Principles of Biochemistry

1.1.3.7 Cell Wall

The cell wall gives a definite shape and provides proection to the protoplasm. It is non-living in nature and and is permeable. Adjacent cells in the plant body remain inter connectd by plasmaodesmata. The cell wall of plants is made of fibrils of cellulose embedded in a matrix of several other kinds of polymers such as pectin and lignin which provide mechanical strength to the cell. Cell wall consists of 3 parts:

i) Middle lamella-made of pectic acid in the form of Ca and Mg salts.

ii) Primary wall-made of cellulose

iii) Secondary wall-pronounced in dead cells, viz  tracheids and sclerenchyma.