USMLE-Rx 's Next list Neurology and Special Senses Development of the Nervous System Last Updated: May 26, 2021 access_time 14 min Learning Objectives After completing this section, you will be able to: <span>List the derivatives of ectoderm.1 Define neurulation and explain how it occurs, including closure and the dates of neuropore closure.2 Describe the origin, migration, and fate of neural crest cells, partic