Evolution up to the AGB tip of C, N, and O elemental and isotopic ratios in a 2 M_⊙ model with both RGB and AGB extra mixing. In the first case the maximum temperature was fixed to T_max = 22 MK, while in the latter T_max = 40 MK (see text for further details). The evolutionary timescale was rescaled to t_f = 1.196 Gyr, which corresponds to the age of the last computed model (AGB tip). The FDU occurs at log t/ (t−t_f) ~ 0.7, while some effect of the RGB extra mixing is visible a bit later. Finally the combined actions of the and the AGB extra mixing arise at log t/ (t−t_f) > 2.8.