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Related to chalazal: Chalazal spot


 (kə-lā′zə, -lăz′ə)
n. pl. cha·la·zae (-zē) or cha·la·zas
1. Biology One of two spiral bands of tissue in an egg that connect the yolk to the lining membrane at either end of the shell.
2. Botany The region of an ovule that is opposite the micropyle, where the integuments and nucellus are joined.

[Greek khalaza, hard lump, hailstone.]

cha·la′zal adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
The megaspore tetrads are arranged linearly, and the megaspore at the chalazal end is functional.
Occurring at the chalazal end of the ovule there is a cup-shaped region of thick-walled cells (see Figure 4G).
Seed length was measured from hilar to chalazal end; seed width and thicknesses were taken at the mid portion and the widest part, respectively, of the seed.
Se realizo un corte con bisturi en el extremo chalazal bajo microscopio estereoscopico con aumento de 5X (Severin et al., 2004).
Seeds 4 per fruit, compressed, more or less cuadrangular in outline with a micropilar neck and a chalazal beak, 9-10 mm long, 5-6 mm wide and 1 mm thick.
0,7 mm wide, flattened, not thickened towards the apex, yellowish; anthers linear, subdorsifixed, slightly sagittate, with a thick green connective and dark brown to blackish thecae, pollen yellow; ovary conical, the lower 1/3 (= nectary tissue) sunk into the receptacle, yellowish, nectary tissue orange, the superior part 7 mm long; ovules white, the flat chalazal appendage about half as long as the ovule proper; style ca.
Changes in chalazal cell walls and in the peroxidase enzymes of the crease region during grain development in barley.
We've all heard of physical dormancy, but the discussion in Chapter 3, along with information in a table and a figure, brings all the information together and helps to explain (and us to remember) differences between strophioles or chalazal plugs.
Each megaspore initiates a pattern of free nuclear development, but only the gametophyte located in the most chalazal (basal) position will continue to develop and eventually participate in fertilization [ILLUSTRATION FOR FIGURE 3C OMITTED].