In 1857 in Paris, the second chemical method was developed using sulfates. Still today, one of these two methods for separating wood fibers is used. Indeed, it is the same thing your doctor tells you you need to eat more of, it is present in bran muffins and in fruits and vegetables, in corn husks and tree leaves. Fiber is everywhere. Basically, fiber is cellulose .
Plants make cellulose as a part of their cell walls and it is used for structural support.
In animal cells, the border of a cell is defined by the plasma membrane. Plant cells, too, have plasma cell membranes defining their edges. This is known as the cell wall . The cell wall varies according to the tissue and the amount of support needed by it. Primary cell walls have a high tensile strength and are porous.