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Land Plants
The embryophytes () are a clade of plants, also known as Embryophyta (Plantae ''sensu strictissimo'') () or land plants. They are the most familiar group of photoautotrophs that make up the vegetation on Earth's dry lands and wetlands. Embryophytes have a common ancestor with green algae, having emerged within the Phragmoplastophyta clade of freshwater charophyte green algae as a sister taxon of Charophyceae, Coleochaetophyceae and Zygnematophyceae. Embryophytes consist of the bryophytes and the polysporangiophytes. Living embryophytes include hornworts, liverworts, mosses, lycophytes, ferns, gymnosperms and angiosperms (flowering plants). Embryophytes have diplobiontic life cycles. The embryophytes are informally called "land plants" because they thrive primarily in terrestrial habitats (despite some members having evolved secondarily to live once again in semiaquatic/ aquatic habitats), while the related green algae are primarily aquatic. Embryophytes are comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moss
Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryophytes, which comprise Marchantiophyta, liverworts, mosses, and hornworts. Mosses typically form dense green clumps or mats, often in damp or shady locations. The individual plants are usually composed of simple leaf, leaves that are generally only one cell thick, attached to a plant stem, stem that may be branched or unbranched and has only a limited role in conducting water and nutrients. Although some species have conducting tissues, these are generally poorly developed and structurally different from similar tissue found in vascular plants. Mosses do not have seeds and after fertilisation develop sporophytes with unbranched stalks topped with single capsules containing sporangium, spores. They are typically tall, though some species ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cycad
Cycads are seed plants that typically have a stout and woody (ligneous) trunk (botany), trunk with a crown (botany), crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, that is, individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow slowly and have long lifespans. Because of their superficial resemblance to Arecaceae, palms or ferns, they are sometimes mistaken for them, but they are not closely related to either group. Cycads are gymnosperms (naked-seeded), meaning their fertilization, unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific beetle, and more rarely a thrips or a moth. Both male and female cycads bear cones (strobilus, stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lynn Margulis
Lynn Margulis (born Lynn Petra Alexander; March 5, 1938 – November 22, 2011) was an American evolutionary biologist, and was the primary modern proponent for the significance of symbiogenesis, symbiosis in evolution. In particular, Margulis transformed and fundamentally framed current understanding of the evolution of Eukaryote, cells with nuclei by proposing it to have been the result of symbiotic mergers of bacteria. Margulis was also the co-developer of the Gaia hypothesis with the British chemist James Lovelock, proposing that the Earth functions as a single self-regulating system, and was the principal defender and promulgator of the Five kingdoms, five kingdom classification of Robert Whittaker (ecologist), Robert Whittaker. Throughout her career, Margulis' work could arouse intense objections, and her formative paper, "On the Origin of Mitosing Cells", appeared in 1967 after being rejected by about fifteen journals. Still a junior faculty member at Boston University at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Cronquist
Arthur John Cronquist (March 19, 1919 – March 22, 1992) was an American biologist, botanist and a specialist on Compositae. He is considered one of the most influential botanists of the 20th century, largely due to his formulation of the Cronquist system as well as being the primary co-author to the Flora of the Pacific Northwest, still the most up to date flora for three northwest U.S. States to date. Two plant genera in the aster family have been named in his honor. These are ''Cronquistia'', a possible synonym of '' Carphochaete'', and '' Cronquistianthus'', which is sometimes included as a group within ''Eupatorium''. The former was applied by R.M. King and the latter by him and Harold E. Robinson. Life Arthur Cronquist was born on March 19, 1919, in San Jose, California, but he grew up outside of Portland, Oregon, as well as in Pocatello, Idaho. His parents divorced when he was young and he and his older sister were brought up by his mother, who worked for the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Takhtajan
Armen Leonovich Takhtajan or Takhtajian (; surname also transliterated Takhtadjan, Takhtadzhi︠a︡n or Takhtadzhian, pronounced takh-tuh-JAHN; 10 June 1910 – 13 November 2009), was a Soviet-Armenian botanist, one of the most important figures in 20th century plant evolution and systematics and biogeography. His other interests included morphology of flowering plants, paleobotany, and the flora of the Caucasus. He was one of the most influential taxonomists of the latter twentieth century. Life Family Takhtajan was born in Shushi, Russian Empire, present-day disputed Nagorno-Karabakh, on 10 June 1910, to a family of Armenian intellectuals. His grandfather Meliksan Takhtadzhyan Petrovich had been born in Trabzon, Ottoman Empire and was educated in Italy, on the island of San Lazzaro degli Armeni, an Armenian enclave, spoke many languages and worked as a journalist. He died in Paris in 1930. His father, Leon Meliksanovich Takhtadzhyan (1884–1950), was born in Batumi, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Werner Rothmaler
Werner Walter Hugo Paul Rothmaler (born 20 August 1908 in Sangerhausen, died 13 April 1962 in Leipzig) was a German botanist and from 1953 until 1962 head of the Institute for Agricultural Biology of the University of Greifswald. His areas of expertise included plant geography and systematics. Career Rothmaler's secondary schooling took place in Weimar at the Wilhelm-Ernst-Gymnasium. His wide interests ranged from botany to painting and politics. He became friendly with the family of the artist Lyonel Feininger and particularly with his son Andreas, and he was inspired by the ideas of the Bauhaus. All this brought him into conflict with the school authorities and he left the school without his abitur. Kreisel, Hanns (1999) "Wir nannten ihn Vadder". – Werner Rothmaler – ein außergewöhnlicher Hochschullehrer 1908–1962. ''Greifswalder Universitätsreden'', Neue Folge Nr. 90. Greifswald 1999, (Abdruck eines Vortrages aus Anlass des 90. Geburtstages von Werner Rothmaler) From 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fred Alexander Barkley
Fred Alexander Barkley (1908–1989) was an American botanist. Barkley studied at the University of Oklahoma The University of Oklahoma (OU) is a Public university, public research university in Norman, Oklahoma, United States. Founded in 1890, it had existed in Oklahoma Territory near Indian Territory for 17 years before the two territories became the ... and was awarded a PhD from the Washington University in St. Louis in 1937. References {{DEFAULTSORT:Barkley, Fred Alexander 1908 births 1989 deaths 20th-century American botanists University of Oklahoma alumni Washington University in St. Louis alumni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephan Endlicher
Stephan Friedrich Ladislaus Endlicher, also known as Endlicher István László (24 June 1804 – 28 March 1849), was an Austrian Empire, Austrian botanist, numismatist and Sinologist. He was a director of the Botanical Garden of Vienna. Biography Endlicher studied theology and received minor orders. In 1828 he was appointed to the Österreichische Nationalbibliothek, Austrian National Library to reorganize its manuscript collection. Concurrently he studied natural history, in particular botany, and East-Asian languages. In 1836, Endlicher was appointed keeper of the court cabinet of natural history, and in 1840 he became professor at the University of Vienna and director of its Botanical Garden of the University of Vienna, Botanical Garden. He wrote a comprehensive description of the plant kingdom according to a natural system, at the time its most comprehensive description. As proposed by Endlicher, it contained images with text. It was published together with the reissue of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiospermae
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed within a fruit. The group was formerly called Magnoliophyta. Angiosperms are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of broad-leaved trees, shrubs and vines, and most aquatic plants. Angiosperms are distinguished from the other major seed plant clade, the gymnosperms, by having flowers, xylem consisting of vessel elements instead of tracheids, endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous, ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gymnospermae
The gymnosperms ( ; ) are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term ''gymnosperm'' comes from the composite word in ( and ), and literally means 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, ''Torreya'', and ''Ginkgo''. The life cycle of a gymnosperm involves alternation of generations, with a dominant diploid sporophyte phase, and a reduced haploid gametophyte phase, which is dependent on the sporophytic phase. The term "gym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridophyta
A pteridophyte is a vascular plant (with xylem and phloem) that reproduces by means of spores. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as " cryptogams", meaning that their means of reproduction is hidden. They are also the ancestors of the plants we see today. Ferns, horsetails (often treated as ferns), and lycophytes (clubmosses, spikemosses, and quillworts) are all pteridophytes. However, they do not form a monophyletic group because ferns (and horsetails) are more closely related to seed plants than to lycophytes. "Pteridophyta" is thus no longer a widely accepted taxon, but the term ''pteridophyte'' remains in common parlance, as do ''pteridology'' and ''pteridologist'' as a science and its practitioner, for example by the International Association of Pteridologists and the Pteridophyte Phylogeny Group. Etymology The name ''Pteridophyte'' is a Neo-Latin compound word created by English speakers around 1880. It is formed f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyletic
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic grouping (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term received currency during the debates of the 1960s and 1970s accompanying the rise of cladistics, having been coined by zoologist Willi Hennig to apply to well-known taxa like Reptilia (reptiles), which is paraphyletic with respect to birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancestor exc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
