Plate 20

Copyright © 1995
to the
"Frontiers in Bioscience"

Neural plate stage (embryo stage 14)

At this stage, blastocoel has virtually disappeared and the notochord is surrounded by the notochordal sheath. There are several cell layers in the sensorial layer of the neurectoderm. The appearance of the bottles cells is an indication that the the neural groove is being developed. Within mesoderm, various structures are well defined. Lateral mesoderm is developing two distinct cell layers and is separating from the endodermal yolk mass.