STRUCTURAL MECHANICS OF PLANT-CELLS

The precise quantification of the structural behaviour of living plant cells presents many difficulties. In view of this, an approximate model has been developed by treating the cells as flexible shells having simple geometrical shapes, and subjected to internal pressure. The analysis assumes the cell walls to be made of long-chain polymeric substances whose stress-deformation behaviour can be characterised either by a Mooney-Rivlin or neo-Hookean material. The presence of microfibrils in plant cell walls has been simulated by treating the shells as being reinforced by thin inextensible, but flexible, cords. The established theories of large elastic deformations of such reinforced materials are used in the main analysis. The two main problems dealt with are the relationship of cell volume to turgor pressure and the time course of cell enlargement with influx of water. The analysis also allows for known external stress conditions on the outer periphery of the cells. The complicated closed equations derived are presented in the form of charts using non-dimensional parameters. These charts form the basis for the calculation of absolute values for a wide range of practical conditions obtaining in nature. The performance of the models is considered in relation to recent experimental data. © 1978.