extraembryonic


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Related to extraembryonic: extraembryonic membranes

extraembryonic

 [ek″strah-em″bre-on´ik]
external to the embryo proper, as the extraembryonic coelom or the extraembryonic membranes.

ex·tra·em·bry·on·ic

(eks'tră-em'brē-on'ik),
Outside the embryonic body; for example, the extraembryonic membranes involved with the embryo's protection and nutrition that are discarded at birth.

extraembryonic

/ex·tra·em·bry·on·ic/ (eks″trah-em″bre-on´ik) external to the embryo proper, as the extraembryonic coelom or extraembryonic membranes.

extraembryonic

(ĕk′strə-ĕm′brē-ŏn′ĭk)
adj.
Of or being a structure that is outside the embryo: extraembryonic membranes.

ex·tra·em·bry·on·ic

(eks'tră-em'brē-on'ik)
Outside the body of the embryo; referring, e.g., to membranes providing protection and nutrition but discarded at birth without being incorporated in the body.

extraembryonic

lying outside the embryo, e.g. EMBRYONIC MEMBRANE.

extraembryonic

external to the embryo proper, as the extraembryonic celom or the extraembryonic membranes.

extraembryonic membranes
the fetal membranes, chorion, amnion, allantois, yolk sac; term used mostly in the early embryonic period.
References in periodicals archive ?
A totipotent cell is capable of producing all the tissues of an adult, as well as the extraembryonic tissues produced by embryos--amnion, placenta, etc.
Smad2 signaling in extraembryonic tissues determines anterior-posterior polarity of the early mouse embryo.
At least two mechanistic hypotheses have been used to explain higher embryonic mortality in IVP pregnancies: (a) failure in extraembryonic membrane formation and attachment: suboptimal IVP conditions impair development, leading to conceptus growth retardation, delayed attachment and placentation, further restricting growth, and leading to death for reduced transfer capacity between the embryo and the maternal system (28, 30, 32); and (b) expression of surface antigens from the MHC I complex in the trophoblast of SCNT-derived concepti, which may lead to rejection of the allograft (37).
To avoid the damaging effects of UVR, aquatic broadcast spawning species use a variety of defensive mechanisms including extraembryonic shielding cells, spawning behavior, DNA repair mechanisms, and UV absorbing molecules (Epel et al.
The chorioallantoic membrane develops from two extraembryonic structures: the chorion and allantois.
Erk5 null mice display multiple extraembryonic vascular and embryonic cardiovascular defects.
The differentiation of the embryo into embryonic and extraembryonic tissues is a complex process (Figures 15-3 and 15-4).
Dynamic study of the extraembryonic vascular network of the chick embryo by fractal analysis.
As such, the presence of extraembryonic membranes is necessary, not in the sense that it follows directly from the laws of chemistry; rather, they are necessary if the embryo is going to survive.
Oct-4 transcription factor is differentially expressed in the mouse embryo during establishment of the first two extraembryonic cell lineages involved in implantation.
Smad5 knockout mice die at mid-gestation due to multiple embryonic and extraembryonic defects.
In the normal course of events, the bowel of the developing embryo herniates into the extraembryonic coelomic cavity, where it makes a 90[degrees] cephalocaudal rotation before returning into the intra-abdominal cavity and completing a 270[degrees] counterclockwise rotation.