Cell-wall is the non-living, outermost boundary of plant cells, bacterial cells, and fungal cells. It is not found in the animal cell. It is secreted by the protoplasm of the plant cell. In the plant cell, it is mainly composed of cellulose and pectin. Cellulose makes the fibers which are arranged in crises cross manner. These fibers are kept in their position by a cementing material called calcium pectate.
The thickness of cell-wall varies in different cells of a plant. It Is composed of three main layers: middle lamella, primary wall, secondary wall.
Cell wall provides protection and support to the cell. It gives a definite shape to the cell. It also performs the function of transport of material from outside to inside.