ovule

ovule
/ov"yoohl, oh"vyoohl/, n.
1. Bot.
a. a rudimentary seed.
b. the plant part that contains the embryo sac and hence the female germ cell, which after fertilization develops into a seed.
2. Biol. a small egg.
[1820-30; < L ovulum little egg. See OVUM, -ULE]

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▪ plant anatomy
      plant structure that develops into a seed when fertilized. In gymnosperms (gymnosperm) (conifers and allies) the ovules lie uncovered on the scales of the cone. In angiosperms (angiosperm) (flowering plants), one or more ovules are enclosed by the ovary (portion of the carpel, or female reproductive organ). Each ovule is attached by its base to the stalk (funiculus) that bears it. A mature angiosperm ovule consists of a food tissue covered by one or two future seed coats. A small opening (the micropyle) in the integuments at the apex of the ovule permits the pollen tube to enter and discharge its sperm nuclei into the embryo sac, a large oval cell in which fertilization and development occur. Variations in form and position of the ovule are significant in plant classification: orthotropous ovules stand out straight into the cavity of the ovary; campylotropous ovules are at right angles to the funiculus; anatropous ovules are directed back toward the funiculus. Intermediate forms also occur.

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Universalium. 2010.

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  • ovule — ovule …   Dictionnaire des rimes

  • ovule — [ ɔvyl ] n. m. • 1798; lat. sav. ovula, du lat. ovum « œuf » 1 ♦ Bot. Chez les angiospermes, Gamète femelle végétal (⇒ oosphère) qui, après la fécondation, se transforme en graine. Pièces afférentes à l ovule : chalaze, funicule, micropyle,… …   Encyclopédie Universelle

  • Ovule — O vule, n. [Dim. of L. ovum an egg: cf. F. ovule. Cf. {Ovolo}, {Ovulum}.] (Biol.) (a) The rudiment of a seed. It grows from a placenta, and consists of a soft nucleus within two delicate coatings. The attached base of the ovule is the hilum, the… …   The Collaborative International Dictionary of English

  • ovule — 1830, from Fr. ovule, from Mod.L. ovulum, lit. small egg, dim. of L. ovum egg (see OVUM (Cf. ovum)) …   Etymology dictionary

  • ovule — ovulė statusas Aprobuotas sritis farmacinės formos apibrėžtis Vartoti į makštį vietiniam poveikiui sukelti skirtas kietas vienadozis preparatas, gaminamas išliejant ovalia forma veikliosios medžiagos ir tinkamo pagrindo tirpalą ar dispersiją.… …   Lithuanian dictionary (lietuvių žodynas)

  • ovulė — statusas Aprobuotas sritis farmacinės formos apibrėžtis Vartoti į makštį vietiniam poveikiui sukelti skirtas kietas vienadozis preparatas, gaminamas išliejant ovalia forma veikliosios medžiagos ir tinkamo pagrindo tirpalą ar dispersiją.… …   Lithuanian dictionary (lietuvių žodynas)

  • ovule — ovule. См. семязачаток. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • ovulé — ovulé, ée (o vu lé, lée) adj. Se dit d un ovaire ou d une de ses loges qui renferme un ou plusieurs ovules …   Dictionnaire de la Langue Française d'Émile Littré

  • ovule — ► NOUN Botany ▪ the part of the ovary of seed plants that contains the female germ cell and after fertilization becomes the seed. DERIVATIVES ovular adjective. ORIGIN Latin ovulum little egg …   English terms dictionary

  • ovule — [äv′yo͞ol΄, ō′vyo͞ol΄] n. [Fr < ModL ovulum, dim. < L ovum,EGG1] a small egg or seed, esp. one in an early stage of development; specif., a) Bot. a structure in seed plants consisting of a nucellus that contains an embryo sac: it develops… …   English World dictionary

  • Ovule — This article is about the plant structure. For animal ovules, see ovum. Micropyle and Ovular redirect here. For the structure in animals, see Micropyle (zoology). For the shape, see oval. Location of ovules inside a Helleborus foetidus flower… …   Wikipedia

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