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 Parenchyma Collenchyma Collenchyma Sclerenchyma Sclerenchyma Examples of complex permanent tissues: Xylem (commonly called wood)‏ Xylem (commonly called wood)‏ Phloem (commonly called bast)‏ Phloem (commonly called bast)‏ Epidermis Epidermis Permanent Tissues

Characteristic: cells remain alive at maturity cells remain alive at maturity thin-walled cells thin-walled cells isodiametric shape isodiametric shape intercellular spaces intercellular spaces widespread occurrence in the plant body (leaves, root, stem)‏ widespread occurrence in the plant body (leaves, root, stem)‏ Parenchyma tissue

Parenchyma tissue under a microscop 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. 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 cells remain alive at maturity cell walls are thickened cell walls are thickened intercellular spaces absent or very small intercellular spaces absent or very small occurence in the peripheral regions of stems and leaves 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

Characteristic: Mature sclerenchyma cells are dead Mature sclerenchyma cells are dead Cells have thick secondary walls Cells have thick secondary walls Occurence in shells and the outer hard coat of many seeds Occurence in shells and the outer hard coat of many seeds Sclerenchyma Tissue

The shell of walnut as an example of sclerenchyma tissues 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: ◦ ◦ ◦ ◦ ◦ Literature: ◦ Kincl:Botanika

Created by Denisa Romanovska