where the molecular flux (J) is proportional to the permeability coefficient, the contact surface area (A), and the change in concentration between the adjacent compartments (∆ C). If there were a thousand membrane traversals between a root hair with our high 1 nM intracellular concentration and a photosynthetic cell that initially has no sorgoleone in it and may have some slow degradation process to metabolize sorgoleone, the eventual solution is for a steady state to be reached. The concentration difference between individual cells would only be on the pM scale, as the overall ∆C between the start and end-points would be evenly divided across all the membranes separating compartments that need to be traversed.