Meristematic tissue system
This includes 1) meristematic tissue characters
Meristematic tissue are the tissue which divide and
re-divide and helps in growth of parts of plant.
Characteristic
features of meristematic tissue-
1)
The cells are continuously divide.
2)They
have only primary cell wall so it is ease In division.
3)They
have dense cytoplasm to provide nourishment to cells.
4)
Normally they lack vacuoles(characteristic of plant cell) ,, but when cell
elongation takes place and vacuoles appears.
5)They
have prominent nucleus
6)Cytoskeleton
is absent, cytoskeleton required to provide framework to cell but cells are
continuously goes through division it is absent.
Where are they
present ?
a)In
root tip , we have seen meristematic region ,this is the region where
meristematic tissue is present at the lower region, and it forms root cap by
dividing the cells . In meristematic region in central some cells are present
which are twmprarily inactive and known as quiscent zone and this are non- dividing
cells but divides when necessary , they are of reserved type. Rot cap also
known as calyptra and therefore that meristematic tissue also known as
calyotrogen (calyptrogenerative cells).
b)In
shoot region , in shoot region or apical region of stem the meristematic
tissues are present but this cell give one meristematic cell and one permanent
cell and thus some cells are left between permanent cells and known as
intercalary cells(distinguishing feature of monocot, leaf elongation due to
this cells), also in lateral region in stem lateral meristem is present.
As on the basis of formation apical
meristem and intercalary meristem is known as primary meristem and lateral
meristem is known as secondary meristem.
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