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 (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.


n, pl -zas or -zae (-ziː)
1. (Zoology) one of a pair of spiral threads of albumen holding the yolk of a bird's egg in position
2. (Botany) the basal part of a plant ovule, where the integuments and nucellus are joined
[C18: New Latin, from Greek: hailstone]
chaˈlazal adj


(kəˈleɪ zə)

n., pl. -zas, -zae (-zē).
1. one of the two albuminous twisted cords fastening an egg yolk to the shell membrane.
2. the point of an ovule or seed where the integuments are united to the nucellus.
[1695–1705; < New Latin < Greek: hail, lump]
cha•la′zal, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.chalaza - basal part of a plant ovule opposite the micropyle; where integument and nucellus are joined
ovule - a small body that contains the female germ cell of a plant; develops into a seed after fertilization
plant part, plant structure - any part of a plant or fungus
2.chalaza - one of two spiral bands of tissue connecting the egg yolk to the enclosing membrane at either end of the shell
egg - animal reproductive body consisting of an ovum or embryo together with nutritive and protective envelopes; especially the thin-shelled reproductive body laid by e.g. female birds
animal tissue - the tissue in the bodies of animals
References in periodicals archive ?
These cells present cytoplasm that is intensely stained by safranin, Epidermal cells at the base of the funiculus are enlarged radially forming a projection with 5-6 layers of parenchyma cells (see Figure 4H) which are not glandular in appearance, The integuments are multi-layered and covered by cuticle, The outer integument consists of 2-4 layers of isodiametric cells that are variable in size, while the inner integument is thicker with multiple layers of cells in the micropyle region, The vascular tissue occurs in the outer integument and extends from the chalaza to the inner integument (see Figure 41).
hilum, strophiole (a crestlike excrescence about the hilum), micropyle (opening through which the pollen tube enters), or chalaza (the region opposite the micropyle, where the integuments and nucellus (central part in which the embryo sac develops) are joined) that either softens, cracks, ruptures, or collapses during treatment (Rolston, 1978, Baskin et al.
The basal part of the tegmen undergoes intercalary growth and vascularization that comes from the chalaza (Figure 4A), characterizing the formation of an endopachychalaza.
Chalaza (keh-laz-eh) The pair of protein bands that hold the yolk in the center of the egg.
Presencia o ausencia de una serie de caracteristicas que son diagnosticas para la especie: hilo seminal, arilo, micropila, rafe, caruncula, chalaza y radicula (Burkart, 1952)
In Aristolochia, it consists of a massive secretion from the funicle plus the chalaza (in A.
Some PG-F9 ovules displayed a single anomalous cell with enlarged nucleus and nucleolus located deep in the chalaza (Fig.