File:Stage7 800x700px.jpg: Difference between revisions

Revision as of 15:50, 17 August 2014

Carnegie Stages 7

Features: embryonic disc, primitive node, primative streak, primative groove, yolk sac

Facts: Week 3, 15 - 17 days, 0.4 mm

View 1: embryonic disc, showing the epiblast viewed from the amniotic (dorsal) side.

Stage 7 Labelled | Stage 7 Molecular | Stage 7 SEM | Stage 8

Events: Gastrulation is continuing as cells migrate from the epiblast, continuing to form mesoderm.

Mesoderm lies between the ectoderm and endoderm as a continuous sheet except at the buccopharyngeal and cloacal membranes. These membranes have ectoderm and endoderm only and will lie at the rostral (head) and caudal (tail) of the gastrointestinal tract.

From the primitive node a tube extends under the ectoderm in the opposite direction to the primitive streak. This tube forms first the axial process then notochordal process, then finally the notochord.

The notochord is a key to embryonic folding and regulation of ectoderm and mesoderm differentiation. It lies in the rostrocordal axis and the embryonic disc will fold either side ventrally, pinching off a portion of the yolk sac to form the lining of the gastrointestinal tract.

Embryo Stage 7 (dorsal)
Dorsal view
Primitive streak and node
Oral and cloacal membranes
Axial mesoderm
Paraxial mesoderm
Intermediate mesoderm
Lateral plate

Image Source: UNSW Embryology http://embryology.med.unsw.edu.au/wwwhuman/Stages/stage7.htm

No image reuse without permission.

File history

Click on a date/time to view the file as it appeared at that time.

	Date/Time	Thumbnail	Dimensions	User	Comment
current	11:11, 10 August 2009		690 × 800 (69 KB)	MarkHill (talk \| contribs)	Carnegie Stages 7 Features: embryonic disc, primitive node, primative streak, primative groove, yolk sac Facts: Week 3, 15 - 17 days, 0.4 mm View 1: embryonic disc, showing the epiblast viewed from the amniotic (dorsal) side. Stage 7 Labelled \| Stage

You cannot overwrite this file.

File usage

The following 17 pages use this file:

@@ Line 16: / Line 16: @@
 The notochord is a key to embryonic folding and regulation of ectoderm and mesoderm differentiation. It lies in the rostrocordal axis and the embryonic disc will fold either side ventrally, pinching off a portion of the yolk sac to form the lining of the gastrointestinal tract.
+{{Stage 7 mesoderm images}}
 Image Source: UNSW Embryology http://embryology.med.unsw.edu.au/wwwhuman/Stages/stage7.htm