Simulation of two RS latches with varying degrees of crosstalk. A: Expected output of two ideal RS latches (substrate P is light grey, C is dark grey), B: biochemical latches with no crosstalk, C: minimal crosstalk, and D: moderate crosstalk. Stochastic results (solid lines) are superimposed with deterministic results (dashed lines) for panels B-D with substrates P (light lines) and C (dark lines). The relative values have been normalized to range between 0 and 1 as in a digital RS latch. For all panels the inputs were as follows: At t = 0 ms, S = 1, B = 1; at 1000 ms, R = 1, A = 1; at 2000 ms, R = 1, B = 1; at 3000 ms, A = B = S = R = 0; at 4000 ms, S = 1, A = B = 0; at 5000 ms, R = 1, A = 1; at 6000 ms, S = 1, A = 1; at 7000 ms, S = 1, B = 1.