The dynamical breaking of chiral symmetry in QCD is caused by nonperturbative interactions with a range rho ~ 0.3 fm, much smaller than the typical hadronic size. Recent theoretical work has studied the effects of these interactions on the nucleon’s partonic structure at a low scale: (a) Sea quarks have intrinsic transverse momenta up to the scale 1/rho, much larger than those of valence quarks. (b) Sea quarks exhibit short-range correlations of size rho with characteristic quantum numbers (sigma, pi), analogous to NN correlations in nuclei. The effects are demonstrated in a model of low-energy dynamics based on the large-N_c limit of QCD. They can be tested experimentally and have numerous implications for hadron production in semi-inclusive deep-inelastic scattering (HERMES, COMPASS, JLab 12 GeV), dilepton production in hadron-hadron scattering (FNAL, COMPASS, RHIC W, J-PARC), and multiparton processes in high-energy pp collisions (LHC).