allantois


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Related to allantois: yolk sac, urachus, Vitelline duct

al·lan·to·is

 (ə-lăn′tō-ĭs)
n. pl. al·lan·to·i·des (ăl′ən-tō′ĭ-dēz′)
A membranous sac that develops from the posterior part of the digestive tract in the embryos of mammals, birds, and reptiles. It is important in the formation of the umbilical cord and placenta in mammals. Also called allantoid.
[New Latin allāntois, variant of allāntoīdēs, from Greek allāntoeidēs, sausage-shaped : allās, allānt-, sausage (perhaps from Greek dialectal (Magna Graecia) *allāwent-, (sausage) seasoned with garlic, from *allā-, garlic, of Italic origin; akin to Latin ālium, garlic; see allium) + -oeidēs, -oid.]
al′lan·to′ic (ăl′ən-tō′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

allantois

(ˌælənˈtəʊɪs; əˈlæntɔɪs)
n
(Zoology) a membranous sac growing out of the ventral surface of the hind gut of embryonic reptiles, birds, and mammals. It combines with the chorion to form the mammalian placenta
[C17: New Latin, irregularly from Greek allantoeidēs sausage-shaped, allantoid]
allantoic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

al•lan•to•is

(əˈlæn toʊ ɪs, -tɔɪs)

n., pl. al•lan•to•i•des (ˌæl ənˈtoʊ ɪˌdiz)
a nourishing membrane surrounding the embryo, between the amnion and chorion, in birds and reptiles developing as a sac from the hindgut and in mammals as an inner layer of the placenta.
[1640–50; < New Latin < Greek allantoeidḗs (see allantoid).]
al`lan•to′ic, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

al·lan·to·is

(ə-lăn′tō-ĭs)
A membranous sac that grows out of the lower end of the alimentary canal in embryos of reptiles, birds, and mammals. In mammals, the blood vessels of the allantois develop into the blood vessels of the umbilical cord.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.allantois - the vascular fetal membrane that lies below the chorion and develops from the hindgut in many embryonic higher vertebrates (reptiles, birds and mammals)allantois - the vascular fetal membrane that lies below the chorion and develops from the hindgut in many embryonic higher vertebrates (reptiles, birds and mammals)
mammal, mammalian - any warm-blooded vertebrate having the skin more or less covered with hair; young are born alive except for the small subclass of monotremes and nourished with milk
fetal membrane - any membrane that functions for the protection or nourishment or respiration or excretion of a developing fetus
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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References in periodicals archive ?
Erroneous access into the allantois was excluded by the color and viscosity of the sample (10).
Inflammation-mediated fetal injury by maternal granulocyte-colony stimulating factor and high-dose intra-amniotic endotoxin in the caprine model/Maternal granulosit koloni stimulan faktor ve yuksek doz intra-amniyotik endotoksin ile enflamasyon aracili fetal beyin hasari keci modeli
The urachus, a midline tubular structure, represents an embryologic remnant of the allantois, the cephalic extension of cloaca that connects the anterior dome of the bladder and the umbilicus.
Mucinous Cystadenoma of the Urachus and Review of Current Classification of Urachal Mucinous Cystic Neoplasms
The CAM consists of two extra-embryonic membranes: the chorion and the allantois, which fuse together on embryonic day (ED) 4.
Preclinical Alternative Model for Analysis of Porous Scaffold Biocompatibility Applicable in Bone Tissue Engineering
Table 1: Day of first detection of ultrasonographically First day detected Characteristic Mean Range (days) (days) Embryo proper 20.3 19 to 24 Heartbeat 20.9 19 to 24 Allantois 23.2 22 to 25 Spinal cord 29.1 26 to 33 Forelimb buds 29.1 28 to 31 Amnion 29.5 28 to 33 Eye orbit 30.2 29 to 33 Hindlimb buds 31.2 30 to 33 Placentomes 35.2 33 to 38 Split hooves 44.6 42 to 49 Foetal movement 44.8 42 to 50 Ribs 52.8 51 to 55
Reproductive Ultrasonography in Bovine Practice - A Review
Also called the median umbilical ligament, the urachus is a vestigial remnant of two embryonic structures: the cloaca and the allantois [1].
An Adult with a Remnant Urachus Anomaly Diagnosed in the Emergency Department
Theurachusisanembryologicalremnantthatoriginatesfrom the involution of the allantois and cloaca, extending from the umbilicus to the bladder dome.
Urachal Adenocarcinoma: A Case Report with Key Imaging Findings and Radiologic-Pathologic Correlation
Urachus is a fibrous remnant of the urogenital sinus and allantois. Generally, the urachus involutes after the third trimester and forms the medium umbilical ligament.
Urachal Carcinoma with Peritoneal Dissemination Treated with Chemotherapy and Surgical Resection Leading to Prolonged Survival with No Recurrence
Osmoregulation by avian embryos: The allantois functions like a toad's bladder.
Physico-chemical properties of late-incubation egg amniotic fluid and a potential in ovo feed supplement
The urachus is a tubular structure that connects the bladder to the allantois in the embryonic development, involuting after the third trimester, into a fibromuscular tract or closed canal between the dome of urinary bladder and the umbilicus.
Urachal Tumor: A Case Report of an Extremely Rare Carcinoma
The allantois forms the basis of the umbilical cord.
Lasting impact of an ephemeral organ: the role of the placenta in fetal programming

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