ABSTRACT
The cell wall is unique to plants and envelops the protoplast. Its presence or absence serves as a criterion to find out whether a given taxon is a plant or an animal. This characteristic is more reliable than the presence or absence of chlorophyll, as plant cells can change into a heterotrophic way of life by losing chlorophyll. By virtue of its strategic position and structural organization, the cell wall or the extracellular matrix is meant to give shape or rigidity as well as protection and support to cells and tissues. It is also involved in the dimensional changes of the cells as these changes inevitably lead to changes in wall structure. The interaction between cell shape, cell growth rate, wall structure, and wall mechanics is influenced in large part by changes in biochemical processes inside the cell and vice versa.
