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Acotyledon

Acotyledon is used to refer to seed plants or spermatophytes that lack cotyledons, such as orchids and dodder. Orchid seeds are tiny with underdeveloped embryos. They depend on mycorrhizal fungi for their early nutrition so are myco-heterotrophs at that stage.[citation needed]

Although some authors, especially in the 19th century and earlier, use the word acotyledon to include plants which have no cotyledons because they lack seeds entirely (such as ferns and mosses),[1][2][3] others restrict the term to plants which have seeds but no cotyledons.[4]

Flowering plants or angiosperms are divided into two large groups. Monocotyledons or monocots have one seed lobe, which is often modified to absorb stored nutrients from the seed so never emerges from the seed or becomes photosynthetic. Dicotyledons or dicots have two cotyledons and often germinate to produce two leaf-like cotyledons. Conifers and other gymnosperms lack flowers but may have two or more cotyledons in the seedling.[citation needed]

References edit

  1. ^ "acotyledon", Webster's Revised Unabridged Dictionary, 1913, archived from the original on 2012-07-10
  2. ^ William Thomas Brande (1842), "acotyledons", A Dictionary of Science, Literature, & Art, p. 11
  3. ^ John Lindley, Thomas Moore, ed. (1866), "acotyledons", The treasury of botany
  4. ^ Noah Webster (1828), "acotyledon", American Dictionary of the English Language


acotyledon, mite, genus, acaridae, mite, used, refer, seed, plants, spermatophytes, that, lack, cotyledons, such, orchids, dodder, orchid, seeds, tiny, with, underdeveloped, embryos, they, depend, mycorrhizal, fungi, their, early, nutrition, myco, heterotrophs. For the mite genus Acaridae see Acotyledon mite Acotyledon is used to refer to seed plants or spermatophytes that lack cotyledons such as orchids and dodder Orchid seeds are tiny with underdeveloped embryos They depend on mycorrhizal fungi for their early nutrition so are myco heterotrophs at that stage citation needed Although some authors especially in the 19th century and earlier use the word acotyledon to include plants which have no cotyledons because they lack seeds entirely such as ferns and mosses 1 2 3 others restrict the term to plants which have seeds but no cotyledons 4 Flowering plants or angiosperms are divided into two large groups Monocotyledons or monocots have one seed lobe which is often modified to absorb stored nutrients from the seed so never emerges from the seed or becomes photosynthetic Dicotyledons or dicots have two cotyledons and often germinate to produce two leaf like cotyledons Conifers and other gymnosperms lack flowers but may have two or more cotyledons in the seedling citation needed References edit acotyledon Webster s Revised Unabridged Dictionary 1913 archived from the original on 2012 07 10 William Thomas Brande 1842 acotyledons A Dictionary of Science Literature amp Art p 11 John Lindley Thomas Moore ed 1866 acotyledons The treasury of botany Noah Webster 1828 acotyledon American Dictionary of the English Language nbsp This plant morphology article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Acotyledon amp oldid 1171240374, wikipedia, wiki, book, books, library,

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