Similarity between longitudinal C1 and transverse E1 (e,e') form factors taking place at low momentum transfers q disappears with growing q as a result of different q-dependences of form factors (f.f.) responsible for forward and backward.electron scattering. The breaking of form factors similarity is caused by interplay between the orbital and spin nucleon currents in transverse f.f.[1]. For example, in¹²C(e,e'p₀) reaction this interplay leads to a decrease in the transverse f.f. compared to the longitudinal one at q=0.4-0.6 fm^-1.(Fig.1). This effect was observed at MAMI-A [2]. In case of ¹²C the main peak of dipole resonance is mainly formed by 1p_3/2 ? 1d_5/2 transition and its transverse f.f. has a minimum at q=0.5 fm^-1 due to the interference of intranucleus currents. For ¹⁴C(e,e'n_o) reaction the transverse f.f. is determined by an important role of 1p_3/22s transition which has no minima at q<1 fm^-1. Therefore, the role of destructive interference between the orbital and spin nuclear currents is not so drastic as in¹²C(e,e'p₀).

Similar effects were revealed in electrodisintegration of 1d-2s nuclei. The comparison of (e,e'p₀) reaction in ²⁸Si,³²S and ⁴⁰Ca has shown that the much drastic contrast between forward (mostly C1) and backward (E1) partial cross sections at 0.5 Fm^-1 should be in ²⁸Si since the 1d _5/21f _7/2 transition dominates in its dipole resonance.