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Updated: Jul 19, 2026
08:23
Finite Element Modelling of a Cellular Electric Microenvironment
Published on: May 18, 2021
Theory of electric dissipative structure in Characean internode
1Department of Electronics, Faculty of Engineering, Kyushu University 36, Fukuoka 812 Japan.
Biophysical Chemistry
|August 1, 1987
Summary
This study theoretically models the acidic and alkaline bands on Characean cell walls, revealing they are dissipative structures stabilized by ion transport. Changes in cell size and external viscosity influence pattern clarity and formation kinetics.
Area of Science:
- Cell Biology
- Biophysics
Background:
- Characean cells exhibit alternating acidic and alkaline bands along their cell walls.
- These patterns are crucial for understanding cellular transport and homeostasis.
Purpose of the Study:
- To theoretically investigate the formation and stabilization of band-type patterns of acidic and alkaline regions on Characean cell walls.
- To elucidate the role of ion transport and physical parameters in pattern development.
Main Methods:
- Development of a theoretical model using linear diffusion equations for H+ concentration.
- Incorporation of plasmalemma transport under light energy supply.
- Numerical calculations and analysis using a time-dependent Ginzburg-Landau equation.
Main Results:
- The band pattern is identified as a dissipative structure stabilized by electric current loops from electrogenic H+ pumps and passive ion fluxes.
- Larger vacuoles and smaller extracellular water phases promote clearer band patterns.
- Increased external medium viscosity enhances band appearance and distinctness.
- Extracellular water phase size significantly impacts pattern formation kinetics.
Conclusions:
- The theoretical model successfully reproduces experimental observations of band pattern formation.
- Electric current circulation between acidic and alkaline regions is key to pattern stabilization.
- Physical parameters like vacuole size, extracellular water volume, and medium viscosity critically influence the observed patterns.
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