Fractional radius of the inner zone of the uniform oxygen abundance as a function of rotation velocity (panel a), stellar mass (panel b), optical radius (panel c), median value of star ages estimated from the D_n(4000) index (panel d), and the median value of luminosity-weighed stellar ages from Sánchez et al. (2022, panel e). The circles denote galaxies with an L-type abundance distribution, the plus signs mark galaxies with an LS-type abundance distribution, and crosses are galaxies with an S-type abundance distribution.