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PROKARYOTIC ORGANISMS

 PROKARYOTES

DEFINITION ;

PROKARYOTIC CELLS HAVE NO PROMINENT NUCLEUS AND MEMBRANE

   BOUND ORGANELLES . 

DERIVED FROM;

IT IS DERIVED FROM GREEK WORD PRO MEANS "BEFORE" AND KARYON

   MEANS "NUCLEUS".

GENETIC MATERIAL;

IN PROKARYOTIC CELLS THE GENETIC MATERIAL (DNA) IS WITHOUT ANY

   NUCLEAR MEMBRANE COVERING AND IS DIRECTLY SUBMERGED IN THE

  CYTOPLASM.

PROKARYOTES;

ORGANISMS POSSESSING PROKARYOTIC CELLS CALLED PROKARYOTES.

DIVISION OF CELLS;

IN PROKARYOTES MITOSES IS MISSING AND CELL DIVIDES BY BINARY 

   FISSION.

RIBOSOMES;

PROKARYOTIC CELLS HAVE SMALL SIZED RIBOSOMES "SEDIMENTS AT 

 70S".

DISTINCTIVE FEATURE OF PROKARYOTES;

PERHAPS THE MOST DISTINCTIVE FEATURE OF THE PROKARYOTIC CELL IS

   ITS "CELL WALL" ,COMPOSED OF POLYSACCHARIDE CHAINS BOUND BY

   COVALENTLY TO SHORTER CHAINS OF AMINO ACIDS FORMING

 PEPTIDOGLYCON OR MUREIN.

FOR EXAMPLES;

BACTERIA

CYANOBACTERIA (BLUE GREEN ALGAE)

E.COLI (ESCHERICHIA COLI)

MYCOPLASMA

ARCHAEA

prokaryotic cells

 GENERALIZED PROKARYOTIC CELL

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