Systems response to sinusoidal ethylene input. (a) Amount of ERF1 accumulated in the root cell nucleus for different values of ω of a periodic variation of ethylene according to the function ET = 0.5 + 0.5sin (ωt). The values of ω are shown in the small square inside the figure. (b) Amount of information managed by the ethylene root cell as a function of the probability of expression of the ERF 1 gene and the amount of ERF1 protein in the nucleus. A denotes a ω value of 0.005 s-1; B, a value of 0.0005 s-1.