[Fe/H] for bulge (squares) and disk (circles) components as function of galaxy stellar mass. The solid lines denote the median trends for both components (orange and yellow, respectively). Left-hand panel: Plane is color-coded by bulge-total-ratio. Right-hand panel: Median age of the corresponding components. The disk components with an excess of [Fe/H], with respect to the disk MZ_*R, are highlighted. To quantify third dependences of the bulge, partial correlation coefficients analysis (PCC, Bluck et al. 2020) angles are included.