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  1. Angiosperms were formerly called Magnoliophyta (/ m æ ɡ ˌ n oʊ l i ˈ ɒ f ə t ə,-ə ˈ f aɪ t ə /). Angiosperms are distinguished from the other seed-producing plants, the gymnosperms, by having flowers, xylem consisting of vessel elements instead of tracheids, endosperm within their seeds, and fruits that completely envelop the seeds.

    • Flowers

      A flower, also known as a bloom or blossom, is the...

    • Monocots

      John Ray (1674), pp. 164, 166 Since this paper appeared a...

    • Wolffia Arrhiza

      Wolffia arrhiza is a species of flowering plant known by the...

    • Description
    • Taxonomy
    • Gallery of Photos
    • Diversity
    • Reproduction
    • Uses

    1.1. Angiosperm Derived Characteristics

    Angiosperms differ from other seed plants in several ways, described in the table below. These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants, and the most commercially important group to humans.

    1.2. Vascular Anatomy

    Angiosperm stems are made up of seven layers as shown on the right. The amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms. In the dicotyledons, the vascular bundles of the stem are arranged such that the xylem and phloem form concentric rings. The bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissu...

    1.3. Reproductive Anatomy

    The characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species. The function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally on a shoot or from the axil of a leaf (where the petiole attaches to the stem). Occasionally, as in violets, a...

    2.1. History of Classification

    The botanical term "angiosperm", from Greek words angeíon (ἀγγεῖον 'bottle, vessel') and spérma (σπέρμα 'seed'), was coined in the form "Angiospermae" by Paul Hermann in 1690 but he used this term to refer to a group of plants which form only a subset of what today are known as angiosperms. Hermannn's Angiospermae including only flowering plants possessing seeds enclosed in capsules, distinguished from his Gymnospermae, which were flowering plants with achenial or schizo-carpic fruits, the wh...

    2.2. Modern Classification

    There are eight groups of living angiosperms: 1. Basal angiosperms (ANA: Amborella, Nymphaeales, Austrobaileyales) 1.1. Amborella, a single species of shrub from New Caledonia; 1.2. Nymphaeales, about 80 species,water lilies and Hydatellaceae; 1.3. Austrobaileyales, about 100 speciesof woody plants from various parts of the world 2. Core angiosperms (Mesangiospermae) 2.1. Chloranthales, 77 known speciesof aromatic plants with toothed leaves; 2.2. Magnoliids, about 10,000 speci...

    A poster of twelve different species of flowers of the family Asteraceae. https://handwiki.org/wiki/index.php?curid=1596958
    Lupinus pilosus. https://handwiki.org/wiki/index.php?curid=1419043
    Bud of a pink rose. https://handwiki.org/wiki/index.php?curid=1269816

    The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss and 11,000 species of pteridophytes, showing that flowering plants are much more diverse. The number of families in APG (1998) was 462. In APG II (2003) it is not settled; at maximum it is 457, but within t...

    5.1. Fertilisation and Embryogenesis

    Double fertilization refers to a process in which two sperm cells fertilise cells in the ovule. This process begins when a pollen grain adheres to the stigma of the pistil (female reproductive structure), germinates, and grows a long pollen tube. While this pollen tube is growing, a haploid generative cell travels down the tube behind the tube nucleus. The generative cell divides by mitosis to produce two haploid (n) sperm cells. As the pollen tube grows, it makes its way from the stigma, dow...

    5.2. Fruit and Seed

    As the development of the embryo and endosperm proceeds within the embryo sac, the sac wall enlarges and combines with the nucellus (which is likewise enlarging) and the integument to form the seed coat. The ovary wall develops to form the fruit or pericarp, whose form is closely associated with type of seed dispersal system. Frequently, the influence of fertilisation is felt beyond the ovary, and other parts of the flower take part in the formation of the fruit, e.g., the floral receptac...

    5.3. Meiosis

    Like all diploid multicellular organisms that use sexual reproduction, flowering plants generate gametes using a specialised type of cell division called meiosis. Meiosis takes place in the ovule—a structure within the ovary that is located within the pistil at the centre of the flower (see diagram labeled "Angiosperm lifecycle"). A diploid cell (megaspore mother cell) in the ovule undergoes meiosis (involving two successive cell divisions) to produce four cells (megaspores) with haploid nucl...

    Agriculture is almost entirely dependent on angiosperms, which provide virtually all plant-based food, and also provide a significant amount of livestock feed. Of all the families of plants, the Poaceae, or grass family (providing grains), is by far the most important, providing the bulk of all feedstocks (rice, maize, wheat, barley, rye, oats, pea...

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  3. en.wikipedia.org › wiki › MagnoliaMagnolia - Wikipedia

    Description. An anatomical diagram of the flower of Magnolia biondii. Magnolia seeds and fruit on a tree in northern Argentina. Magnolias are spreading evergreen or deciduous trees or shrubs characterised by large fragrant flowers, which may be bowl-shaped or star-shaped, in shades of white, pink, purple, green, or yellow.

  4. Magnoliopsida is a valid botanical name for a class of flowering plants. [1] . By definition the class will include the family Magnoliaceae, but its circumscription can otherwise vary, being more inclusive or less inclusive depending upon the classification system being discussed. Magnolia flowers. Classification. Cronquist and Takhtajan systems.

  5. The characteristic features of the phylum (division) of Magnoliophyta are: (1) ovules are enclosed in a more or less completely closed cavity formed by one or by several to many separate or united carpels; (2) pollen grains are deposited not directly on the micropyle...

  6. May 3, 2017 · Chapter 15. Magnoliophyta (I) The Division Magnoliophyta in the Kingdom Plantae comprises those species of plants that were formerly classified as angiosperms and are known widely as the flowering plants.

  7. May 14, 2018 · Magnoliophyta (măg´nōlēŏf´ətə), division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms [1]. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).

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