Carnegie stage 7: Difference between revisions

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==Kyoto Collection==
==Kyoto Collection==
{|
{|
| [[Image:Stage7 features.jpg|left]]  
| [[Image:Stage7 features.jpg]]
| [[File:Stage7.jpg]]
| '''View:''' embryonic disc, showing the epiblast viewed from the amniotic (dorsal) side. Head to tail orientation is Cranial (image top) and Caudal (image bottom).
| '''View:''' embryonic disc, showing the epiblast viewed from the amniotic (dorsal) side. Head to tail orientation is Cranial (image top) and Caudal (image bottom).



Revision as of 12:40, 17 March 2012

Introduction

Stage7-bf1.jpg

Facts

Human embryonic stage 7 occurs during week 3 between 15 to 17 days.

The embryo is now 0.4 mm diameter in size.

The initial images are displayed unlabeled to allow you to explore the embryo for yourself, linked labeled versions are also available for some images.

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.


Links: Week 3 | Gastrulation | Lecture | Practical | Stage 8
Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Bright Field Lateral

Stage7-bf1.jpg Stage7-bf2.jpg Stage7-bf3.jpg Stage7-bf4.jpg

Scanning EM

Stage7-sem1.jpg Stage7-sem4.jpg
Human embryonic disc
  • epiblast layer, dorsal view
  • primitive streak (left)
  • connecting stalk (far left)
  • amniotic sac removed
Human embryonic disc
  • epiblast layer, dorsolateral view
  • primitive streak (left)
  • connecting stalk (far left)
  • amniotic sac removed
Stage7-sem2.jpg Stage7-sem5.jpg

Primitive streak detail (left)

Human embryonic disc
  • epiblast layer, dorsal view
  • primitive streak (bottom)
  • connecting stalk (bottom)
  • amniotic sac removed

Kyoto Collection

Stage7 features.jpg Stage7.jpg View: embryonic disc, showing the epiblast viewed from the amniotic (dorsal) side. Head to tail orientation is Cranial (image top) and Caudal (image bottom).


Features: embryonic disc, primitive node, primative streak, primative groove, connecting stalk Alternate View: embryonic disc, probably from from the ventral side. Showing the connecting stalk to the left.


Image source: The Kyoto Collection images are reproduced with the permission of Prof. Kohei Shiota and Prof. Shigehito Yamada, Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Kyoto, Japan for educational purposes only and cannot be reproduced electronically or in writing without permission.

Carnegie Collection

Stage7 bf7.jpg

Surface view of implantation site

Stage7 bf8.jpg

Surface lateral view of implantation site

Stage7 bf6.jpgStage7 bf9.jpg

Photograph

Stage7 bf5.jpg Stage7 bf51.jpg
Stage7 bf52.jpg Stage7 bf53.jpg

Image: Ed Uthman (pathologist in Houston, Texas) section of ectopic (tubal) pregnancy.

Image Links: Original full image | Trilaminar embryo excerpt | Villi excerpt 1 | Villi excerpt 2
Full Image versions: ExtraLarge 1712x1206px | Large 1024x721px | Medium 500x352px | Small 240x169px

Stage 7 Images

Bright Field Images: Stage7-bf1.jpg | Stage7-bf2.jpg | Stage7-bf3.jpg | Stage7-bf4.jpg

Scanning Electron Images: Embryonic Disc 1 | Embryonic Disc 2 | Embryonic Disc 3 | Primitive Streak


Carnegie Stages: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | About Stages | Timeline

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

Cite this page: Hill, M.A. (2024, March 28) Embryology Carnegie stage 7. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Carnegie_stage_7

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G