2. Nucleoid or prokaryotic genetic material
Prokaryotic and eukaryotic are differs from each
other due to their genetic material.
As eukaryotic cells have two or more chromosomes
in nucleus with membrane bounded organelles.
In contrast prokaryotes lack a membrane-delimited
nucleus and organelles.
When the prokaryotic chromosome are located in
irregular shaped region then we call that nucleoid
(nuclear body, chromatin body, nuclear region).
3.
4. Usually prokaryotes contain a single circle of ds
DNA but some have a linear DNA chromosome such
as Vibrio cholera and Borrelia burgdorferi (the
causative agents of cholera and Lyme disease,
respectively), have more than one chromosome
Both electron and light microscopic are used for
understanding nucleoid structure and function,
especially during active cell growth and division.
5.
6. The nucleoid has a fibrous appearance in electron
microscope the fibers are probably DNA.
During cells division the nucleoid has projections
contain DNA that transcribed to produce mRNA that
extend into the cytoplasmic these projections.
more than one nucleoid can be observed within a
single cell when genetic material has been duplicated
but cell division has not yet occurred
7.
8. Nucleoids can be isolated.
Nucleoids are composed of about 60% DNA, 30%
RNA, and 10% protein by weight.
In E. coli, the closed DNA circle measures
approximately 1,400 m or about 230–700 times
longer than the cell
Unlike the eucaryotes and
some archaea, Bacteria do not use histone proteins
to package their DNA.