The effect of nuclear forces, or the effect of the quasi-deuteron model, is discussed for the integrated cross section and the bremsstrahlung weighted cross section. The nuclear force is assumed to be of partly Majorana exchange character. Only the central force is considered. The two-body potential is a Gaussian type without a hard core, the parameters of which are taken from the effective range theory. The calculations are performed by first-order perturbation theory and the results are that the integrated cross section is increased by about ten percent and the bremsstrahlung weighted cross section is decreased by a few percent. Therefore the independent-particle model can be regarded as a good approximation for photonuclear reactions.