Hα/continuum distribution for galaxies in our sample with spectra in zCOSMOS. Different lines show: the distribution of the 51 Sknot+diffuse and Mknots galaxies (solid line) with a fitted Gaussian profile overplot; the distribution of a subsample of nine galaxies with bright knots (dot-dashed line), its luminosity being twice or more that of the host galaxy, and the distribution of the 25 Sknot galaxies (dashed line) with the fit of a Gaussian overplot.