Impact of differential β3a vs. β2 inactivation likelihoods (L β3a , L β2 ) on relationship between slow tail amplitudes and f ss for the random mixing model. (A) Plot of the AST vs. fss relationships for the indicated β2:β3a ratios for the case of equal inactivation rates (kβ3a = kβ2). (B) AST vs. fss with kβ3a = 2kβ2. (C) AST vs. fss with kβ3a = 3kβ2. (D) AST vs. fss with kβ3a = 4kβ2. (E) Overlaid curves for kβ3a/kβ2 of either 1 or 4 (dotted lines). (F) Same as E on log axis. Overall, although changes in relative likelihood of β3a vs. β2 inactivation alter the relationship between normalized slow tail amplitude (AST) and steady-state current amplitude (Gss/Gmax) during trypsin digestion at different initial β2:β3a ratios, the overall impact is rather modest and does not alter the basic curvature in the AST vs Gss relationship predicted by the random mixing model.