"By approximately 4.5 to 5 menstrual weeks, the primitive neural plate has developed. The neural plate then divides into the neural crest and the neural tube. The neural tube differentiates into the primitive brain and the spinal cord 1-4."
"By approximately 4.5 to 5 menstrual weeks, the primitive neural plate has developed. The neural plate then divides into the neural crest and the neural tube. The neural tube differentiates into the primitive brain and the spinal cord 1-4."