Do electrons scatter off of the up quarks inside protons and neutrons? Since they are different types of fermions, and of opposite charge, and the up quark has only 2/3 of a 'full' charge; is its trajectory changed as much by scattering off of a same-charge down quark?
Since the down quark has only 1/3 as much charge, does it scatter an electron by only half as much as when it nears an up quark?
 A: *

*Quarks scatter among themself via strong interaction, so the role of quark's electric charge is neglegible.


*It depends on the amount of energy transfer of the electron to its scattering partner. If the energy transfer is small, the electron only sees the scattering partner as protron, in particular its charge distribution (electric form factor) and its magnetic formfactor. The scattering is elastic and can be described by the "Rosenbluth" formula. If, however, the energy transfer is large -- i.e. the deBroglie wave length is substantially smaller than the extension of the proton's charge distribution -- the exchange particle  which apart from a photon also includes $W^{+-}$ and $Z^0$, hits a quark (up or down) or even sea-quarks (glimpses of intermediate states of gluons). This process is called "deep inelastic scattering" (DIS). The hit quark  might change its flavour according to the corresponding exchange particle and be hit out of proton. On a later stage it undergoes hadronisation as well as the 2 remaining (not hit) quarks. Only electrons  with enough high energy can make a DIS.
The cross section mostly depends on the quark distribution (parton structure function). Actually we cannot say if the shock of the hit quark depends on its charge, because due to QM we do not know which particle is exchanged ($\gamma$, $Z^0$) There is even a third exchange particle
($W^{+-}$) possible, but distinguishable from the 2 other ones through the final state ( see below). Only the photon couples solely to charge where the other exchange particles couple to weak interaction quantum numbers like weak isospin or weak hyper charge.
BTW the electron scatters off if a photon or a $Z^0$ is exchanged. Otherwise it turns into a neutrino ($W^{+-}$ exchange). In low-energy elastic scattering it scatters off as an electron.
Whole HighEnergy experiments ZEUS/H1 were devoted to study this process in detail.


*Quark intra scattering and quark-electron scattering are so different so that they cannot easily compared because in quark scattering always the parton structure functions come in which complicates enormously the comparison.
