<prompt> Which process establishes the three definitive germ layers?NeurulationGastrulationCraniocaudal foldingLateral folding  <response>: Gastrulation - three primary germ layers from epiblast during week 3 of development i.e dorsal ectoderm, middle mesoderm, ventral endoderm. Neurulation is the process by which neuroectoderm forms the neural plate, which eventually folds to form the neural tube. 