Evaluating cell wall structure

Tobias Baskin

The form of plant organs such as leaves, roots, and flowers, reflects an equilibrium between an osmotic force drawing water in and a tension borne by the cell wall that resists this influx. This opposition holds plants erect against gravity and yet lets them bend rather than break in wind or rain. This equilibrium is broken by growth, which here means an irreversible volume increase. Growth occurs when the tension within the cell wall weakens, thus allowing water uptake. The osmotic force is isotropic; however, expansion is usually anisotropic, implicating the mechanical properties of the cell wall as governing the pattern of growth. Beyond this implication, relationships between cell wall structure and rates of expansion are largely conjectural.

Proceedings of the 6th Mathematics in the Plant Sciences Study Group