BIOL303 Lecture Notes - Lecture 13: Sonic Hedgehog, Neural Crest, Neural Tube
Document Summary
Ectoderm: becomes the vertebrate nervous system and epidermis, epidermis is speci ed by high levels of bmp. Neural ectoderm: dorsal ectoderm cells that are columnar and become neural ectoderm. Neural plate: region of dorsal ectoderm speci ed to become neural ectoderm, speci ed by low levels of bmp, folds into the neural tube through neurulation. Neural tube: precursor to the cns (brain and spinal chord) Neural crest cells: progenitors off many different cell types of pns, speci ed by intermediate levels of bmp"s. Neurulation: the process where the neural plate folds to form the neural tube, aka. Notochord: transient mesodermal structure that forms the supporting axis of the embryo, forms as the primitive streak regresses. Neuroblast: neural precursor cell, speci cation = signal to become a neuroblast (reversible), determination = neuronal fate is determined, differentiation = neuroblasts stop dividing and express genes associated with neuronal function.