The flowering plants known as angiosperms, Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 64 orders, 416 families 13,164 known genera and c. 369,000 known species. Like gymnosperms, angiosperms are seed-producing plants. However, they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, the production of fruits that contain the seeds. Etymologically, angiosperm means a plant; the term comes from the Greek words sperma. The ancestors of flowering plants diverged from gymnosperms in the Triassic Period, 245 to 202 million years ago, the first flowering plants are known from 160 mya, they diversified extensively during the Early Cretaceous, became widespread by 120 mya, replaced conifers as the dominant trees from 100 to 60 mya. 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.
Angiosperm stems are made up of seven layers. 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 phloem form concentric rings. In the dicotyledons, the bundles in the 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, a complete ring is formed, a regular periodical increase in thickness results from the development of xylem on the inside and phloem on the outside; the soft phloem becomes crushed, but the hard wood persists and forms the 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, called annual rings.
Among the monocotyledons, the bundles are more numerous in the young stem and are scattered through the ground tissue. They 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, 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 from the axil of a leaf; as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. More the flower-bearing portion of the plant is distinguished from the foliage-bearing or vegetative portion, forms a more or less elaborate branch-system called an inflorescence. There are two kinds of reproductive cells produced by flowers. Microspores, which will divide to become pollen grains, are the "male" cells and are borne in the stamens.
The "female" cells called megaspores, which will divide to become the egg cell, are contained in the ovule and enclosed in the carpel. The flower may consist only of these parts, as in willow, where each flower comprises only a few stamens or two carpels. Other structures are present and serve to protect the sporophylls and to form an envelope attractive to pollinators; the individual members of these surrounding structures are known as petals. The outer series is green and leaf-like, functions to protect the rest of the flower the bud; the inner series is, in general, white or brightly colored, is more delicate in structure. It functions to attract bird pollinators. Attraction is effected by color and nectar, which may be secreted in some part of the flower; the characteristics that attract pollinators account for the popularity of flowers and flowering plants among humans. While the majority of flowers are perfect or hermaphrodite, 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 transfer pollen to the pistil. Homomorphic flowers may employ a biochemical 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; the botanical term "Angiosperm", from the Ancient Greek αγγείον, angeíon and σπέρμα, was coined in the form Angiospermae by Paul Hermann in 1690, as the name of one of his primary divisions of the plant kingdom. This included flowering plants possessing seeds enclosed in capsules, distinguished from 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 Carl Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any
Plants are multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. Plants were treated as one of two kingdoms including all living things that were not animals, all algae and fungi were treated as plants. However, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes. By one definition, plants form the clade Viridiplantae, a group that includes the flowering plants and other gymnosperms and their allies, liverworts and the green algae, but excludes the red and brown algae. Green plants obtain most of their energy from sunlight via photosynthesis by primary chloroplasts that are derived from endosymbiosis with cyanobacteria, their chloroplasts contain b, which gives them their green color. Some plants are parasitic or mycotrophic and have lost the ability to produce normal amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although asexual reproduction is common.
There are about 320 thousand species of plants, of which the great majority, some 260–290 thousand, are seed plants. Green plants provide a substantial proportion of the world's molecular oxygen and are the basis of most of Earth's ecosystems on land. Plants that produce grain and vegetables form humankind's basic foods, have been domesticated for millennia. Plants have many cultural and other uses, as ornaments, building materials, writing material and, in great variety, they have been the source of medicines and psychoactive drugs; the scientific study of plants is known as a branch of biology. All living things were traditionally placed into one of two groups and animals; this classification may date from Aristotle, who made the distincton between plants, which do not move, animals, which are mobile to catch their food. Much when Linnaeus created the basis of the modern system of scientific classification, these two groups became the kingdoms Vegetabilia and Animalia. Since it has become clear that the plant kingdom as defined included several unrelated groups, the fungi and several groups of algae were removed to new kingdoms.
However, these organisms are still considered plants in popular contexts. The term "plant" implies the possession of the following traits multicellularity, possession of cell walls containing cellulose and the ability to carry out photosynthesis with primary chloroplasts; when the name Plantae or plant is applied to a specific group of organisms or taxon, it refers to one of four concepts. From least to most inclusive, these four groupings are: Another way of looking at the relationships between the different groups that have been called "plants" is through a cladogram, which shows their evolutionary relationships; these are not yet settled, but one accepted relationship between the three groups described above is shown below. Those which have been called "plants" are in bold; the way in which the groups of green algae are combined and named varies between authors. Algae comprise several different groups of organisms which produce food by photosynthesis and thus have traditionally been included in the plant kingdom.
The seaweeds range from large multicellular algae to single-celled organisms and are classified into three groups, the green algae, red algae and brown algae. There is good evidence that the brown algae evolved independently from the others, from non-photosynthetic ancestors that formed endosymbiotic relationships with red algae rather than from cyanobacteria, they are no longer classified as plants as defined here; the Viridiplantae, the green plants – green algae and land plants – form a clade, a group consisting of all the descendants of a common ancestor. With a few exceptions, the green plants have the following features in common, they undergo closed mitosis without centrioles, have mitochondria with flat cristae. The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. Two additional groups, the Rhodophyta and Glaucophyta have primary chloroplasts that appear to be derived directly from endosymbiotic cyanobacteria, although they differ from Viridiplantae in the pigments which are used in photosynthesis and so are different in colour.
These groups differ from green plants in that the storage polysaccharide is floridean starch and is stored in the cytoplasm rather than in the plastids. They appear to have had a common origin with Viridiplantae and the three groups form the clade Archaeplastida, whose name implies that their chloroplasts were derived from a single ancient endosymbiotic event; this is the broadest modern definition of the term'plant'. In contrast, most other algae not only have different pigments but have chloroplasts with three or four surrounding membranes, they are not close relatives of the Archaeplastida having acquired chloroplasts separately from ingested or symbiotic green and red algae. They are thus not included in the broadest modern definition of the plant kingdom, although they were in the past; the green plants or Viridiplantae were traditionally divided into the green algae (including
Herbaceous plants are plants that have no persistent woody stem above ground. The term is applied to perennials, but in botany it may refer to annuals or biennials, include both forbs and graminoids. Annual herbaceous plants die at the end of the growing season or when they have flowered and fruited, they grow again from seed. Herbaceous perennial and biennial plants may have stems that die at the end of the growing season, but parts of the plant survive under or close to the ground from season to season. New growth develops from living tissues remaining on or under the ground, including roots, a caudex or various types of underground stems, such as bulbs, stolons and tubers. Examples of herbaceous biennials include carrot and common ragwort. By contrast, non-herbaceous perennial plants are woody plants which have stems above ground that remain alive during the dormant season and grow shoots the next year from the above-ground parts – these include trees and vines; some fast-growing herbaceous plants are pioneers, or early-successional species.
Others form the main vegetation of many stable habitats, occurring for example in the ground layer of forests, or in open habitats such as meadow, salt marsh or desert. Some herbaceous plants can grow rather large, such as the genus Musa; the age of some herbaceous perennial plants can be determined by herbchronology, the analysis of annual growth rings in the secondary root xylem
Asterales is an order of dicotyledonous flowering plants that includes the large family Asteraceae known for composite flowers made of florets, ten families related to the Asteraceae. The order is a cosmopolite, includes herbaceous species, although a small number of trees and shrubs are present. Asterales are organisms. Asterales share characteristics on biochemical levels. Synapomorphies include the presence in the plants of oligosaccharide inulin, a nutrient storage molecule used instead of starch; the stamens are found around the style, either aggregated densely or fused into a tube an adaptation in association with the plunger pollination, common among the families of the order, wherein pollen is collected and stored on the length of the pistil. The name and order Asterales is botanically venerable, dating back to at least 1926 in the Hutchinson system of plant taxonomy when it contained only five families, of which only two are retained in the APG III classification. Under the Cronquist system of taxonomic classification of flowering plants, Asteraceae was the only family in the group, but newer systems have expanded it to 11.
In the classification system of Dahlgren the Asterales were in the superorder Asteriflorae. The order Asterales includes 11 families, the largest of which are the Asteraceae, with about 25,000 species, the Campanulaceae, with about 2,000 species; the remaining families count together for less than 1500 species. The two large families are cosmopolitan, with many of their species found in the Northern Hemisphere, the smaller families are confined to Australia and the adjacent areas, or sometimes South America. Only the Asteraceae have composite flower heads; the phylogenetic tree according to APG III for the Campanulid clade is as below. The core Asterales are Stylidiaceae, APA clade, MGCA clade, Asteraceae. Other Asterales are Rousseaceae and Pentaphragmataceae. All Asterales families are represented in the Southern Hemisphere. Although most extant species of Asteraceae are herbaceous, the examination of the basal members in the family suggests that the common ancestor of the family was an arborescent plant, a tree or shrub adapted to dry conditions, radiating from South America.
Less can be said about the Asterales themselves with certainty, although since several families in Asterales contain trees, the ancestral member is most to have been a tree or shrub. Because all clades are represented in the southern hemisphere but many not in the northern hemisphere, it is natural to conjecture that there is a common southern origin to them. Asterales are angiosperms; the Asterales order originated in the Cretaceous on the supercontinent Gondwana which broke up from 184 – 80 Mya, forming the area, now Australia, South America, Africa and Antarctica. Asterales contain about 14% of eudicot diversity. From an analysis of relationships and diversities within the Asterales and with their superorders, estimates of the age of the beginning of the Asterales have been made, which range from 116 Mya to 82Mya; however few fossils have been found, of the Menyanthaceae-Asteraceae clade in the Oligocene, about 29 Mya. Fossil evidence of the Asterales is rare and belongs to rather recent epochs, so the precise estimation of the order's age is quite difficult.
An Oligocene pollen is known for Asteraceae and Goodeniaceae, seeds from Oligocene and Miocene are known for Menyanthaceae and Campanulaceae respectively. The Asterales, by dint of being a super-set of the family Asteraceae, include some species grown for food, including the sunflower and chicory. Many are used as spices and traditional medicines. Asterales have many known uses. For example, pyrethrum is a natural insecticide with minimal environmental impact. Wormwood, derived from a genus that includes the sagebrush, is used as a source of flavoring for absinthe, a bitter classical liquor of European origin. W. S. Judd, C. S. Campbell, E. A. Kellogg, P. F. Stevens, M. J. Donoghue. Plant Systematics: A Phylogenetic Approach, 2nd edition. Pp. 476–486. Sinauer Associates, Massachusetts. ISBN 0-87893-403-0. J. Lindley. Nixus Plantarum, 20. Londini. Smissen, R. D.. Asterales. In: Nature Encyclopedia of Life Sciences. Nature Publishing Group, London. "Asterales -- Britannica Online Encyclopedia." Encyclopedia - Britannica Online Encyclopedia.
Web. 19 Jan. 2012. <http://www.britannica.com/EBchecked/topic/39703/Asterales>. "Asterales - Definition and More from the Free Merriam-Webster Dictionary." Dictionary and Thesaur
"Rapunzel" is a German fairy tale in the collection assembled by the Brothers Grimm, first published in 1812 as part of Children's and Household Tales. The Grimm Brothers' story is an adaptation of the fairy tale Rapunzel by Friedrich Schulz published in 1790; the Schulz version is based on Persinette by Charlotte-Rose de Caumont de La Force published in 1698 which in turn was influenced by an earlier Italian tale, Petrosinella by Giambattista Basile, published in 1634. Its plot has been used and parodied in various media and its best known line is an idiom of popular culture. In volume I of the 1812 annotations, it is listed as coming from Friedrich Schulz's Kleine Romane, Book 5, pp. 269–288, published in Leipzig 1790. In the Aarne–Thompson classification system for folktales it is type 310, "The Maiden in The Tower". Andrew Lang included it in The Red Fairy Book. Other versions of the tale appear in A Book of Witches by Ruth Manning-Sanders and in Paul O. Zelinsky's 1997 Caldecott Medal-winning picture book and the Disney movie Tangled.
Rapunzel's story has striking similarities to the Persian tale of Rudāba, included in the epic poem Shahnameh by Ferdowsi. Rudāba offers to let down her hair from her tower; some elements of the fairy tale might have been based upon the tale of Saint Barbara, said to have been locked in a tower by her father. Some researchers proposed a connection to pre-Christian European sun or dawn goddess myths, in which the light deity is trapped and is rescued. Similar myths include that of the Baltic solar goddess Saulė, held captive in a tower by a king. A lonely couple, who want a child, live next to a walled garden belonging to an evil witch named Dame Gothel; the wife, experiencing the cravings associated with the arrival of her long-awaited pregnancy, notices some rapunzel, growing in the garden and longs for it. She refuses to eat anything else and gets sick, the husband begins to fear for her life. One night, her husband breaks into the garden to get some for her, she greedily eats it. It tastes so good.
So her husband goes to get some more for her. As he scales the wall to return home, Dame Gothel accuses him of theft, he begs for mercy, she agrees to be lenient, allows him to take all the rapunzel he wants, on condition that the baby be given to her when it's born. Desperate, he agrees; when his wife has a baby girl, Dame Gothel takes her to raise as her own and names her Rapunzel after the plant her mother craved. She grows up to be the most beautiful child in the world with long golden hair; when she turns twelve, Dame Gothel locks her up inside a tower in the middle of the woods, with neither stairs nor a door, only one room and one window. In order to visit Rapunzel, Dame Gothel stands beneath the tower and calls out: Rapunzel, let down your hair! So, that I may climb thy golden stair. One day, a prince hears Rapunzel singing from the tower. Entranced by her ethereal voice, he searches for her and discovers the tower, but is unable to enter it, he returns listening to her beautiful singing, one day sees Dame Gothel visit, thus learns how to gain access to Rapunzel.
When Dame Gothel leaves, he bids Rapunzel let her hair down. When she does so, he climbs up and they fall in love, he asks her to marry him, which she agrees to. Together they plan a means of escape, wherein he will come each night, bring Rapunzel a piece of silk, which she will weave into a ladder. Before the plan can come to fruition, she foolishly gives him away. In the first edition of Grimm's Fairy Tales, she innocently says that her dress is growing tighter around her waist. In anger, she cuts off a majority of Rapunzel's hair and casts her out into the wilderness to fend for herself; when the prince calls that night, Dame Gothel lets the severed hair down to haul him up. To his horror, he finds himself meeting her instead of Rapunzel, nowhere to be found. After she tells him in a jealous rage that he will never see Rapunzel again, Gothel shoves him from the tower, sending him falling into a thorn bush, which blinds him. For months, he wanders through the wastelands of the country and comes to the wilderness where Rapunzel now lives with the twins she has given birth to, a boy and a girl.
One day, as she sings, he hears her voice again, they are reunited. When they fall into each other's arms, her tears restore his sight, he leads her and their twins to his kingdom, where they live ever after. In some versions of the story, Rapunzel's hair magically grows back after the prince touches it. Another version of the story ends with the revelation that Dame Gothel had untied Rapunzel's hair after the prince leapt from the tower, it slipped from her hands and landed far below, leaving her trapped in the tower; the uneven bargain with which "Rapunzel" opens is a common trope in fairy tales, replicated in "Jack and the Beanstalk", Jack trades a cow for beans, in "Beauty and the Beast", Beauty comes to the Beast in return for a rose. Folkloric beliefs regarded it as quite dangerous to deny a pregnant woman any food she craved. Family members would go to great lengths to secure such cravings; such desires for lettuce and like vegetables may indic
Phyteuma ovatum is a flowering plant in the family Campanulaceae
A perennial plant or perennial is a plant that lives more than two years. Some sources cite perennial plants being plants; the term is used to differentiate a plant from shorter-lived annuals and biennials. The term is widely used to distinguish plants with little or no woody growth from trees and shrubs, which are technically perennials. Perennials small flowering plants, that grow and bloom over the spring and summer, die back every autumn and winter, return in the spring from their rootstock, are known as herbaceous perennials. However, depending on the rigors of local climate, a plant, a perennial in its native habitat, or in a milder garden, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings or from divisions. Tomato vines, for example, live several years in their natural tropical/subtropical habitat but are grown as annuals in temperate regions because they don't survive the winter. There is a class of evergreen, or non-herbaceous, including plants like Bergenia which retain a mantle of leaves throughout the year.
An intermediate class of plants is known as subshrubs, which retain a vestigial woody structure in winter, e.g. Penstemon; the local climate may dictate whether plants are treated as perennials. For instance, many varieties of Fuchsia are shrubs in warm regions, but in colder temperate climates may be cut to the ground every year as a result of winter frosts; the symbol for a perennial plant, based on Species Plantarum by Linnaeus, is, the astronomical symbol for the planet Jupiter. Perennial plants can be short-lived or they can be long-lived, as are some woody plants like trees, they include a wide assortment of plant groups from ferns and liverworts to the diverse flowering plants like orchids and grasses. Plants that flower and fruit only once and die are termed monocarpic or semelparous. However, most perennials are polycarpic. Perennials grow structures that allow them to adapt to living from one year to the next through a form of vegetative reproduction rather than seeding; these structures include bulbs, woody crowns, rhizomes plus others.
They might have specialized stems or crowns that allow them to survive periods of dormancy over cold or dry seasons during the year. Annuals produce seeds to continue the species as a new generation while the growing season is suitable, the seeds survive over the cold or dry period to begin growth when the conditions are again suitable. Many perennials have developed specialized features that allow them to survive extreme climatic and environmental conditions; some have adapted to survive cold temperatures. Those plants tend to invest a lot of resource into their adaptations and do not flower and set seed until after a few years of growth. Many perennials produce large seeds, which can have an advantage, with larger seedlings produced after germination that can better compete with other plants; some annuals produce many more seeds per plant in one season, while some perennials are not under the same pressure to produce large numbers of seeds but can produce seeds over many years. Dividing perennial plants is something that gardeners do around the months of October.
The point of doing the division at this time is to allow 6 weeks for adequate root growth prior to the ground reaching a freezing temperature. Due to the leaves falling from trees, as well as the excessive amount of rain received in most places during the fall weeks, the ground has adequate moisture for rapid growth; each type of plant must be separated differently. However, plants such as Irises have a root system known as a Rhizomes, these root systems should be planted with the bulb of the plant just above ground level, with leaves from the following year showing; the point of dividing perennials is to increase the amount of a single breed of plant in your garden. The more you divide your perennial plants every year, the more vast your garden will grow. In warmer and more favorable climates, perennials grow continuously. In seasonal climates, their growth is limited to the growing season. In some species, perennials retain their foliage all year round. Other plants are deciduous perennials, for example, in temperate regions a perennial plant may grow and bloom during the warm part of the year, with the foliage dying back in the winter.
In many parts of the world, seasonality is expressed as wet and dry periods rather than warm and cold periods, deciduous perennials lose their leaves in the dry season. With their roots protected below ground in the soil layer, perennial plants are notably tolerant of wildfire. Herbaceous perennials are able to tolerate the extremes of cold in temperate and Arctic winters, with less sensitivity than trees or shrubs. Perennial plants can be differentiated from annuals and biennials in that perennials have the ability to remain dormant over long periods of time and continue growth and reproduction; the meristem of perennial plants communicates with the hormones produced due to environmental situations and stage of development to begin and halt the ability to grow or flower. There is a distinction between the ability to grow and actual task of growth. For example, most trees regain the ability to grow in the midst of winter but do not initiate physical growth until the spring and summer months.
The start of dormancy can be seen in perennials pla