Physical Concepts of Plant Water Relation - Diffusion
Diffusion is a spontaneous process that leads to net movement of a substance from a region of higher concentration to a region of lower concentration. it can also be defined as the net movement of molecules from region of high free energy to a region of low free energy. The principle of diffusion is of importance in plants because several of the transport processes such as uptake of water and minerals, intake of CO2 and release of O2 by leaf cells, loss of water due to transpiration depend in part on diffusion.