We show that the multiphase chemical evolution model reproduces the
correlations obtained along the spiral sequence, dwarf galaxies included.
However the apparent spatial chemical uniformity observed in some irregular
galaxies cannot be reproduced with it. An evolutionary model has been developed
and tested to explain flat gradients. Preliminary results, obtained with a new
code including supernova winds and radial flows, suggest that radial flows are
probably responsably for this uniformityComment: 5 pages,5 figures, to be published in the proceedings of the ESO
"Chemical Evolution from Zero to High Redshift" workshop, Eds. M.Rosa and
J.R. Walsh (Springer-Verlag
