Experimental data and modelling results. (Colour) A: Experimental measurements of ROS in guard cells (markers with error bars) and solutions of equation (1) (lines) as percentage of control. B: Stomatal aperture measurements (markers with error bars) and solutions of equation (6) (lines) as percentage of control. On each image we show the response to 10 μ M ABA (blue circles), 10 μ M ACC (red squares), and 10 μ M ABA + 10 μ M ACC (green diamonds). Error bars show the standard error of the mean (n=30×3). The solutions to the equations were obtained using the parameter values from Table S1 in the Additional file 1.