Cell wall introduction

Cell wall introduction The cell wall is the outermost part of bacteria fungi and plant cell.
In Plant it is composed of cellulose and Hemicellulose, while the bacterial cell wall consist of protein lipid polysaccharide complex.
The cell wall is the most important feature of plant, it distinguished them from Animal because Animal are not have cell wall

Cell wall in Bacteria

The outermost boundary of the bacteria or envelope is called cell wall or ECM (Extracellular material)
It is rigid and present outside to the plasma membrane depending upon the constitution of cell wall and their staining reaction bacteria are two types.

In gram positive bacteria cell wall is composed of peptidoglycan, (Carbohydrate + Amino Acids) Ex. Bacillus Bacteria

In Gram negative bacteria a second outer lipopolysaccharide layer is located outside the thin peptidoglycan layer.ex. E.Coli.Bacteria

It is mainly composed of cellulose hemicellulose and pectic acid
Cell wall differ in its composition in different cell type
It is a characteristic feature of the plant cell.
It is completely absent in animal cells
It is the outermost, non-living thick rigid and porous layer that covers the plasma membrane of the cell.
It is secreted by protoplast as a cellulosic fiber on plasma membrane
In young plant cell it is very thin elastic and delicate layer about 1 to 3 µ thick but after the modification by various way it become stiff 5 to 10µ thick as the cell matures.

The cell wall of parenchyma tissue cell are comparatively thinner then collenchyma sclerenchyma and xylem and vessels cells.
In structure of cell wall two component fibrils and matrix are present which are chemically composed of polysaccharides.
The fibrils are made of cellulose and matrix part is made by hemicellulose and pectin substance.
During development and modification of cell wall other substance such as protein, lignin, lipids , suberin cutin, resin gum tannins wax etc. are also deposited on cell wall