Simple tissue

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Plant Tissues
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
Permanent Tissues
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
Parenchyma tissue
Characteristic:
 cells remain alive at maturity
 thin-walled cells
 isodiametric shape
 intercellular spaces
 widespread occurrence
in the plant body
(leaves, root, stem)
Parenchyma tissue under a microscop
i - intercellular space
bs – cell walls
Types of Parenchyma
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.
Collenchyma Tissue
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
Stalk of begonia under a microscop
par – parenchyma
kol – collenchyma
e – epidermis (covers the plant)
bs – cell walls
Sclerenchyma Tissue
Characteristic:



Mature sclerenchyma cells are dead
Cells have thick secondary walls
Occurence in shells and the outer hard coat of many seeds
The shell of walnut as an example of sclerenchyma tissues
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??
Sclerenchyma
Sclerenchymatous 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
Created by
Denisa Romanovska
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