amnion


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Related to amnion: yolk sac, amnion nodosum

am·ni·on

 (ăm′nē-ən, -ŏn′)
n. pl. am·ni·ons or am·ni·a (-nē-ə)
A tough, thin membrane that forms a sac enclosing the embryo or fetus of a mammal, bird, or reptile. It is filled with a serous fluid in which the embryo or fetus is suspended.

[New Latin, from Greek amneion, variant of amneios, amnion, and from amnion, amnion, both from amnos, lamb; akin to Irish úan, Latin agnus, and Old Church Slavonic agnę, lamb.]

am′ni·ot′ic (-ŏt′ĭk), am′ni·on′ic (-ŏn′ĭk) adj.

amnion

(ˈæmnɪən)
n, pl -nions or -nia (-nɪə)
(Zoology) the innermost of two membranes enclosing an embryonic reptile, bird, or mammal. See also chorion
[C17: via New Latin from Greek: a little lamb, from amnos a lamb]

am•ni•on

(ˈæm ni ən)

n., pl. -ni•ons, -ni•a (-ni ə)
the innermost membrane of the sac surrounding the embryo in reptiles, birds, and mammals, enclosing the amniotic fluid.
[1660–70; < Greek amníon, derivative of amnós lamb (see yean)]
am`ni•ot′ic (-ˈɒt ɪk) am`ni•on′ic, adj.

am·ni·on

(ăm′nē-ən)
A sac of thin, tough membrane containing a watery liquid in which the embryo of a reptile, bird, or mammal is suspended. ♦ The watery fluid in the amnion is called amniotic fluid.
amniocentesis, amnion - Amniocentesis is formed by amnion, the innermost membrane enclosing a fetus, and Greek kentesis, "pricking."
See also related terms for mammal.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.amnion - thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals)amnion - thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals)
amniote - any member of the Amniota
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
sac - a structure resembling a bag in an animal
Translations

amnion

[ˈæmnɪən] n (amnions or amnia (pl)) [ˈæmnɪə]amnio

am·ni·on

n. amnios, saco membranoso que envuelve el embrión.
References in periodicals archive ?
"We delivered significant year-over-year revenue growth across both our Advanced Wound Care and Surgical & Sports Medicine portfolios driven by strong sales of our PuraPly and amnion products.
ReNu is a cryopreserved, amniotic suspension allograft, derived from human amnion and amniotic fluid.
If the cervix is favorable for sweeping, insert one finger in the cervix and rotate the finger in a circle to separate the amnion from the cervix.
Placental disorders such as placentomegaly, chronic villitis, acute chorioamnionitis, amnion nodosum, and placenta previa have also been reported in association with chorangiosis (1,3).
Amniotic mesenchymal stem cells (AMSCs) obtained from amnion do not evoke ethical issues, as they do with the embryonic stem cells.
The amnion and chorion primarily produce PG[E.sub.2]; the decidua synthesizes PG[E.sub.2] and PGF2; and the myometrium secretes PGI2.
Acharya et al., "Amnion epithelial cell isolation and characterization for clinical use," Current Protocols in Stem Cell Biology, vol.
Among them, epidural lipomatosis usually occurs in obese people, patients with a history of corticosteroid use, and those with an endocrinopathy.[2] The Kovalevsky or neurenteric canal is defined as a canal connecting the neural tube and archenteron in the embryo, resulting from a persisting abnormal communication between the notochord and yolk sac and the amnion during an early stage of embryonic development.
Here the chorion and amnion are folded upon themselves at the placental margin making the chorionic plate on the foetal side smaller than the basal plate on the maternal side leaving a part of the placenta uncovered at the periphery (1).