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The structure of the nucleon and the first radial excitation of the nucleon,the Roper, $N(1440)$, is studied within the formalism of Light-Frontholography. The nucleon elastic form factors and $\gamma^\ast N \to N(1440)$transition form factors are calculated under the assumption of the dominance ofthe valence quark degrees of freedom. Contrary to the previous studies, thebare parameters of the model associated with the valence quark are fixed by theempirical data for large momentum transfer ($Q^2$) assuming that thecorrections to the three-quark picture (meson cloud contributions) aresuppressed. The $\gamma^\ast N \to N(1440)$ transition form factors are thencalculated without any adjustable parameters. Our estimates are compared withresults from models based on valence quarks and others. The model compares wellwith the $\gamma^\ast N \to N(1440)$ transition form factor data, suggestingthat meson cloud effects are not large, except in the region $Q^2< 1.5$GeV$^2$. In particular, the meson cloud contributions for the Pauli form factorare small.

Valence quark contributions for the $\gamma^\ast N \to N(1440)$ form factors from Light-Front holography