chalaza

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Related to chalazal: Chalazal spot

cha·la·za

(kă-lā'ză),
1. Synonym(s): chalazion
2. Suspensory ligament of the yolk in a bird's egg.
[G. hail; a small tubercle, a sty (Galen)]

chalaza

(kə-lā′zə, -lăz′ə)
n. pl. chala·zae (-zē) or chala·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.

cha·la′zal adj.

chalaza

  1. the basal part of the OVULE of a flowering plant to which the FUNICLE is attached, and through which the pollen tube sometimes enters the ovule prior to fertilization.
  2. one of an opposite pair of spiral bands in the white of a bird's egg which suspend the yolk within the shell to prevent it from being damaged.
References in periodicals archive ?
24) there is a massive proximal chalazal region (see perisperm, below).
Dermal cells are enlarged and there is little subdermal tissue, but a long central conducting passage (Zuleitungsbahn) is present, consisting of axially oriented, sometimes darker-staining cells connecting the chalazal vascular supply with the large antipodals (Rudall, 1994).
In several Asparagales there are records of so-called chalazal haustoria, where the developing endosperm invades the lateral parts of the proximal nucellus, breaking down the lateral tissue and leaving a central postament (often with a hypostase: see below).
Both are persistent remains of the nucellus at the chalazal (proximal) end of the embryo sac.
It often leads from the chalazal vascular supply to the embryo sac, often to persistent antipodals, although in Tecophilaea (Fig.
As far as is known, the embryology of Odontostomum resembles that of Cyanastrum, including the elongation of the fertilised embryo sac and the presence of a chalazal tissue with loose strands of cells (Cave, 1952).
Follicles mostly long and slender, sometimes stouter; seeds with chalazal and/or micropylar coma , ecomose, or entire seed testa with long hairs.