Connecting stalk
Connecting stalk | |
---|---|
Details | |
Precursor | Extraembryonic mesoderm |
Identifiers | |
Latin | pedunculus connectans |
TE | stalk_by_E5.11.3.1.1.0.4 E5.11.3.1.1.0.4 |
Anatomical terminology |
The connecting stalk, or body stalk also known as the allantoic stalk is a yolk sac diverticulum,[1][2] that by the third week of development connects the embryo to its shell of trophoblasts. 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 hindgut. Progressive expansion of the amnion from the umbilical ring (surrounding the roots of the vitelline duct and connecting stalk) creates a tube of amniotic membrane. The amniotic membrane and its contents form the umbilical cord that connects the embryo and the placenta.[3][4]
The connecting stalk is derived from extraembryonic mesoderm.[5] The root of the connecting stalk contains the allantois as a diverticulum of hindgut endoderm.[6]
Anomalies are usually referred to as body stalk anomalies and occur in approximately 1 in 15,000 births.[7] They are due to defects in the formation of the cephalic, caudal, and lateral embryonic body folds,[8] that result in a reduced or absent umbilical cord.[9]
Additional images
- Human embryo—length, 2 mm. Dorsal view, with the amnion laid open. X 30.
- Human embryo of 2.6 mm.
- Model of human embryo 1.3 mm. long.
- Section through ovum imbedded in the uterine decidua.
- Embryo between eighteen and twenty-one days.
References
- ↑ M. W. Rana (28 July 1998). Human embryology made easy. CRC Press. pp. 66–. ISBN 978-90-5702-545-7. Retrieved 22 May 2011.
- ↑ Arthur Robinson (1913). Cunningham's Textbook of Anatomy. William Wood. p. 54.
- ↑ Sadler, T. W. (2010). Langman's medical embryology (11th ed.). Philadelphia: Lippincott William & Wilkins. pp. 64–65. ISBN 9780781790697.
- ↑ Larsen's Embryology, 5th edition, p138.
- ↑ Schoenwolf, Gary C.; Bleyl, Steven B.; Brauer, Philip R.; Francis-West, Philippa H. (2012-05-07). Larsen's Human Embryology: with STUDENT CONSULT Online Access. Elsevier Health Sciences. p. 57. ISBN 9781455727919.
- ↑ Larsen, William J. (2001). Human embryology (3rd ed.). New York: Churchill Livingstone. p. 138. ISBN 0443065837.
- ↑ Asim Kurjak (30 June 2013). Donald School Textbook of Transvaginal Sonography. JP Medical Ltd. p. 28. ISBN 978-93-5090-473-2.
- ↑ Diana W. Bianchi; Timothy M. Crombleholme; Mary E. D'Alton (1 January 2000). Fetology: Diagnosis & Management of the Fetal Patient. McGraw Hill Professional. ISBN 978-0-8385-2570-8.
- ↑ Kocherla, K; Kumari, V; Kocherla, PR (January 2015). "Prenatal diagnosis of body stalk complex: A rare entity and review of literature". The Indian Journal of Radiology & Imaging. 25 (1): 67–70. doi:10.4103/0971-3026.150162. PMC 4329692. PMID 25709170.
External links
- Swiss embryology (from UL, UB, and UF) hdisqueembry/triderm0