cotyledon

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Related to Cotyledons: angiosperm, Monocotyledons, Dicotyledons

cotyledon

 [kot″ĭ-le´don]
1. any subdivision of the uterine surface of the placenta.
2. irregular convex areas on the chorionic surface of the placenta, consisting of two or more stem villi and their many branch villi; by the end of the fourth month the decidua basalis is almost entirely replaced by the cotyledons.

cot·y·le·don

(kot'i-lē'don),
1.
2. In plants, a seed leaf, the first leaf to grow from a seed.
3. A placental unit.
[G. kotylēdon, any cup-shaped hollow]

cotyledon

(kŏt′l-ēd′n)
n.
1. Botany A leaf of the embryo of a seed plant, which upon germination either remains in the seed or emerges, enlarges, and becomes green. Also called seed leaf.
2. Anatomy One of the lobules constituting the uterine side of the mammalian placenta, consisting mainly of a rounded mass of villi.

cot′y·le′don·ar′y (-ēd′n-ĕr′ē), cot′y·le′don·al (-ēd′n-əl)(-ēd′n-əs), cot′y·le′do·nous (-ēd′n-əs) adj.

cot·y·le·don

(kot'i-lē'dŏn)
1. In plants, a seed leaf, the first leaf to grow from a seed.
2. Irregular convex area of the fetal part of the placenta composed of stem villi.
[G. kotylēdon, any cup-shaped hollow]

cotyledon

  1. a part of the plant embryo in the form of a specialized seed leaf that can be thin and papery, as in the castor oil plant, or can act as a storage organ, as in the broad bean, absorbing food from the endosperm. Sometimes it also functions as a leaf after EPIGEAL germination, as in the runner bean. Some ANGIOSPERMS have one cotyledon per seed (MONOCOTYLEDONS) while others have two (DICOTYLEDONS).
  2. a part of the mammalian placenta on which a tuft of villi occurs, particularly in ruminants.
References in periodicals archive ?
During the initiation phase, swelling of the explants was observed after six weeks of culture in induction medium and type II calli appeared on the surface of the immature cotyledons (Fig.
Examination of placenta especially shape, measuring placental weight and observation of number of cotyledons of placenta was carried out and photographed by digital camera.
In stone pine, although micropropagation by organogenesis from cotyledons already has an advanced protocol (NANDWANI; KUMARIA; TANDON, 2001; ALONSO et al., 2006), the rooting of explants still needs to be improved (SUL; KORBAN, 2004).
Generally, Meliaceae species have achieved embryogenic callus from cotyledons under the combination of NAA (3 mg [l.sup.-1]) and BAP (1 mg [l.sup.-1]), as indicated by Sharry and Teixeira (2006).
Feeding Experiment of the Labelled (Wyerone and Dihydrowyerone) into the Induced Cotyledons to Produce Wyerone Epoxide.
Fresh organs (cotyledons, hypocotyls or radicles) were ground at 4oC in 0.1 M sodium borate buffer (pH 8.8).
The cotyledons (Figure 1B and C) are thin, green, petiolated and leaf-like; the leaf blade shows morphological diversity varying from ovate to parabolic, apex obtuse or roundish, base obtuse or straight, margin sinuate or crenate, and trinervous.
The cotyledons showed no significant differences between any of the treatments and the fungicide or the untreated (data not shown).