  We have studied nuclear structure functions $F_{1A}(x,Q^2)$ and
$F_{2A}(x,Q^2)$ for electromagnetic and weak processes in the region of $1
GeV^2 < Q^2 <8 GeV^2$. The nuclear medium effects arising due to Fermi motion,
binding energy, nucleon correlations, mesonic contributions and shadowing
effects are taken into account using a many body field theoretical approach.
The calculations are performed in a local density approximation using a
relativistic nucleon spectral function. The results are compared with the
available experimental data. Implications of nuclear medium effects on the
validity of Callan-Gross relation are also discussed.
