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Tissues are groups of cells with similar structure, origin and function.
Plant tissues can be divided into two types: meristematic
(perpetually young tissues important in growth) permanent
Simple tissue is composed of one kind of cell.
Complex tissue is composed of two or more kinds of cells.
Meristematic Tissues
are groups of cells that have the ability to divide.
Characteristic:
the cells are small
the cell walls are thin
cells have large nuclei
vacuoles are absent or very small
no intercellular spaces
Locations:
tips of roots, stems, buds
are derived from meristematic tissues.
They have lost the power of dividing.
Simple permanent tissues:
Parenchyma
Collenchyma
Sclerenchyma
Examples of complex permanent tissues:
Xylem (commonly called wood)
Phloem (commonly called bast)
Epidermis
Permanent Tissues
Characteristic:
cells remain alive at maturity
thin-walled cells
isodiametric shape
intercellular spaces
widespread occurrence in the plant body
(leaves, root, stem)
Parenchyma tissue
In the different regions of the plant body parenchyma cells are involved in different functions.
For example: Aerenchyma
The cells enclose large
intercellular spaces that are
filled with air. Aerenchyma
helps to transport oxygen
produced during photosynthesis.
It is characteristically found in aquatic floating plants.
Types of Parenchyma
Characteristic:
cells remain alive at maturity
cell walls are thickened
intercellular spaces absent or very small
occurence in the peripheral regions of stems and leaves
Collenchyma Tissue
Collenchyma TissueStalk of begonia under a microscop
par – parenchyma
kol – collenchyma
e – epidermis (covers the plant)
bs – cell walls
Characteristic:
Mature sclerenchyma cells are dead
Cells have thick secondary walls
Occurence in shells and the outer hard coat of many seeds
Sclerenchyma Tissue
Questions for you
Which are the growth tissues of plants?
The growth tissues of the plants are the meristems.
Which are the plant tissues responsible for supporting of the plant??
The plant supporting tissues are the collenchyma and the sclerenchyma.
Which is the plant tissue responsible for filling of the space between other tissues?
The plant-filling tissue is generically called parenchyma.
Which tissue does the husk of a coconut contain??
SclerenchymaSclerenchymatous cells are dead cells. The
fibrous husk of coconut is also dead.
Resources
Internet:◦ http://botanika.wendys.cz/slovnik/foto.php?80_1◦ http://botanika.wendys.cz/slovnik/foto.php?81_1◦ http://www.odmaturuj.cz/biologie/rostlinna-pletiva/◦ http://botanika.borec.cz/o_pletiva.php#deliva◦ http://www.biologie.webz.cz/www/botanika/anatomie.html
Literature:
◦Kincl:Botanika