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
GENERALIZED PROKARYOTIC CELL
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