Assuming 100 µm of contact area between cells, the steady state flux would be 5 × 10 -20 moles of sorgoleone per second, or about 30,000 molecules per second. Naturally, as the initial intracellular concentration goes down, this steady state flux would as well. Crucially, we are assuming that the concentration differences across the plant are governed primarily by membrane traversals, rather than other potential transport mechanisms through the xylem or phloem or junctions between plant cells.