   Rose.  ...