What is the Cell Wall?

All plant cells are surrounded by a Cell Wall made mainly of Cellulose. Paper, which is made from Cell Walls, is also made of Cellulose. Cellulose belongs to a group of substances called Polysaccharides. Cellulose forms fibres that criss-cross over one another to form a very strong covering to the cell. This helps to protect and support the cell. Because of the spaces between the fibres, even very large molecules are able to go through the Cellulose Cell Wall. It is therefore said to be Fully-Permeable. Animal cells never have Cell Walls.