chorion


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Related to chorion: chorion laeve, chorion frondosum

chorion

 [kor´e-on]
an extraembryonic fetal membrane, composed of trophoblast lined with mesoderm; it develops villi, becomes vascularized, and forms the fetal part of the placenta.
chorion frondo´sum the placental part of the chorion; it is covered by villi.
chorion lae´ve the nonvillous, membranous part of the chorion.

cho·ri·on

(kō'rē-on),
The outermost fetal membrance in human embryos, the villous part of which becomes the fetal part of the placenta.
Synonym(s): membrana serosa (1)
[G. chorion, membrane enclosing the fetus]

chorion

(kôr′ē-ŏn′)
n.
The outer membrane enclosing the embryo in reptiles, birds, and mammals. In placental mammals it contributes to the development of the placenta.

cho′ri·on′ic (-ŏn′ĭk) adj.

cho·ri·on

(kōr'ē-on)
The multilayered, outermost fetal membrane consisting of extraembryonic somatic mesoderm, trophoblast, and, on the maternal surface, its villi are bathed by maternal blood; as pregnancy progresses, part of the villous chorion becomes the fetal part of placenta.
Synonym(s): membrana serosa (1) .
[G. chorion, membrane enclosing the fetus]

chorion

The outer of the two membranes that enclose the embryo. The inner is called the amnion.

chorion

  1. the superficial outer coat of the insect egg which is noncellular and secreted by the ovary around the ovum.
  2. an embryonic membrane of AMNIOTES formed from an outer ectodermal layer (see ECTODERM and an inner mesodermal layer (see MESODERM). see AMNION. In birds and mammals it forms the outer membrane covering the amniotic cavity, and in mammals the mesodermal component of the chorion fuses with the allantois to form the chorioallantoic PLACENTA. Here the chorion develops finger-like outgrowths, the chorionic villi, which project into blood spaces in the uterus of the mother. see CHORIONIC BIOPSY.

Chorion

The outermost membrane of the sac enclosing the fetus.
Mentioned in: Prenatal Surgery
References in periodicals archive ?
(2016), the methodology for toxicity tests employing zebrafish embryos varies greatly between laboratories, with differences in the strain of fish used, timing and frequency of exposure, status of the chorion, exposure apparatus, endpoints measured, and scoring of phenotypic alterations.
In the current study, the researchers prospectively examined chorion membrane samples to identify a pattern of bacterial presence and association with chorion thinning.
Our results suggest that insecticides, specifically bifenthrin, beta-cyfluthrin, and beta-cyfluthrin + acephate, may have the ability to penetrate the chorion of southern green stink bug egg masses.
Pacific Northwest that hatches from the chorion before metamorphosing, similar to what has been reported for M.
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Chorion said the little wooden boy, created by Enid Blyton in 1949, will expand into Spain and Canada as the firm boosts the character's global merchandising.
Chorion have the rights to the literary estates of crime authors Agatha Christie and Raymond Chandler, as well as the children's favourites.
During this time, the chorion of the conceptus produces an LH-like hormone called equine chorionic gonadotropin (eCG).
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Nicholas James - chief executive of Chorion, which owns the rights to the characters - said, 'We are delighted to be working with Five to bring yet another brand with a huge British literary heritage to new audiences.'
Bob the Builder missed out on hiring the Mr Men today after his owner pulled out of making a takeover offer for children's entertainment group Chorion.
The egg chorion surface showed a chorionic pattern resulting in irregular hexagonal patterns There were 18-19 short pipe micropylar projections mounted at the anterior pole.