Plate 28
|
PLATE NUMBER |
STAGE |
TIME |
ORIENTATION |
IMAGE |
|
28 |
Neural tube stage Embryo stage 20 |
21 h 45 min p.f. |
Dorsal Posterior Ventral |
Sagittal section |
Anterior
Neural tube stage (embryo stage 20)
In this stage, the cells are re-arranged within the Notochord. The cells differentiatefaster in the anterior as compared to the posterior region of the mesoderm. At this stage, the brain start to be subdivided into archencephalic and deuterencephalic regions. The closure of the neural tube has led to the formation of a central canal. The anlage of the cement gland start to protrude A prominent feature of the anterior archenteron is an oral evagination.