  Electron scattering problem in the monolayer graphene with short-range
impurities is considered. The main novel element in the suggested model is the
band asymmetry of the defect potential in the 2+1-dimensional Dirac equation.
This asymmetry appears naturally if the defect violates the symmetry between
sublattices. Our goal in the present paper is to take into account a local band
asymmetry violation arising due to the defect presence. We analyze the effect
of the electron scattering on the electronic transport parameters in the
monolayer graphene. The explicit exact formula obtained for S-matrix for the
suggested delta-shell potential model allowed us to study the asymptotic
behavior of such characteristics as scattering phases, transport cross section,
the transport relaxation time and the conductivity for small values of the
Fermi energy. The obtained results are in a good agreement with the
experimental data which shows that the considered model is reasonable.
