In early fetal development, the ventral cloaca (the precursor of the fetal bladder) is connected to the allantois
via the urachus.
In the normal embryologic development of the urogenital system, the cranial part of the urogenital sinus is continuous with the allantois
, developing into the bladder and pelvic urethra; the bladder dome, posterior walls and part of lateral walls, normally arise from surrounding urogenital sinus mesenchyme.
Key words or phrases include chorion, allantois
, yolk sac, amnion, placenta, and umbilical cord.
Derived from the fetal allantois
, it provides a rich source of multipotent stem cells, including [CD34.
is an endermal diverticulum that communicates with the cloaca (hind-gut).
Differences in sialic acid-galactose linkages in the chicken egg amnion and allantois
influence human influenza virus receptor specificity and variant selection.
2] muscle, metanephros, epithelial tissue, fetal membranes, connective tissue, nervous tissue, allantois
, bone marrow, olfactory bulb) Developmental 363 4.
The intra-embryonic cloaca, destined to become the bladder, is connected to the extra-embryonic allantois
derived from the caudal end of the yolk sac through the urachus.
Underdeveloped trophoblast, precocious regression of the yolk sac and/or a failure of the allantois
and vasculature to develop may delay attachment and placentation and, if threshold for survival is not attained, such events will likely be lethal.
The chorioallantoic membrane develops from two extraembryonic structures: the chorion and allantois
The placentas of eutherian mammals consist of two extra-embryonic membranes; that is, the allantois
and the chorion.
Stage 1 ends when the allantois
, or fetal membranes, are pushed through the cervix by the advancing fetus and rupture, releasing amniotic fluid (breaking water).
Blood Vessels Number, Endothelial Vascular Growth Factor, Induced Nitric Oxide Synthase and Endothelial Nitric Oxide Synthase Expression in the Ovine Allantois
Both the trophoblast and the allantois
undergo a phase of elongation similar to what occurs in other ruminants (Drion et al.