Acotyledon

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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 ]

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<span class="mw-page-title-main">Flower</span> Reproductive structure in flowering plants

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Microgreens are vegetable greens harvested just after the cotyledon leaves have developed with one set of true leaves. They are used as a visual, flavor and texture enhancement. Microgreens are used to add sweetness and spiciness to foods. Microgreens are smaller than “baby greens” because they are harvested soon after sprouting, rather than after the plant has matured to produce multiple leaves.

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<span class="mw-page-title-main">Monocotyledon reproduction</span>

The monocots are one of the two major groups of flowering plants, the other being the dicots. In order to reproduce they utilize various strategies such as employing forms of asexual reproduction, restricting which individuals they are sexually compatible with, or influencing how they are pollinated. Nearly all reproductive strategies that evolved in the dicots have independently evolved in monocots as well. Despite these similarities and their close relatedness, monocots and dicots have distinct traits in their reproductive biologies.

References

  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