Which process establishes the three definitive germ layers?
Neurulation
Gastrulation
Craniocaudal folding
Lateral folding
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.
Development period- week 1,2,3,4