Cell wall
Cell wall is the unique structure in plant cells of which absent in any eukaryotes animal cell. Plasma membrane is surrounded by cell wall can increase the plant cell with tensile strength, osmotic stress and mechanically protection. Furthur more, plant cells can develop turgor pressure with the present of cell wall of which is the pressure of the cell contents against the cell wall.
Plant cell wall consist of three major layers : plasma membrane, primary cell wall and a middle lamella. Middle lamella is the outermost layer of the cell wall contecting the environment of which containing soluble protein and pectin. Primary cell wall contain cellulose microfibrils, hemicellulose, pectin, lignin, and soluble proteins.
Cell wall helps to maintain plant cell structure integrity in different conditions. In normal supply of water, water molecules diffuse into the plant cell via osmosis where the cytoplasm of the plant cell is lower than water since the present if high concentration of soluble molecules. Cell wall prevent plant cell from burst against the over intake of water. In drought, plant cell lose water though transpiration that cells will be wilt and cell walls keep the plant structure of integrity.