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

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

Parenchyma tissue under a microscop

i - intercellular space

bs – cell walls

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

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??

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

Created by

Denisa Romanovska