Cell:-The unit of
life
All living
things are made up of cells .so , cell
is called the unit of life. Even a single cell has capacity to generate its
life independently…
Ex:-prosita and monera are single cell organization.while
fugi ,plantae and animalia are made up of trillions of cell
Its amaze ‘s to
know you that human brain alone contain billion’s of cells
Cell Theory
1.-All living things are made up of cells and product of
cells
2.Cell are the units of structure and function of life and
all the cells are identical at chemical level
Above
mentioned cell theory was given by Schleiden
(1838) and Swan (1839)
3”omnis cellula e cellula “(All cells arises from
preexisting cells) was given by Rudorf Virchow (1858)
Types of cells (on the basis of organization )
1.prokaryotes :
Shape1to 2 micro meter
Lack membrane bounded structure
Ex: mycoplasma bacterial cell
2.Eukaryotic cell :
Shape10 to 30 micro meter
Presence of membrane
bounded structure
Ex; Mitochondria ,
golgi body ,lysosomes e.t.c
MESOKARYON:- “Mesokaryon” term
proposed by Dodge
To describe
nucleus of cells of Dinoflagellates
In
interphage stage “ Mesokryon nucleus has condensed chromosomes which lack
histon protein (basic in nature)
Types of cells ( on the basis of
labour)
1Undifferentiated cell:-cells
capabal of division and development
Ex: stem cells of
animal cells , zygote cell
2differenciated cell:-post mitotic
cell ,which became specialized due to
division of labour
3Dedifferentiated cell:-
Differentiated cell revert to become undifferentiated cells
Ex:-vegetative propagation in plant cell.
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