What is another word for primitive sheath?
Pronunciation: [pɹˈɪmɪtˌɪv ʃˈiːθ] (IPA) 
The term Primitive Sheath is generally used to refer to the embryonic structure that gives rise to the nervous system. However, there are a variety of synonyms available that can be used in place of this term. Some of the commonly used synonyms include Neural Crest, Neural Tube, Neural Groove, and Neuroepithelium. These synonyms can be used interchangeably depending on the specific context in which they are being used. Regardless of the terminology used, it is important to note that the primitive sheath is a critical structure in embryonic development and plays a vital role in the formation of the brain and nervous system.
