  Using the semiclassical Boltzmann transport theory, we analytically consider
dc charge transport in gapless electron-hole (both chiral and non-chiral)
systems in the presence of resistive scattering due to static disorder arising
from random quenched impurities in the background. We obtain the dependence of
the Boltzmann conductivity on carrier density and temperature for arbitrary
band dispersion in arbitrary dimensionality assuming long-range ($\sim 1/r$)
Coulomb disorder and zero-range white noise disorder [$\sim \delta(r)$]. We
establish that the temperature and the density dependence of the Boltzmann
conductivity manifests scaling behaviors determining respectively the intrinsic
semimetallic or the extrinsic metallic property of the gapless system. Our
results apply equally well to both chiral and non-chiral gapless systems, and
provide a qualitative understanding of the dependence of the Boltzmann
conductivity on the band dispersion in arbitrary dimensionality.
