Body-stalk
From Wikipedia, the free encyclopedia
| Body-stalk | ||
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| Diagram showing the expansion of amnion and delimitation of the umbilicus. | ||
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| Section through the embryo. | ||
| Gray's | subject #10 53 | |
| Dorlands/Elsevier | s_21/12755040 | |
The caudal end of the embryo is at first connected to the chorion by a band of mesoderm called the body-stalk, but with the formation of the caudal fold the body-stalk assumes a ventral position; a diverticulum of the yolk-sac extends into the tail fold and is termed the hind-gut.
[edit] Additional images
 Human embryo—length, 2 mm. Dorsal view, with the amnion laid open. X 30. |
 Human embryo of 2.6 mm. |
 Diagram showing later stage of allantoic development with commencing constriction of the yolk-sac. |
 Model of human embryo 1.3 mm. long. |
 Section through ovum imbedded in the uterine decidua. |
 Embryo between eighteen and twenty-one days. |
 Human embryo about fifteen days old. Brain and heart represented from right side. Digestive tube and yolk sac in median section. |
[edit] External links
- Swiss embryology (from UL, UB, and UF) hdisqueembry/triderm0
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This developmental biology article is a stub. You can help Wikipedia by expanding it. |
| Mammalian development of embryo and development of fetus (some dates are approximate - see Carnegie stages) |
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| Week 1: Zygote - Morula - Blastula/Blastomere/Blastosphere - Archenteron/Primitive streak - Blastopore - Allantois - Trophoblast (Cytotrophoblast - Syncytiotrophoblast - Gestational sac)
Week 2: Yolk sac - Vitelline duct - Bilaminar disc Week 3: Hensen's node - Gastrula/Gastrulation - Trilaminar embryo Branchial arch (1st) - Branchial pouch - Meckel's cartilage - Somite/Somitomere - Sclerotome - Myotome - Germ layer (Ectoderm, Endoderm, Mesoderm, Chordamesoderm, Paraxial mesoderm, Intermediate mesoderm, Lateral plate mesoderm, Splanchnopleure, Somatopleure) Histogenesis and Organogenesis Uterine support: Placenta - Umbilical cord (Umbilical artery, Umbilical vein, Wharton's jelly) - Amniotic sac (Amnion, Chorion) |
