A term used in embryology to describe the period between two weeks and eight weeks of gestation when the baby experiences rapid growth in organ and organ systems development. During this period the baby is extremely vulnerable to environmental hazards and toxic substances and any interference with the sequential processes may result in congenital abnormalities.
In animal development, organogenesis is the process by which the ectoderm, endoderm, and mesoderm develop into the internal organs of the organism. The germ layers in organogenesis differ by three processes: folds, splits, and condensation. Developing early during this stage in chordate animals are the neural tube and notochord.