1.
Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
2.
Plant
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Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. The term is generally limited to the green plants, which form an unranked clade Viridiplantae. This includes the plants, conifers and other gymnosperms, ferns, clubmosses, hornworts, liverworts, mosses and the green algae. Green plants have cell walls containing cellulose and obtain most of their energy from sunlight via photosynthesis by primary chloroplasts and their chloroplasts contain chlorophylls a and b, which gives them their green color. Some plants are parasitic and have lost the ability to produce amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although reproduction is also common. There are about 300–315 thousand species of plants, of which the great majority, green plants provide most of the worlds molecular oxygen and are the basis of most of Earths ecologies, especially on land. Plants that produce grains, fruits and vegetables form humankinds basic foodstuffs, Plants play many roles in culture. They are used as ornaments and, until recently and in variety, they have served as the source of most medicines. The scientific study of plants is known as botany, a branch of biology, Plants are one of the two groups into which all living things were traditionally divided, the other is animals. The division goes back at least as far as Aristotle, who distinguished between plants, which generally do not move, and animals, which often are mobile to catch their food. Much later, when Linnaeus created the basis of the system of scientific classification. Since then, it has become clear that the plant kingdom as originally defined included several unrelated groups, however, these organisms are still often considered plants, particularly in popular contexts. When the name Plantae or plant is applied to a group of organisms or taxon. The evolutionary history of plants is not yet settled. Those which have been called plants are in bold, the way in which the groups of green algae are combined and named varies considerably between authors. Algae comprise several different groups of organisms which produce energy through photosynthesis, most conspicuous among the algae are the seaweeds, multicellular algae that may roughly resemble land plants, but are classified among the brown, red and green algae. Each of these groups also includes various microscopic and single-celled organisms
3.
Flowering plant
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The flowering plants, also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 416 families, approx. 13,164 known genera and a total of c.295,383 known species, etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term angiosperm comes from the Greek composite word meaning enclosed seeds, the ancestors of flowering plants diverged from gymnosperms in the Triassic Period, during the range 245 to 202 million years ago, and the first flowering plants are known from 160 mya. They diversified extensively during the Lower Cretaceous, became widespread by 120 mya, angiosperms differ from other seed plants in several ways, described in the table. These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants, the amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms. The vascular bundles of the stem are arranged such that the xylem and phloem form concentric rings, in 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, the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Among the monocotyledons, the bundles are more numerous in the stem and are scattered through the ground tissue. They contain no cambium and once formed the stem increases in diameter only in exceptional cases, 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, occasionally, as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. There are two kinds of cells produced by flowers. Microspores, which divide to become pollen grains, are the male cells and are borne in the stamens. The female cells called megaspores, which divide to become the egg cell, are contained in the ovule. The flower may consist only of parts, as in willow. Usually, other structures are present and serve to protect the sporophylls, the individual members of these surrounding structures are known as sepals and petals. The outer series is usually green and leaf-like, and functions to protect the rest of the flower, the inner series is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators, attraction is effected by color, scent, and nectar, which may be secreted in some part of the flower
4.
Monocotyledon
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Monocotyledons, commonly referred to as monocots, are flowering plants whose seeds typically contain only one embryonic leaf, or cotyledon. However, molecular research has shown that while the monocots form a monophyletic group or clade. Monocots have almost always recognized as a group, but with various taxonomic ranks. The APG III system of 2009 recognises a clade called monocots, the monocots include about 60,000 species. The largest family in this group by number of species are the orchids, about half as many species belong to the true grasses, which are economically the most important family of monocots. In agriculture the majority of the biomass produced comes from monocots and these include not only major grains, but also forage grasses, sugar cane, and the bamboos. Other economically important monocot crops include various palms, bananas, gingers and their relatives, turmeric and cardamom, asparagus and the onions and garlic family. Additionally most of the bulbs, plants cultivated for their blooms, such as lilies, daffodils, irises, amaryllis, cannas, bluebells. The monocots or monocotyledons have, as the name implies, a single cotyledon, or embryonic leaf, from a diagnostic point of view the number of cotyledons is neither a particularly useful characteristic, nor is it completely reliable. Nevertheless, monocots are sufficiently distinctive that there has rarely been disagreement as to membership of this group, however, morphological features that reliably characterise major clades are rare. Thus monocots are distinguishable from other angiosperms both in terms of their uniformity and diversity, although largely herbaceous, some arboraceous monocots reach great height, length and mass. The latter include agaves, palms, pandans, and bamboos and this creates challenges in water transport that monocots deal with in various ways. Some such as species of Yucca develop anomalous secondary growth, while palm trees, the axis undergoes primary thickening, that progresses from internode to internode, resulting in a typical inverted conical shape of the basal primary axis. The limited conductivity also contributes to limited branching of the stems, despite these limitations a wide variety of adaptive growth forms has resulted from epiphytic orchids and bromeliads to submarine Alismatales and mycotrophic Burmanniaceae and Triuridaceae. Other monocots, particularly Poales have adopted a life form. Leaves The cotyledon, the primordial Angiosperm leaf consists of a proximal leaf base or hypophyll, in moncots the hypophyll tends to be the dominant part in contrast to other angiosperms. Mature monocot leaves are narrow and linear, forming a sheathing around the stem at its base. There is usually only one leaf per node because the leaf base encompasses more than half the circumference, the evolution of this monocot characteristic has been attributed to developmental differences in early zonal differentiation rather than meristem activity
5.
Asparagales
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Asparagales is an order of plants in modern classification systems such as the Angiosperm Phylogeny Group and the Angiosperm Phylogeny Web. The order takes its name from the type family Asparagaceae and is placed in the monocots amongst the lilioid monocots, the order has only recently been recognized in classification systems. It was first put forward by Huber in 1977 and later taken up in the Dahlgren system of 1985 and then the APG in 1998,2003 and 2009. Before this, many of its families were assigned to the old order Liliales, DNA sequence analysis indicated that many of the taxa previously included in Liliales should actually be redistributed over three orders, Liliales, Asparagales and Dioscoreales. The boundaries of the Asparagales and of its families have undergone a series of changes in recent years, future research may lead to further changes and ultimately greater stability. In the APG circumscription, Asparagales is the largest order of monocots with 14 families,1,122 genera, the order is clearly circumscribed on the basis of molecular phylogenetics, but is difficult to define morphologically, since its members are structurally diverse. Most species of Asparagales are herbaceous perennials, although some are climbers, the order also contains many geophytes. According to telomere sequence, at least two evolutionary switch-points happened within the order, basal sequence is formed by TTTAGGG like in majority of higher plants. Basal motif was changed to vertebrate-like TTAGGG and finally the most divergent motif CTCGGTTATGGG appears in Allium, one of the defining characteristics of the order is the presence of phytomelanin, a black pigment present in the seed coat, creating a dark crust. Phytomelanin is found in most families of the Asparagales, the leaves of almost all species form a tight rosette, either at the base of the plant or at the end of the stem, but occasionally along the stem. The flowers are not particularly distinctive, being lily type, with six tepals, from an economic point of view, the order Asparagales is second in importance within the monocots to the order Poales. Species are used as food and flavourings, as cut flowers, and as garden ornamentals. Thus although most species in the order are herbaceous, some no more than 15 cm high, there are a number of climbers, as well as several genera forming trees, succulent genera occur in several families. Almost all species have a cluster of leaves, either at the base of the plant or at the end of a more-or-less woody stem as with Yucca. In some cases the leaves are produced along the stem, the flowers are in the main not particularly distinctive, being of a general lily type, with six tepals, either free or fused from the base and up to six stamina. They are frequently clustered at the end of the plant stem and they are generally geophytes, but with linear leaves, and a lack of fine reticular venation. The seeds characteristically have the external epidermis either obliterated, or if present, have a layer of black carbonaceous phytomelanin in species with dry fruits. The inner part of the coat is generally collapsed, in contrast to Liliales whose seeds have a well developed outer epidermis, lack phytomelanin
6.
Orchidaceae
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The Orchidaceae are a diverse and widespread family of flowering plants, with blooms that are often colourful and often fragrant, commonly known as the orchid family. Along with the Asteraceae, they are one of the two largest families of flowering plants, the Orchidaceae have about 28,000 currently accepted species, distributed in about 763 genera. The determination of which family is larger is still under debate, regardless, the number of orchid species nearly equals the number of bony fishes and is more than twice the number of bird species, and about four times the number of mammal species. The family also encompasses about 6–11% of all seed plants, the largest genera are Bulbophyllum, Epidendrum, Dendrobium and Pleurothallis. The family also includes Vanilla, Orchis, and many cultivated plants such as Phalaenopsis. Moreover, since the introduction of species into cultivation in the 19th century, horticulturists have produced more than 100,000 hybrids. Orchids are easily distinguished from plants, as they share some very evident, shared derived characteristics. Among these are, bilateral symmetry of the flower, many flowers, a nearly always highly modified petal, fused stamens and carpels. All orchids are perennial herbs that lack any permanent woody structure and they can grow according to two patterns, Monopodial, The stem grows from a single bud, leaves are added from the apex each year and the stem grows longer accordingly. The stem of orchids with a monopodial growth can reach several metres in length, as in Vanda, Sympodial, Sympodial orchids have a front and a back. The plant produces a series of adjacent shoots which grow to a size, bloom. Sympodial orchids grow laterally rather than vertically, following the surface of their support, the growth continues by development of new leads, with their own leaves and roots, sprouting from or next to those of the previous year, as in Cattleya. While a new lead is developing, the rhizome may start its growth again from a so-called eye, Sympodial orchids may have visible pseudobulbs joined by a rhizome, which creeps along the top or just beneath the soil. Terrestrial orchids may be rhizomatous or form corms or tubers, the root caps of terrestrial orchids are smooth and white. Some sympodial terrestrial orchids, such as Orchis and Ophrys, have two subterranean tuberous roots, one is used as a food reserve for wintry periods, and provides for the development of the other one, from which visible growth develops. In warm and constantly humid climates, many terrestrial orchids do not need pseudobulbs, epiphytic orchids, those that grow upon a support, have modified aerial roots that can sometimes be a few meters long. In the older parts of the roots, a modified spongy epidermis and it is made of dead cells and can have a silvery-grey, white or brown appearance. In some orchids, the velamen includes spongy and fibrous bodies near the passage cells, the cells of the root epidermis grow at a right angle to the axis of the root to allow them to get a firm grasp on their support
7.
Orchidoideae
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The Orchidoideae, or the orchidoid orchids, are a subfamily of the orchid family. They typically contain the orchids with a single, fertile anther which is erect and it is sister to the tribe Diurideae. l. BATEMAN, PETER M. HOLLINGSWORTH, JILLIAN PRESTON, LUO YI-BO, ALEC M. PRIDGEON, molecular phylogenetics and evolution of Orchidinae and selected Habenariinae. Botanical Journal of the Linnean Society, Oxford University Press, Oxford, U. K. Salazar, G. A. Chase, M. A. Soto Arenas and M. Ingrouille, phylogenetics of Cranichideae with emphasis on Spiranthinae, evidence from plastid and nuclear DNA sequences. American Journal of Botany 90, 777-795, Phylogenetic relationships of Cranichidinae and Prescottiinae inferred from plastid and nuclear DNA sequences. Chemisquy, M. A. Morrone, O. Phylogenetic analysis of the subtribe Chloraeinae, a preliminary approach based on three chloroplast markers
8.
Ophrys
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The genus Ophrys is a large group of orchids from the alliance Orchis in the subtribe Orchidinae. They are widespread across much of Europe, North Africa, the Canary Islands, and they are referred to as the bee orchids due to the flowers of some species resemblance to the furry bodies of bees and other insects. Their scientific name Ophrys is the Greek word for eyebrow, referring to the edges of the lips of several species. Ophrys was first mentioned in the book Natural History by Pliny the Elder and they are terrestrial or ground orchids from central to South Europe, North Africa, Asia Minor, up to the Caucasus Mountains, but mostly in the Mediterranean region. They have been said to be the most important group of European terrestrial orchids, during summer, all Ophrys orchids are dormant as underground bulbous tubers, which serve as a food reserve. In late summer/autumn they develop a rosette of leaves, also a new tuber starts to grow and matures until the following spring, the old tuber slowly dies. The next spring the flowering stem starts to grow, during flowering the leaves have already started to wither. Most Ophrys orchids are dependent on symbiotic fungi, transplanting specimens, especially wild specimens, is difficult, sometimes impossible, due to this symbiosis unless a large amount of surrounding earth is also taken with the plant. All orchids are protected under CITES II and should not be removed or disturbed in habitat, the shiny, basal leaves have a green or bluish color. Two to twelve flowers grow on a stem with basal leaves. Orchids of the genus Ophrys use sexual deception to attract pollinators to their flowers, in sexual deception, an orchid attracts male pollinators by producing the sex pheromone of virgin female pollinators in addition to providing visual and tactile cues. These signals stimulate mating behavior in the male pollinators, which then attempt copulation, called “pseudocopulation”, the allomone produced by an orchid is specific to its pollinator, of which it usually only has one. The allomone is a mixture of alkenes and alkanes, there are one or more active species in this mixture that account for the attraction of pollinators. Pollinators and orchids use the chemical compounds in the same absolute amounts in their pheromones and allomones. Every Ophrys orchid has its own pollinator insect and is dependent on this species for its survival. Duped males are likely to return and may ignore other plants of the same species. Only about 10% of an Ophrys population gets pollinated and this is enough to preserve the population, since each Ophrys orchid produces about 12,000 minute seeds. Almost 2000 names have been proposed for species, subspecies, the number of species recognized varies very widely between authorities
9.
Binomial nomenclature
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Such a name is called a binomial name, a binomen, binominal name or a scientific name, more informally it is also called a Latin name. The first part of the name identifies the genus to which the species belongs, for example, humans belong to the genus Homo and within this genus to the species Homo sapiens. The formal introduction of system of naming species is credited to Carl Linnaeus. But Gaspard Bauhin, in as early as 1623, had introduced in his book Pinax theatri botanici many names of genera that were adopted by Linnaeus. Although the general principles underlying binomial nomenclature are common to these two codes, there are differences, both in the terminology they use and in their precise rules. Similarly, both parts are italicized when a binomial name occurs in normal text, thus the binomial name of the annual phlox is now written as Phlox drummondii. In scientific works, the authority for a name is usually given, at least when it is first mentioned. In zoology Patella vulgata Linnaeus,1758, the original name given by Linnaeus was Fringilla domestica, the parentheses indicate that the species is now considered to belong in a different genus. The ICZN does not require that the name of the person who changed the genus be given, nor the date on which the change was made, in botany Amaranthus retroflexus L. – L. is the standard abbreviation used in botany for Linnaeus. – Linnaeus first named this bluebell species Scilla italica, Rothmaler transferred it to the genus Hyacinthoides, the ICN does not require that the dates of either publication be specified. Prior to the adoption of the binomial system of naming species. Together they formed a system of polynomial nomenclature and these names had two separate functions. First, to designate or label the species, and second, to be a diagnosis or description, such polynomial names may sometimes look like binomials, but are significantly different. For example, Gerards herbal describes various kinds of spiderwort, The first is called Phalangium ramosum, Branched Spiderwort, is aptly termed Phalangium Ephemerum Virginianum, Soon-Fading Spiderwort of Virginia. The Latin phrases are short descriptions, rather than identifying labels, the Bauhins, in particular Caspar Bauhin, took some important steps towards the binomial system, by pruning the Latin descriptions, in many cases to two words. The adoption by biologists of a system of binomial nomenclature is due to Swedish botanist and physician Carl von Linné. It was in his 1753 Species Plantarum that he first began using a one-word trivial name together with a generic name in a system of binomial nomenclature. This trivial name is what is now known as an epithet or specific name
10.
Philip Miller
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Philip Miller FRS was an English botanist of Scottish descent. Born in Deptford or Greenwich Miller was chief gardener at the Chelsea Physic Garden from 1722 until he was pressured to retire shortly before his death. Miller corresponded with botanists, and obtained plants from all over the world. His knowledge of living plants, for which he was elected a Fellow of the Royal Society, was unsurpassed in breadth in his lifetime and he trained William Aiton, who later became head gardener at Kew, and William Forsyth, after whom Forsythia was named. Through a consortium of sixty subscribers, 1733–66, the contents of Bartrams boxes introduced such American trees as Abies balsamea, Miller was reluctant to use the new binomial nomenclature of Carl Linnaeus, preferring the classifications of Joseph Pitton de Tournefort and John Ray at first. Miller sent the first long-strand cotton seeds, which he had developed and they were first planted on Sea Island, off the coast of Georgia, and hence derived the name of the finest cotton, Sea Island Cotton. The presumed portrait, engraved by C. J, millers two sons worked under him, one, Charles, became the first head of the Cambridge Botanic Garden. Miller, Philip The Gardeners Kalendar - digital facsimile from Linda Hall Library Miller, Philip Figures of the most beautiful, useful, - digital facsimile from Linda Hall Library
