Magnoliophyta (Flowering plants)
Magnolia flower
Scientific classification
Kingdom: Plantae Division: Magnoliophyta
Classes
Magnoliopsida - Dicots Liliopsida - Monocots Magnolia This photo is a part of the Wikipedia:Plant photo collection I. Downloaded URL: http://tencent. ... Wildflowers A flower is the reproductive organ of those plants classified as angiosperms (flowering plants; Division Magnoliophyta). ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Divisions Green algae Land plants (embryophytes) Non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Orders see text Dicotyledons or dicots are flowering plants whose seed contains two embryonic leaves or cotyledons. ... Orders Base Monocots: Acorus Alismatales Asparagales Dioscoreales Liliales Pandanales Family Petrosaviaceae Commelinids: Arecales Commelinales Poales Zingiberales Family Dasypogonaceae Monocotyledons or monocots are a group of flowering plants usually ranked as a class and once called the Monocotyledoneae. ...

The flowering plants (also angiosperms or Magnoliophyta) are one of the major groups of modern plants, comprising those that produce seeds in specialized reproductive organs called flowers, where the ovulary or carpel is enclosed. The other seed plants are called gymnosperms; here the ovule is not enclosed at pollination. Divisions Green algae Land plants (embryophytes) Non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... A SeeD is a term given to mercenaries trained and employed by Balamb Garden in the Final Fantasy VIII video game. ... In biology, an organ (Latin organum: instrument, tool) is a group of tissues, which perform a specific function or group of functions. ... Wildflowers A flower is the reproductive organ of those plants classified as angiosperms (flowering plants; Division Magnoliophyta). ... The spermatophytes comprise those plants that produce seeds. ... Gymnosperms are seed-bearing, vascular plants. ...

History

The botanical term "Angiosperm" (Greek: αγγειον, receptacle, and σπερμα, seed) was coined in the form Angiospermae by Paul Hermann in 1690, as the name of that one of his primary divisions of the plant kingdom, which included flowering plants possessing seeds enclosed in capsules, in contradistinction to his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits—the whole fruit or each of its pieces being here regarded as a seed and naked. The term and its antonym were maintained by Carolus Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any approach to its modern scope only became possible after Robert Brown had established in 1827 the existence of truly naked ovules in the Cycadeae and Coniferae, entitling them to be correctly called Gymnosperms. From that time onwards, so long as these Gymnosperms were, as was usual, reckoned as dicotyledonous flowering plants, the term Angiosperm was used antithetically by botanical writers, but with varying limitation, as a group-name for other dicotyledonous plants. Events Giovanni Domenico Cassini observes differential rotation within Jupiters atmosphere. ... A painting of Carolus Linnaeus Carl Linnaeus, also known after his ennoblement as Carl von Linné   listen?, and who wrote under the Latinized name Carolus Linnaeus (May 23, 1707 – January 10, 1778), was a Swedish botanist who laid the foundations for the modern scheme of taxonomy. ... Robert Brown could be Robert Brown (1773-1858), botanist Robert Brown, Australian politician Robert Brown (born 1921), former English politician Robert Brown (born 1947), Scottish politician Robert Brown, United States politician Robert Brown, theologian and influence on the Congregationalist church Robert Brown (1921-2003), the actor who played M in... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Cycads are an ancient group of seed plants which are characterized by a large crown of compound leaves and a stout trunk. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... Gymnosperms are seed-bearing, vascular plants. ...

The advent in 1851 of Hofmeister's brilliant discovery of the changes proceeding in the embryo-sac of flowering plants, and his determination of the correct relationships of these with the Cryptogamia, fixed the position of Gymnosperms as a class distinct from Dicotyledons, and the term Angiosperm then gradually came to be accepted as the suitable designation for the whole of the flowering plants other than Gymnosperms, and as including therefore the classes of Dicotyledons and Monocotyledons. This is the sense in which the term is nowadays received and in which it is used here. Events January 23 - The flip of a coin determines whether a new city in Oregon is named after Boston, Massachusetts, or Portland, Maine, with Portland winning. ... Divisions Non-seed-bearing plants Equisetophyta Lycopodiophyta Psilotophyta Pteridophyta Superdivision Spermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta The vascular plants are those plants that have specialized cells for conducting water and sap within their tissues, including the ferns, clubmosses, horsetails, flowering plants, conifers and other gymnosperms, but not mosses, algae, and...

Origins

The trend of the evolution of the plant kingdom has been in the direction of the establishment of a vegetation of fixed habit and adapted to the vicissitudes of a life on land, and the Angiosperms are the highest expression of this evolution and constitute the dominant vegetation of the earth's surface at the present epoch. There is no land-area from the poles to the equator, where plant-life is possible, upon which Angiosperms are not found. They occur also abundantly in the shallows of rivers and fresh-water lakes, and in less number in salt lakes and in the sea; such aquatic Angiosperms are not, however, primitive forms, but are derived from immediate land-ancestors. Associated with this diversity of habitat is great variety in general form and manner of growth. The familiar duckweed which covers the surface of a pond consists of a tiny green "thalloid" shoot, one, that is, which shows no distinction of parts—stem and leaf, and a simple root growing vertically downwards into the water. The great forest-tree has a shoot, which in the course perhaps of hundreds of years, has developed a wide-spreading system of trunk and branches, bearing on the ultimate twigs or branchlets innumerable leaves, while beneath the soil a widely-branching root-system covers an area of corresponding extent. Between these two extremes is every conceivable gradation, embracing aquatic and terrestrial herbs, creeping, erect or climbing in habit, shrubs and trees, and representing a much greater variety than is to be found in the other subdivision of seed-plants, the Gymnosperms.

The first evidence of angiosperms appears in the fossil record approximately 140 million years ago, during the Jurassic period (203-135 million years ago). Based on current evidence, it is seems that the ancestors of the angiosperms and the Gnetophytes diverged from one another during the late Triassic (220-202 million years ago). Fossil plants with some identifiable angiosperm characteristics appear in the Jurassic and early Cretaceous (135-65 million years ago), but in relatively few and primitive forms. The great angiosperm radiation, when a great diversity of angiosperms appear in the fossil record, occurred in the mid-Cretaceous (approximately 100 million years ago). By the late Cretaceous, angiosperms appear to have become the predominant group of land plants, and many fossil plants recognizable as belonging to modern families (including beech, oak, maple, and magnolia) appeared. The Jurassic period is a major unit of the geologic timescale that extends from about 200 million years BP at the end of the Triassic to 146 million years BP at the beginning of the Cretaceous. ... taxa: Gnetales Welwitschiales Ephedrales The plant division Gnetophyta or gnetophytes comprise three related families of woody plants grouped in the gymnosperms, a paraphyletic group of seed plant divisions. ... The Triassic is a Geologic period that extends from about 248 to 202 million years (My or megayears) before the present. ... The Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period (about 135 mya) to the beginning of the Paleocene epoch of the Tertiary period (65 mya). ... Species Fagus crenata - Japanese Beech Fagus engleriana - Chinese Beech Fagus grandifolia - American Beech Fagus hayatae - Taiwan Beech Fagus japonica - Japanese Blue Beech Fagus longipetiolata - South Chinese Beech Fagus lucida - Shining Beech Fagus mexicana - Mexican Beech or Haya Fagus orientalis - Oriental Beech Fagus sylvatica - European Beech Beech (Fagus) is a genus... Oakland International Airport is located in Oakland, California and serves the San Francisco Bay Area metro region. ... The MAPLE dedicated isotope-production facility is a current project jointly undertaken by AECL and MDS Nordion. ... This article refers to the plant. ...

Classification

The flowering plants are usually treated as a division, formerly called the Angiospermatophyta or Anthophyta, but now called Magnoliophyta after the type genus Magnolia. Their classification has undergone considerable revision as ideas about their relationships change. The Cronquist system, proposed by Arthur Cronquist in 1981, is still widely used but is no longer believed to reflect phylogeny. A general consensus about how the flowering plants should be arranged has only recently begun to emerge, through the work of the Angiosperm Phylogeny Group, who published an influential reclassification of the angiosperms in 1998. An update incorporating more recent research was published as APG (2003) and is available here Wikipedia Tree of Life/Update of the Angiosperm Phylogeny Group. This article discusses categorisations of organisms. ... Type specimens When a new species is discovered, more important than creating a new and unique name for the species is developing a reasonably detailed description. ... This article refers to the plant. ... The Cronquist system is a scheme for the classification of flowering plants (or angiosperms). ... The Angiosperm Phylogeny Group is an international group of systematic botanists who have come together to try to establish a consensus view of the taxonomy of flowering plants in the light of the rapid rise of molecular systematics. ... Source: Botanical Journal of the Linnean Society Volume 141 Issue 4 Page 399 - April 2003 doi:10. ...

Traditionally, the flowering plants are divided into the dicotyledons and monocotyledons (called dicots and monocots for short). This is based mainly on the number of cotyledons or embryonic leaves within the seeds, but there are a number of other differences. These groups are typically ranked as classes, formerly called Dicotyledoneae and Monocotyledoneae, but now respectively named Class Magnoliopsida and Class Liliopsida after the type genus in each case. Orders see text Dicotyledons or dicots are flowering plants whose seed contains two embryonic leaves or cotyledons. ... Orders Base Monocots: Acorus Alismatales Asparagales Dioscoreales Liliales Pandanales Family Petrosaviaceae Commelinids: Arecales Commelinales Poales Zingiberales Family Dasypogonaceae Monocotyledons or monocots are a group of flowering plants usually ranked as a class and once called the Monocotyledoneae. ... For the genus of Crassulaceae, see Cotyledon. ...

Studies show that the monocots are monophyletic, and the dicots are paraphyletic to them. However, the majority belong to a monophyletic subgroup called the eudicotyledons or tricolpates, distinguished most notably by the form of the pollen. Since newer systems tend to avoid paraphyletic groups, these may be treated as a separate Class Rosopsida, or split into several different classes. The Magnoliopsida would then be restricted to the basal dicots or palaeodicotyledons, a paraphyletic group which may also be further divided. In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ... Paraphyletic - Wikipedia /**/ @import /skins-1. ... Orders Basal eudicots Ranunculales Buxales Trochodendrales Proteales Gunnerales Berberidopsidales Dilleniales Caryophyllales Saxifragales Santalales Vitales Basal rosids Crossosomatales Geraniales Myrtales Eurosids I Zygophyllales Celastrales Malpighiales Oxalidales Fabales Rosales Cucurbitales Fagales Eurosids II Brassicales Malvales Sapindales Basal asterids Cornales Ericales Euasterids I Garryales Solanales Gentianales Lamiales Unplaced: Boraginaceae Euasterids II Aquifoliales Apiales... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomea purpurea),hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose(Oenothera fruticosa), and castor bean (Ricinus communis). ... Orders Amborellales Nymphaeales Austrobaileyales Chloranthales Magnoliids Magnoliales Laurales Piperales (incl. ...

The most diverse families of flowering plants, in order of number of species, are:

Bumblebee pollinating an Asteraceae flower

1. Asteraceae (Daisy family): 26,000 species
2. Orchidaceae (Orchid family): 20,000 (possibly 30,000)
3. Fabaceae (Pea family): 17,000
4. Poaceae (Grass family): 9,000
5. Rubiaceae (Madder family): 7,000
6. Euphorbiaceae (Spurge family): 5,000
7. Malvaceae (Mallow family): 4,300
8. Cyperaceae (Sedge family): 4,000

In the list above (showing only the 8 largest families), the Orchidaceae, Poaceae, and Cyperaceae are monocot families; the others are dicot families. The total number of families in the Magnoliophyta is over 460. This was taken from from openphoto. ... This was taken from from openphoto. ... Species see text A bumblebee in flight The bumblebee is a flying insect of the genus Bombus in the family Apidae. ... Genera many, see list The aster or sunflower family (Family Asteraceae or, alternatively Family Compositae) is a taxon of dicotyledonous flowering plants. ... Genera many, see list The aster or sunflower family (Family Asteraceae or, alternatively Family Compositae) is a taxon of dicotyledonous flowering plants. ... Binomial name Bellis perennis L. The English daisy (Bellis perennis) is a wild flower with short creeping rhizomes and small rounded or spoon shaped evergreen leaves. ... Genera Over 800 See List of Orchidaceae genera. ... Orchid re-directs here; for alternate uses see Orchid (disambiguation) Genera Over 800 See List of Orchidaceae genera. ... Subfamilies Faboideae Caesalpinioideae Mimosoideae References GRIN-CA 2002-09-01 The Family Fabaceae (also as Family Leguminosae) is a grouping of plants in the Order Fabales, and one of the largest families of flowering plants with 650 genera and over 18,000 species. ... Binomial name Pisum sativum A pea is the small, edible round green bean which grows in a pod on the leguminous vine Pisum sativum. ... Genera See: List of Poaceae genera The true grasses are monocot (class Liliopsida) plants of the family Poaceae (formerly Graminae). ... Genera See text The Rubiaceae are a family of dicotyledon plants, variously called the madder, bedstraw, or coffee family. ... Species See text. ... Genera See text Ref: Euphorbiaceae in The Families of Flowering Plants, as of 2002-07-13 The Spurge family (Euphorbiaceae) is a large family of flowering plants with 280 genera and around 6000 species. ... This article needs cleanup. ... Genera Abelmoschus - Okra Abutilon - Abutilon Adansonia – Baobab Alcea - Hollyhock Althaea - Marsh mallow Bombax – Silk-cotton tree Callirhoe - Poppy mallow Ceiba – Kapok Chiranthodendron – Mexican Hand Tree Cola - Kola nut Corchorus - Jute Durio – Durian Fremontodendron – Flannelbush Gaya – Gaya Gossypium - Cotton plant Hibiscus - Hibiscus Hoheria – Lacebark Kosteletzkya - Saltmarsh mallow Lavatera - Tree mallow or... Mallow is the common name of several closely related genera of plant in the family Malvaceae: Malva (Mallow) Althaea (Marsh mallow) Callirhoe (Poppy mallow) Kosteletzkya (Seashore mallow) Lavatera (Tree mallow or rose mallow) Malvaviscus - Turks cap mallow Sidalcea (Greek mallow) Sphaeralcea - Globemallow Plants of the genus Malva are herbaceous... Genera See text The family Cyperaceae, or the Sedge family, is a taxon of monocot flowering plants that superficially resemble grasses or rushes. ...

Internal structure

In internal structure the variety of tissue-formation far exceeds that found in Gymnosperms (see Plant). The vascular bundles of the stem belong to the collateral type, that is to say, the elements of the wood or xylem and the bast or phloem stand side by side on the same radius. In the larger of the two great groups into which the Angiosperms are divided, the Dicotyledons, 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 tissue, known as cambium; by the formation of a layer of cambium between the bundles (interfascicular cambium) a complete ring is formed, and a regular periodical increase in thickness results from it by the development of xylem on the inside and phloem on the outside. The soft phloem soon becomes crushed, but the hard wood persists, and forms the great bulk of the stem and branches of the woody perennial. Owing to differences in the character of the elements produced at the beginning and end of the season, the wood is marked out in transverse section into concentric rings, one for each season of growth—the so-called annual rings. In the smaller group, the Monocotyledons, the bundles are more numerous in the young stem and scattered through the ground tissue. Moreover they contain no cambium and the stem once formed increases in diameter only in exceptional cases. Divisions Green algae Land plants (embryophytes) Non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants...

Vegetative organs

As in Gymnosperms, branching is monopodial; dichotomy or the forking of the growing point into two equivalent branches which replace the main stem, is absent both in the case of the stem and the root. The leaves show a remarkable variety in form, but are generally small in comparison with the size of the plant; exceptions occur in some Monocotyledons, e.g. in the Aroid family, where in some genera the plant produces one huge, much-branched leaf each season. In botany, a leaf is an above-ground plant organ specialized for photosynthesis. ...

In rare cases the main axis is unbranched and ends in a flower, as, for instance, in the tulip, where scale-leaves, forming the underground bulb, green foliage-leaves and coloured floral leaves are borne on one and the same axis. Generally, flowers are formed only on shoots of a higher order, often only on the ultimate branches of a much branched system. A potential branch or bud, either foliage or flower, is formed in the axil of each leaf; sometimes more than one bud arises, as for instance in the walnut, where two or three stand in vertical series above each leaf. Many of the buds remain dormant, or are called to development under exceptional circumstances, such as the destruction of existing branches. For instance, the clipping of a hedge or the lopping of a tree will cause to develop numerous buds which may have been dormant for years. Leaf-buds occasionally arise from the roots, when they are called adventitious; this occurs in many fruit trees, poplars, elms and others. For instance, the young shoots seen springing from the ground around an elm are not seedlings but root-shoots. Frequently, as in many Dicotyledons, the primary root, the original root of the seedling, persists throughout the life of the plant, forming, as often in biennials, a thickened tap-root, as in carrot, or in perennials, a much-branched root system. In many Dicotyledons and most Monocotyledons, the primary root soon perishes, and its place is taken by adventitious roots developed from the stem. This article is about woody plants of the genus Populus. ... Species See text Elms are deciduous trees of the genus Ulmus, family Ulmaceae. ...

The flower, fruit, and seed

• See main article: Flower

The most characteristic feature of an angiosperm is the flower, which shows remarkable variation in form and elaboration, and provides the most trustworthy external characteristics for establishing relationships among angiosperm species. The function of the flower is that of ensuring fertilization of the egg and development of fruit containing seed. The floral apparatus may arise terminally on a shoot or from the axil of a leaf. Occasionally, as in violet, a flower arises singly in the axil of an ordinary foliage-leaf. However, more typically, the flower-bearing portion of the plant is sharply distinguished from the foliage-bearing or vegetative portion, and forms a more or less elaborate branch-system called an inflorescence. Wildflowers A flower is the reproductive organ of those plants classified as angiosperms (flowering plants; Division Magnoliophyta). ... Fruit stall in Barcelona, Spain. ... A SeeD is a term given to mercenaries trained and employed by Balamb Garden in the Final Fantasy VIII video game. ... An inflorescence is a group or cluster of flowers on a branch of a plant. ...

As in gymnosperms, spores produced by flowers are of two kinds: microspores or pollen-grains, borne in the stamens (or microsporophylls) and megaspores, in which the egg-cell is developed, contained in the ovule and enclosed in the carpel (or megasporophyll). The flower may consist only of these spore-bearing parts, as in willow, where each flower comprises only a few stamens or two carpels. Usually, however, other structures are present and serve both to protect the sporophylls and to form an attractive envelope. The individual members of these surrounding structures are called sepals and petals (or tepals in a flower such as Michelia). The outer series (calyx of sepals) is usually green and leaf-like, and functions to protect the rest of the flower, especially in the bud. The inner series (corolla of petals) is generally white or brightly coloured, and more delicate in structure, and functions in attracting a particular insect or bird by agency of which pollination is effected. This attraction involves colour and scent, and frequently also nectar which is secreted in some part of the flower. These characteristics that attract pollinators account for the popularity of flowers and flowering plants among humans. The term spore has several different meanings in biology. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomea purpurea),hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose(Oenothera fruticosa), and castor bean (Ricinus communis). ... Flower of the spider tree (Crateva religiosa) with its numerous conspicuous stamens The stamen is the male organ of a flower. ... Structure found in seed plants that develops into a seed after fertilization. ... A carpel is the female reproductive organ of a flower; the basic unit of the gynoecium. ... Species About 350, including: Salix alba - White Willow Salix amygdaloides - Peachleaf Willow Salix arbuscula - Mountain Willow Salix aurita - Eared Willow Salix babylonica - Peking Willow Salix caprea - Goat Willow Salix caroliniana - Coastal Plain Willow Salix cinerea - Grey Sallow Salix fragilis - Crack Willow Salix herbacea - Dwarf Willow Salix lanata - Woolly Willow Salix... Flower of the Primrose Willowherb (Ludwigia octovalvis) showing petals and sepals A sepal is one member or part of the calyx of a flower. ... For the petals of chakras, see Petal (chakra). ...

Flowering plant sexuality

• See main article: Plant sexuality

Flowers are the reproductive organs of flowering plants. The "male" part is the stamen or androecium, which produces pollen (male gametes) in the anthers. The "female" organ is the carpel or gynoecium, which contains the egg (female gamete) and is the site of fertilization. While the majority of flowers are perfect or hermaphrodite (having both male and female parts in the same flower structure), flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization. Heteromorphic flowers have short carpels and long stamens, or vice versa, so animal pollinators cannot easily transfer pollen to the pistil (receptive part of the carpel). Homomorphic flowers may employ a biochemical (physiological) mechanism called self-incompatibility to discriminate between self- and non-self pollen grains. In other species, the male and female parts are morphologically separated, developing on different flowers. Plant sexuality deals with the wide variety of sexual reproduction systems found across the plant kingdom. ... Flower of the spider tree (Crateva religiosa) with its numerous conspicuous stamens The stamen is the male organ of a flower. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomea purpurea),hollyhock (Sildalcea malviflora), lily (Lilium auratum), primrose(Oenothera fruticosa), and castor bean (Ricinus communis). ... Gametes (in Greek: γαμέτες) —also known as sex cells, germ cells, or spores—are the specialized cells that come together during fertilization (conception) in organisms that reproduce sexually. ... A carpel is the female reproductive organ of a flower; the basic unit of the gynoecium. ... Gametes (in Greek: γαμέτες) —also known as sex cells, germ cells, or spores—are the specialized cells that come together during fertilization (conception) in organisms that reproduce sexually. ... Categories: Biology stubs ... The 1st-century BC sculpture The Reclining Hermaphrodite, in the Museo Palasso Massimo Alle Terme in Rome In zoology, a hermaphrodite is a species that contains both male and female sexual organs at some point during their lives. ... A pollinator is the agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain. ... Pin flower of English primrose Thrum flower of English primrose Self-incompatibility is one strategy that evolved with the flowering plants to maintain genetic diversity in a species population and avoid inbreeding. ...

Fertilization

At the period of fertilization the embryo-sac lies in close proximity to the opening of the micropyle, into which the pollen-tube has penetrated, the separating cell-wall becomes absorbed, and the male or sperm-cells are ejected into the embryo-sac. Guided by the synergidae one male-cell passes into the oosphere with which it fuses, the two nuclei uniting, while the other fuses with the definitive nucleus, or, as it is also called, the endosperm nucleus. This remarkable double fertilization as it has been called, although only recently discovered, has been proved to take place in widely-separated families, and both in Monocotyledons and of a prothallium after a pause following the reinvigorating union of the polar nuclei. This view is still maintained by those who differentiate two acts of fertilization within the embryo-sac, and regard that of the egg by the first male-cell, as the true or generative fertilization, and that of the polar nuclei by the second male gamete as a vegetative fertilization which gives a stimulus to development in correlation with the other. If, on the other hand, the endosperm is the product of an act of fertilization as definite as that giving rise to the embryo itself, we have to recognize that twin-plants are produced within the embryo-sac—one, the embryo, which becomes the angiospermous plant, the other, the endosperm, a short-lived, undifferentiated nurse to assist in the nutrition of the former, even as the subsidiary embryos in a pluri-embryonic Gymnosperm may facilitate the nutrition of the dominant one. If this is so, and the endosperm like the embryo is normally the product of a sexual act, hybridization will give a hybrid endosperm as it does a hybrid embryo, and herein (it is suggested) we may have the explanation of the phenomenon of xenia observed in the mixed endosperms of hybrid races of maize and other plants, regarding which it has only been possible hitherto to assert that they were indications of the extension of the influence of the pollen beyond the egg and its product. This would not, however, explain the formation of fruits intermediate in size and colour between those of crossed parents. The signification of the coalescence of the polar nuclei is not explained by these new facts, but it is noteworthy that the second male-cell is said to unite sometimes with the apical polar nucleus, the sister of the egg, before the union of this with the basal polar one.

The idea of the endosperm as a second subsidiary plant is no new one; it was suggested long ago in explanation of the coalescence of the polar nuclei, but it was then based on the assumption that these represented male and female cells, an assumption for which there was no evidence and which was inherently improbable. The proof of a coalescence of the second male nucleus with the definitive nucleus gives the conception a more stable basis. The antipodal cells aid more or less in the process of nutrition of the developing embryo, and may undergo multiplication, though they ultimately disintegrate, as do also the synergidae. As in Gymnosperms and other groups an interesting qualitative change is associated with the process of fertilization. The number of chromosomes (see Plant cytology) in the nucleus of the two spores, pollen-grain and embryo-sac, is only half the number found in an ordinary vegetative nucleus; and this reduced number persists in the cells derived from them. The full number is restored in the fusion of the male and female nuclei in the process of fertilization, and remains until the formation of the cells from which the spores are derived in the new generation.

In several natural orders and genera departures from the course of development just described have been noted. In the natural Order Rosaceae, the Series Querciflorae, and the very anomalous Genus Casuarina and others, instead of a single macrospore a more or less extensive sporogenous tissue is formed, but only one cell proceeds to the formation of a functional female cell. In Casuarina, Juglans and the Order Corylaceae, the pollen-tube does not enter by means of the micropyle, but passing down the ovary wall and through the placenta, enters at the chalazal end of the ovule. Such a method of entrance is styled chalazogamic, in contrast to the porogamic or ordinary method of approach by means of the micropyle.

Embryology

The result of fertilization is the development of the ovule into the seed. By the segmentation of the fertilized egg, now invested by cell-membrane, the embryo-plant arises. A varying number of transverse segment-walls transform it into a pro-embryo—a cellular row of which the cell nearest the micropyle becomes attached to the apex of the embryo-sac, and thus fixes the position of the developing embryo, while the terminal cell is projected into its cavity. In Dicotyledons the shoot of the embryo is wholly derived from the terminal cell of the pro-embryo, from the next cell the root arises, and the remaining ones form the suspensor. In many Monocotyledons the terminal cell forms the cotyledonary portion alone of the shoot of the embryo, its axial part and the root being derived from the adjacent cell; the cotyledon is thus a terminal structure and the apex of the primary stem a lateral one—a condition in marked contrast with that of the Dicotyledons. In some Monocotyledons, however, the cotyledon is not really terminal. The primary root of the embryo in all Angiosperms points towards the micropyle. The developing embryo at the end of the suspensor grows out to a varying extent into the forming endosperm, from which by surface absorption it derives good material for growth; at the same time the suspensor plays a direct part as a carrier of nutrition, and may even develop, where perhaps no endosperm is formed, special absorptive "suspensor roots" which invest the developing embryo, or pass out into the body and coats of the ovule, or even into the placenta. In some cases the embryo or the embryo-sac sends out suckers into the nucellus and ovular integument. As the embryo develops it may absorb all the food material available, and store, either in its cotyledons or in its hypocotyl, what is not immediately required for growth, as reserve-food for use in germination, and by so doing it increases in size until it may fill entirely the embryo-sac; or its absorptive power at this stage may be limited to what is necessary for growth and it remains of relatively small size, occupying but a small area of the embryo-sac, which is otherwise filled with endosperm in which the reserve-food is stored. There are also intermediate states. The position of the embryo in relation to the endosperm varies, sometimes it is internal, sometimes external, but the significance of this has not yet been established.

The formation of endosperm starts, as has been stated, from the endosperm nucleus. Its segmentation always begins before that of the egg, and thus there is timely preparation for the nursing of the young embryo. If in its extension to contain the new formations within it the embryo-sac remains narrow, endosperm formation proceeds upon the lines of a cell-division, but in wide embryo-sacs the endosperm is first of all formed as a layer of naked cells around the wall of the sac, and only gradually acquires a pluricellular character, forming a tissue filling the sac. The function of the endosperm is primarily that of nourishing the embryo, and its basal position in the embryo-sac places it favourably for the absorption of food material entering the ovule. Its duration varies with the precocity of the embryo. It may be wholly absorbed by the progressive growth of the embryo within the embryo-sac, or it may persist as a definite and more or less conspicuous constituent of the seed. When it persists as a massive element of the seed its nutritive function is usually apparent, for there is accumulated within its cells reserve-food, and according to the dominant substance it is starchy, oily, or rich in cellulose, mucilage or proteid. In cases where the embryo has stored reserve food within itself and thus provided for self-nutrition, such endosperm as remains in the seed may take on other functions, for instance, that of water-absorption.

Some deviations from the usual course of development may be noted. Parthenogenesis, or the development of an embryo from an egg-cell without the latter having been fertilized, has been described in species of Thalictrum, Antennaria and Alchemilla. Polyembryony is generally associated with the development of cells other than the egg-cell. Thus in Erythronium and Limnocharis the fertilized egg may form a mass of tissue on which several embryos are produced. Isolated cases show that any of the cells within the embryo-sac may exceptionally form an embryo, e.g. the synergidae in species of Mimosa, Iris and Allium, and in the last-mentioned the antipodal cells also. In Coelebogyne (Euphorbiaceae) and in Funkia (Liliaceae) polyembryony results from an adventitious production of embryos from the cells of the nucellus around the top of the embryo-sac. In a species of Allium, embryos have been found developing in the same individual from the egg-cell, synergids, antipodal cells and cells of the nucellus. In two Malayan species of Balanophora, the embryo is developed from a cell of the endosperm, which is formed from the upper polar nucleus only, the egg apparatus becoming disorganized. The last-mentioned case has been regarded as representing an apogamous development of the sporophyte from the gametophyte comparable to the cases of apogamy described in Ferns. But the great diversity of these abnormal cases as shown in the examples cited above suggests the use of great caution in formulating definite morphological theories upon them. Kaguya is one success from 460 attempts at growing embryos. ...

Fruit and seed

As the development of embryo and endosperm proceeds within the embryo-sac, its wall enlarges and commonly absorbs the substance of the nucellus (which is likewise enlarging) to near its outer limit, and combines with it and the integument to form the seed-coat; or the whole nucellus and even the integument may be absorbed. In some plants the nucellus is not thus absorbed, but itself becomes a seat of deposit of reserve-food constituting the perisperm which may coexist with endosperm, as in the water-lily order, or may alone form a food-reserve for the embryo, as in Canna. Endospermic food-reserve has evident advantages over perispermic, and the latter is comparatively rarely found and only in non-progressive series. Seeds in which endosperm or perisperm or both exist are commonly called albuminous or endospermic, those in which neither is found are termed exalbuminous or exendospermic. These terms, extensively used by systematists, only refer, however, to the grosser features of the seed, and indicate the more or less evident occurrence of a food-reserve; many so-called exalbuminous seeds show to microscopic examination a distinct endosperm which may have other than a nutritive function. The presence or absence of endosperm, its relative amount when present, and the position of the embryo within it, are valuable characters for the distinction of orders and groups of orders. Meanwhile the ovary wall has developed to form the fruit or pericarp, the structure of which is closely associated with the manner of distribution of the seed. Frequently the influence of fertilization is felt beyond the ovary, and other parts of the flower take part in the formation of the fruit, as the floral receptacle in the apple, strawberry and others. The character of the seed-coat bears a definite relation to that of the fruit. Their function is the twofold one of protecting the embryo and of aiding in dissemination; they may also directly promote germination. If the fruit is a dehiscent one and the seed is therefore soon exposed, the seed-coat has to provide for the protection of the embryo and may also have to secure dissemination. On the other hand, indehiscent fruits discharge these functions for the embryo, and the seed-coat is only slightly developed. Endosperm is a triploid tissue (containing three sets of chromosomes) found in the seeds of flowering plants. ...

Economic importance

Flowering plants provide a very high percentage of the base food for human use, whether directly or through livestock feed. Of all the families of flowering plants, the Poaceae, or grass family, is by far the most important, providing the bulk of all feedstocks (rice, corn (maize), wheat, barley, rye, oats, millet, sugar cane, sorghum), with the Fabaceae, or legume family, in second place. Also of high importance are the Solanaceae, or nightshade family (potatoes, tomatoes, and peppers, among others), the Cucurbitaceae, or gourd family (also including pumpkins and melons), the Brassicaceae, or mustard family (including rapeseed and cabbage), and the Apiaceae, or parsley family. Many of our fruits come from the Rutaceae, or rue family, and the Rosaceae (rose family, including apples, pears, cherries, apricots, plums, etc). Genera See: List of Poaceae genera The true grasses are monocot (class Liliopsida) plants of the family Poaceae (formerly Graminae). ... Species References ITIS 41975 2002-09-22 This article is about the food grain, not the university or Condoleezza Rice; see also rice (disambiguation). ... Species Zea diploperennis Zea luxurians Zea nicaraguensis Zea perennis References ITIS 42268 2002-09-22 Sorting Zea names This article is about the staple food. ... Species T. boeoticum T. durum T. monococcum T. spelta References:   ITIS 42236 2002-09-22 Wheat (Triticum spp. ... Binomial name Hordeum vulgare L. Barley (Hordeum vulgare) is a major food and animal feed crop, a member of the grass family Poaceae. ... Binomial name Secale cereale References: ITIS 42089 2002-09-22 Rye (Secale cereale) is a grass grown extensively as a grain and forage crop. ... Species References ITIS 41455 2002-09-22 Oats are the seeds of any of several cereal grains in the genus Avena. ... Nutrition information for one cup of cooked millet Millet is the collective name of a group of genera of the grass family(Gramineae/Paniceae) widely grown around the world for food or animal feed. ... Species Ref: ITIS 42058 as of 2004-05-05 Sugarcane is one of six species of a tall tropical southeast Asian grass (Family Poaceae) having stout fibrous jointed stalks whose sap at one time was the primary source of sugar. ... Species Sorghum × almum Sorghum almum Sorghum bicolor Sorghum caudatum Sorghum × drummondii Sorghum halepense Sorghum propinquum References ITIS 42106 2002-09-22 Sorghum (Sorghum vulgare or Sorghum bicolor) is a grass (Family Poaceae), the grain of which is used for food, fodder, and the production of alcoholic beverages. ... Subfamilies Faboideae Caesalpinioideae Mimosoideae References GRIN-CA 2002-09-01 The Family Fabaceae (also as Family Leguminosae) is a grouping of plants in the Order Fabales, and one of the largest families of flowering plants with 650 genera and over 18,000 species. ... Genera Acnistus Atropa (deadly nightshade) Brugmansia (angels trumpet) Calibrachoa Capsicum (chilli peppers) Datura (jimsonweed) Hyoscyamus (henbane) Iochroma Lycium (boxthorn) Lycopersicon (tomato) Mandragora (mandrake) Nicandra Nicotiana (tobacco) Petunia Physalis (tomatillo) Solandra Solanum (potato, eggplant) Streptosolen Families of Flowering Plants as of 2002-07-08 Wikispecies has information on: Solanaceae The... Binomial name Solanum tuberosum L. The potato (Solanum tuberosum) is a perennial plant of the Solanaceae, or nightshade, family, grown for its starchy tuber. ... Binomial name Solanum lycopersicum L. The tomato (Solanum lycopersicum) is a plant in the Solanaceae or nightshade family, native to South and Central America. ... Look up Pepper in Wiktionary, the free dictionary Charleston Hot peppers in varying stages of maturity. ... Genera Abobra Acanthosicyos Actinostemma Alsomitra Ampelosycios Anacaona Apatzingania Apodanthera Bambekea Benincasa Biswarea Bolbostemma Brandegea Bryonia Calycophysum Cayaponia Cephalopentandra Ceratosanthes Chalema Cionosicyos Citrullus Coccinia Cogniauxia Corallocarpus Cremastopus Ctenolepis Cucumella Cucumeropsis Cucumis Cucurbita Cucurbitella Cyclanthera Dactyliandra Dendrosicyos Dicoelospermum Dieterlea Diplocyclos Doyerea Ecballium Echinocystis Echinopepon Edgaria Elateriopsis Eureiandra Fevillea Gerrardanthus Gomphogyne Gurania Guraniopsis... A gourd is a hollow, dried shell of a fruit in the Cucurbitaceae family of plants. ... Pumpkins A pumpkin is a gourd (Cucurbitaceae), most commonly orange in colour when ripe, that grows from a trailing vine. ... Binomial name Cucumis melo L. The melon is the fruit and plant of a typically vine-like (climber and trailer) herb that was first cultivated more than 4000 years ago (~ 2000 BC) in Persia and Africa. ... Genera See text The flowering plant family Brassicaceae, known as the mustard/cabbage family, provides much of the worlds winter vegetables. ... Species See text For the Multi Unit Space Transport And Recovery Device, see the MUSTARD article. ... Binomial name Brassica napus L. Rapeseed Brassica napus, also known as Rape, Oilseed Rape, Rapa, Rapaseed and (one particular cultivar) Canola, is a bright yellow flowering member of the family Brassicaceae. ... Cultivar Group Brassica oleracea Capitata Group The cabbage (Brassica oleracea Capitata Group) is an edible plant of the Family Brassicaceae (or Cruciferae). ... Genera See text Ref: Hortiplex 2003-11-14 The Apiaceae, the carrot or parsley family, are a family of usually aromatic plants with hollow stems, including parsley, carrot, and other relatives. ... Species Parsley (Petroselinum crispum) is a bright green, biennial herb that is very common in Middle Eastern, European, and American cooking. ... Genera About 160 genera; selected important genera: Amyris - West Indian Sandalwood Choisya - Mexican orange Citrus - Citrus Dictamnus - Burning-bush Fortunella - Kumquat Melicope - Corkwood, Alani Murraya - Curry tree Phellodendron - Cork-trees Poncirus - Trifoliate orange Ptelea - Hoptree Ruta - Rue Skimmia - Skimmia Tetradium (Euodia) - Euodias Zanthoxylum - Toothache trees Rutaceae is a family of... Subfamilies Rosoideae Spiraeoideae Maloideae Amygdaloideae or Prunoideae The Rosaceae or rose family is a large family of plants, with about 3,000-4,000 species in 100-120 genera. ... Species Malus domestica Malus sieversii The apple is a tree and its pomaceous fruit, of species Malus domestica in the family Rosaceae, and is one of the most widely cultivated tree fruits. ... Species Pyrus calleryana P. pyrifolia et al Pears are trees of the genus Pyrus and the edible fruit of that tree. ... Washington, D.C. Tidal Basin showing cherry trees in flower Cherry tree blossoms A cherry is both a tree and its fleshy fruit, a type known as a drupe with a single hard pit enclosing the seed. ... Binomial name Prunus armeniaca The scientific name for the apricot is Prunus armeniaca L., which puts it in the same subgenus as the plum (Prunophora). ... Plum is also a nickname for British humorist P. G. Wodehouse. ...

In some parts of the world, certain single species assume paramount importance because of their variety of uses. An example is the coconut (Cocos nucifera) on Pacific atolls. Another example is the olive (Olea europaea) in the Mediterranean. Binomial name Cocos nucifera L. Also a song by Harry Nilsson The Coconut Palm (Cocos nucifera), is a member of the Family Arecaceae (palm family). ... Fanning Atoll (Tabuaeran) is a typical, small to moderate-sized atoll located in the central Pacific Ocean. ... Species About 20, including: Olea brachiata Olea capensis Olea caudatilimba Olea europaea Olea exasperata Olea guangxiensis Olea hainanensis Olea laxiflora Olea neriifolia Olea paniculata Olea parvilimba Olea rosea Olea salicifolia Olea tetragonoclada Olea tsoongii Olea undulata The olives (Olea) are a genus of about 20 species of small trees in... The Mediterranean Sea is an intercontinental sea positioned between Europe to the north, Africa to the south and Asia to the east, covering an approximate area of 2. ...

Flowering plants also provide economic resources in the form of wood, paper, fiber (cotton, flax, and hemp, among others), medicines (digitalis, camphor), decorative and landscaping plants, and many, many other uses. A news/talk radio station on the frequency of 1300 AM in Grand Rapids, Michigan. ... Piece of paper Paper is a thin, flat material produced by the compression of fibres. ... Cotton is a soft fiber that grows around the seeds of the cotton plant, a shrub native to the tropical and subtropical regions of both the Old World and the New World. ... Binomial name Linum usitatissimum L. Linnaeus, 17?? Common flax (also known as linseed) is a member of the Linaceae family, which includes about 150 plant species widely distributed around the world. ... U.S. Marihuana production permit, from the film Hemp for Victory. ... Species Digitalis ferruginea Digitalis grandiflora Digitalis lanata Digitalis lutea Digitalis obscura Digitalis purpurea Digitalis is a genus of about 20 species of herbaceous biennials, perennials and shrubs in the foxglove family Scrophulariaceae. ... Camphor, also known as 1,7,7-trimethyl-bicyclo(2,2,1)heptan-2-one, d-camphor, d-(+)-camphor, (+)-2-bornanone, d-2-bornanone, 1,7,7-Trimethylnorcamphor, 2-Camphanone, 2-camphonone, Bornan-2-one, or Caladryl has the chemical formula C10H16O. Camphor is a white transparent waxy crystalline solid...

See also

• List of flowers

This article or section should be merged with List of garden plants The flowers produced by flowering plants (Division Magnoliophyta) are of great interest to gardeners, florists, botanists, and nature lovers the world over. ...

References and external links

Wikibooks has a Dichotomous Key related to this taxon:

Magnoliophyta

• Angiosperm Phylogeny Group (2003). An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnean Society 141: 399-436. Available online.
• Angiosperms – Tree of Life Web Project
• Cronquist, Arthur. (1981) An Integrated System of Classification of Flowering Plants. Columbia Univ. Press, New York.
• Oldest Known Flowering Plants Identified By Genes, William J. Cromie, Harvard Gazette, December 16, 1999.
• Stevens, P.F. (2001 onwards). Angiosperm Phylogeny Website at Missouri Botanical Garden.
• L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants: descriptions, illustrations, identification, information retrieval. http://delta-intkey.com

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