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The region at the base of the nucellus of an ovule; gives rise to the integuments.
(cell and molecular biology)
One of the paired, spiral, albuminous bands in a bird's egg that attach the yolk to the shell lining membrane at the ends of the egg.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the basal part of the ovule where the seed stalk attaches the ovule to the placenta.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
3H), whereas the three antipodal cells at the chalazal end were ephemeral and degenerated soon after fertilization.
gnemon, the functional female gametophyte consists of an enlarged, vacuolate micropylar region and a constricted, densely cytoplasmic chalazal region [ILLUSTRATION FOR FIGURE 3H OMITTED].
Usually near the chalazal megaspore developed into the functional megaspore while the other three megaspores were eventually degenerated (Fig.
The raphe is large and expanded at the chalazal end of the seed, a hypostase is present, endosperm is apparently free nuclear (Biradar and Mahabale, 1976), and the cotyledons of the embryo are straight.
Only one megaspore functions and it is always one of the two larger chalazal members of the tetrad (Fig.
intybus, the chalazal megaspore of the linear- shaped tetrad gives rise to form Polygonum type of embryo sacasdescribedformorethan70%ofangiosperm (Maheshwari, 1950; Batygina, 1987).
the number of cell layers in the chalazal region and the free
Seeds without tails (0); seed with tails (expanded portion of testa at hilum and chalazal ends) (1) 85.
During the early apomeiotic prophase, vacuoles accumulate in the chalazal region of the MMC, the nucleus moves to the center of the MMC, and callose, which normally envelops sexual MMCs during meiosis (Rodkiewicz, 1970), is generally absent (restricted to the wall of the MMC closest to the micropyle when present).
Fruit mostly a pair of ventrally dehiscent follicles (often only one due to abortion) (rarely a capsule), with small seeds with a micropylar coma, rarely with a chalazal coma or ecomose (fruits in Rauvolfioideae drupes, berries, follicles, or capsules; seeds usually ecomose, naked, winged, or arillate).