  We study the dynamics of the scalar modes of linear perturbations around a
flat, homogeneous and isotropic background in loop quantum cosmology. The
equations of motion include quantum geometry effects and hold at all curvature
scales so long as the wavelengths of the inhomogeneous modes of interest remain
larger than the Planck length. These equations are obtained by including
holonomy corrections in an effective Hamiltonian and then using the standard
variational principle. We show that the effective scalar and diffeomorphism
constraints are preserved by the dynamics. We also make some comments regarding
potential inverse triad corrections.
