The protoplast is the cell s way of making more wall. The shape of a plant cell is dictated largely by its cell wall. In living cells, the cell wall constrains the rate and direction of cell growth, exerting a profound influence on plant development and morphology.
Cell walls contribute to the functional specialization of cell types.
The spongy parenchyma of a Zinnia leaf minimizes cell contact and maximizes cell surface for gas exchange. The specialized shapes of these epidermal cells reflect light to enrich the colors of a snapdragon petal. The secondary thickenings of a tracheid prevent collapse of the wall from the tension created by the transpirational pull. An Arabidopsis trichome is an exquisitely branched modified epidermal cell. The plant cell wall is a dynamic compartment that changes throughout the life of the cell.