EVERYDAY SCIENCE

Detailed explanation-1: -The cell wall is the outer covering of a cell, present adjacent to the cell membrane, which is also called the plasma membrane. As mentioned earlier, the cell wall is present in all plant cells, fungi, bacteria, algae, and some archaea.

Detailed explanation-2: -Cytoskeleton. The composition of cell walls varies between taxonomic group and species and may depend on cell type and developmental stage. The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses and pectin.

Detailed explanation-3: -The cellulose molecules provide tensile strength to the primary cell wall. Each molecule consists of a linear chain of at least 500 glucose residues that are covalently linked to one another to form a ribbonlike structure, which is stabilized by hydrogen bonds within the chain (Figure 19-70).

Detailed explanation-4: -Cytoskeleton. The cytoskeleton is a network of long fibers that make up the cell’s structural framework. The cytoskeleton has several critical functions, including determining cell shape, participating in cell division, and allowing cells to move.

Detailed explanation-5: -What Is the Cell Wall? A plant cell wall is arranged in layers and contains cellulose microfibrils, hemicellulose, pectin, lignin, and soluble protein. These components are organized into three major layers: the primary cell wall, the middle lamella, and the secondary cell wall (not pictured).