Zoology: General

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chorion

A Dictionary of Zoology | 1999 | | Copyright

chorion
1. The outer cellular layer of the embryo sac of reptiles, birds, and mammals. It consists of two epithelial layers, an ectoderm surrounding a mesoderm layer. In mammals, the outer epithelium (trophoblast) of the chorion forms the placenta, maintaining close contact with the maternal tissues. See also AMNION.

2. The structurally complex outer coat of an insect egg, which is often externally patterned, frequently reflecting the pattern of follicle cells in the ovary which laid it down.

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chorion

A Dictionary of Biology | 2004 | Copyright

chorion
1. A membrane enclosing the embryo, yolk sac, and allantois of reptiles, birds, and mammals. In mammals a section of the chorion becomes the embryonic part of the placenta. See extraembryonic membranes.

2. The protective shell of an insect egg, produced by the ovary. It is pierced by a small pore (micropyle) that allows the entry of spermatozoa for fertilization. See also egg membrane.

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"chorion." A Dictionary of Biology. 2004. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O6-chorion.html

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chorion

A Dictionary of Nursing | 2008 | Copyright

chorion (kor-iŏn) n. the embryonic membrane that totally surrounds the embryo from the time of implantation.
—chorionic adj.

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chorionic villi

A Dictionary of Nursing | 2008 | Copyright

chorionic villi pl. n. see villus.

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Free newspaper and magazine articles

	Chorion heads for the provinces. Newspaper article from: Sunday Business (London, England); 7/16/2000
	Noddy's owner Chorion in talks to buy Mr Men rights amid takeover... Newspaper article from: The Birmingham Post (England); 12/16/2003
	Tiger club to have cubs; Roaring success: Chorion is opening two more outlets... Newspaper article from: The Birmingham Post (England); 3/13/2002