dicotyledon

dicotyledon
/duy kot'l eed"n, duy'kot l-/, n. Bot.
any angiospermous plant of the class (or subclass) Dicotyledoneae, producing seeds with two cotyledons and having an exogenous manner of growth. Cf. monocotyledon.
[1720-30; < NL Dicotyledones a pre-Linnean grouping of such plants. See DI-1, COTYLEDON]

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plant

      any member of the flowering plants, or angiosperms, that has a pair of leaves, or cotyledons, in the embryo of the seed. There are about 175,000 known species of dicots. Most common garden plants, shrubs and trees, and broad-leafed flowering plants such as magnolias, roses, geraniums, and hollyhocks are dicots.

      Dicots typically also have flower parts (sepals, petals, stamens, and pistils) based on a plan of four or five, or multiples thereof, although there are exceptions. The leaves are net-veined in most, which means the vessels that conduct water and food show a meshlike pattern. In the stems the vessels are usually arranged in a continuous ring near the stem surface. About 50 percent of all dicot species are woody; they show an annual increase in stem diameter as a result of the production of new tissue by the cambium, a layer of cells that remain capable of division throughout the life of these plants. Branching of stems is common, as are taproots. The microscopic pores (stomates) on the leaf surfaces are usually scattered and are in various orientations. The pollen grains typically have three germinal furrows or pores (tricolpate condition), except in the more primitive families.

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Universalium. 2010.

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  • dicotyledon — di*cot y*le don (d[ i]*k[o^]t [i^]*l[=e] d[u^]n), n. [Pref. di + cotyledon.] (Bot.) A plant whose seeds divide into two seed lobes, or cotyledons, in germinating. Syn: dicot, dicotyl. [1913 Webster] …   The Collaborative International Dictionary of English

  • dicotyledon — ► NOUN ▪ a plant with an embryo bearing two cotyledons (seed leaves) …   English terms dictionary

  • dicotyledon — [dī΄kät΄ə lēd′ n] n. Bot. any of a class (Magnoliopsida) of angiosperms, as oak trees, legumes, and cactuses, with an embryo containing two cotyledons (seed leaves), characterized by net veined leaves, flower parts in fours or fives, and the… …   English World dictionary

  • dicotyledon — UK [daɪˌkɒtɪˈliːd(ə)n] / US [daɪˌkɑt(ə)lˈɪd(ə)n] noun [countable] Word forms dicotyledon : singular dicotyledon plural dicotyledons biology a plant that produces seeds that develop into two leaves …   English dictionary

  • dicotyledon — noun Etymology: New Latin Date: circa 1727 any of a class or subclass (Magnoliopsida or Dicotyledoneae) of angiospermous plants that produce an embryo with two cotyledons and usually have floral organs arranged in cycles of four or five and… …   New Collegiate Dictionary

  • Dicotyledon — Dicot redirects here. For the band, see Dicot (band). Magnoliopsida (Dicotyledons) Magnolia flower Scientific classification …   Wikipedia

  • dicotyledon — noun a) A plant whose seedling has two cotyledons. b) Any plant in what used to be the Dicotyledones. Syn: dicot, magnoliopsid …   Wiktionary

  • dicotyledon — Plant (shrub, herb, or tree) whose seeds consist of two cotyledons, i.e., the primary or rudimentary leaf of the embryo of seed plants. * * * di·cot·y·le·don (di kot″əl eґdon) [di + cotyledon] a flowering plant with embryos having two… …   Medical dictionary

  • dicotyledon — Synonyms and related words: Angiospermae, Cycadales, Ginkgoales, Gnetales, Monocotyledones, Pinales, amphibian, angiosperm, angiosperms, annual, aquatic plant, biennial, conifers, cosmopolite, cutting, cycads, deciduous plant, dicot, dicotyledons …   Moby Thesaurus

  • dicotyledon — di·cot·y·le·don || ‚daɪkÉ’tɪ liːdÉ™n n. plant with two seed leaves (Botany) …   English contemporary dictionary

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