- Cell wall was first observed by Robert Hooke in 1665.
- Cell may consist of three layers :- Primar wall , Secondary wall and Middle lamella.Sometimes tertiary wall also develop.
- Cell wall made up of three things :-
- Matrix :- non cellulosic. gelly like ground substance in cell wall in which all other materials are embedded. No cellulose but hemicellulose is in abundance.Act as a binder.
- Fibrils :- These are macrofibrils. Made of cellulose.Provide rigidity to cell wall. each macrofibril is s60 angsrom think and made of 20 micelles.
MICELLES ARE ELEMENTARY UNIT OF CELL WALL.
- Depositions : - Like of silica, cutin , lignin. wax and suberin. [ very important things but extensive , if u need to know about them then just inform me].
4. Middle lamella :- thin cemeting layer which join two cells together. pectin is main material in
it. It is formed by Golgi body and endoplasmic reticulum.
5. Primary wall :- Found in all cells.Elastic in nature. Main material is auxin. Lignin is totally absent in it.
6. Secondary wall:- think and inelastic. It forms in those cells which stopped dividing. It is mainly composed of three layes S1, S2 and S3.
to be continued ...........
