1.
Megaannum
–
A year is the orbital period of the Earth moving in its orbit around the Sun. Due to the Earths axial tilt, the course of a year sees the passing of the seasons, marked by changes in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the globe, four seasons are recognized, spring, summer, autumn. In tropical and subtropical regions several geographical sectors do not present defined seasons, but in the seasonal tropics, a calendar year is an approximation of the number of days of the Earths orbital period as counted in a given calendar. The Gregorian, or modern, calendar, presents its calendar year to be either a common year of 365 days or a year of 366 days, as do the Julian calendars. For the Gregorian calendar the average length of the year across the complete leap cycle of 400 years is 365.2425 days. The ISO standard ISO 80000-3, Annex C, supports the symbol a to represent a year of either 365 or 366 days, in English, the abbreviations y and yr are commonly used. In astronomy, the Julian year is a unit of time, it is defined as 365.25 days of exactly 86400 seconds, totalling exactly 31557600 seconds in the Julian astronomical year. The word year is used for periods loosely associated with, but not identical to, the calendar or astronomical year, such as the seasonal year, the fiscal year. Similarly, year can mean the period of any planet, for example. The term can also be used in reference to any long period or cycle, west Saxon ġēar, Anglian ġēr continues Proto-Germanic *jǣran. Cognates are German Jahr, Old High German jār, Old Norse ár and Gothic jer, all the descendants of the Proto-Indo-European noun *yeh₁rom year, season. Cognates also descended from the same Proto-Indo-European noun are Avestan yārǝ year, Greek ὥρα year, season, period of time, Old Church Slavonic jarŭ, Latin annus is from a PIE noun *h₂et-no-, which also yielded Gothic aþn year. Both *yeh₁-ro- and *h₂et-no- are based on verbal roots expressing movement, *h₁ey- and *h₂et- respectively, the Greek word for year, ἔτος, is cognate with Latin vetus old, from the PIE word *wetos- year, also preserved in this meaning in Sanskrit vat-sa- yearling and vat-sa-ras year. Derived from Latin annus are a number of English words, such as annual, annuity, anniversary, etc. per annum means each year, anno Domini means in the year of the Lord. No astronomical year has an number of days or lunar months. Financial and scientific calculations often use a 365-day calendar to simplify daily rates, in the Julian calendar, the average length of a year is 365.25 days. In a non-leap year, there are 365 days, in a year there are 366 days
2.
Precambrian
–
The Precambrian is the earliest period of Earths history, set before the current Phanerozoic Eon. The Precambrian is a supereon that is subdivided into three eons of the time scale. It spans from the formation of Earth about 4.6 billion years ago to the beginning of the Cambrian Period, about 541 million years ago, the Precambrian accounts for 89% of geologic time. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earths history, the Precambrian fossil record is poorer than that of the succeeding Phanerozoic, and fossils from that time are of limited biostratigraphic use. This is because many Precambrian rocks have been metamorphosed, obscuring their origins, while others have been destroyed by erosion. A stable crust was apparently in place by 4,412 Ma, the term Precambrian is recognized by the International Commission on Stratigraphy as a general term including the Archean and Proterozoic eons. It is still used by geologists and paleontologists for general discussions not requiring the more specific eon names and it was briefly called the Cryptozoic eon. A specific date for the origin of life has not been determined, carbon found in 3.8 billion year old rocks from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have found in Western Australia. Probable fossils 100 million years older have been found in the same area, there is a fairly solid record of bacterial life throughout the remainder of the Precambrian. The oldest fossil evidence from that era of such complex life comes from the Lantian formation of the Ediacarian period, a very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota, hard-shelled creatures appeared toward the end of that time span, marking the beginning of the Phanerozoic era. By the middle of the following Cambrian period, a diverse fauna is recorded in the Burgess Shale. The explosion in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life, while land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Evidence of the details of plate motions and other activity in the Precambrian has been poorly preserved. It is generally believed that small proto-continents existed prior to 4280 Ma, the supercontinent, known as Rodinia, broke up around 750 Ma. A number of glacial periods have been identified going as far back as the Huronian epoch, one of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a Snowball Earth. The atmosphere of the early Earth is not well understood, most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and was lacking in free oxygen
3.
Cambrian
–
The Cambrian Period was the first geological period of the Paleozoic Era, of the Phanerozoic Eon. The Cambrian lasted 55.6 million years from the end of the preceding Ediacaran Period 541 million years ago to the beginning of the Ordovician Period 485.4 mya and its subdivisions, and its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latinised form of Cymru, the Welsh name for Wales, as a result, our understanding of the Cambrian biology surpasses that of some later periods. The rapid diversification of lifeforms in the Cambrian, known as the Cambrian explosion, most of the continents were probably dry and rocky due to a lack of vegetation. Shallow seas flanked the margins of several continents created during the breakup of the supercontinent Pannotia, the seas were relatively warm, and polar ice was absent for much of the period. The United States Federal Geographic Data Committee uses a barred capital C ⟨Є⟩ character similar to the capital letter Ukrainian Ye ⟨Є⟩ to represent the Cambrian Period, the proper Unicode character is U+A792 Ꞓ LATIN CAPITAL LETTER C WITH BAR. Despite the long recognition of its distinction from younger Ordovician Period rocks and older Supereon Precambrian rocks, the base of the Cambrian lies atop a complex assemblage of trace fossils known as the Treptichnus pedum assemblage. Pedum in Namibia, Spain and Newfoundland, and possibly, in the western USA, the stratigraphic range of T. pedum overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain. The Cambrian Period followed the Ediacaran Period and was followed by the Ordovician Period, the Cambrian is divided into four epochs and ten ages. Currently only two series and five stages are named and have a GSSP, because the international stratigraphic subdivision is not yet complete, many local subdivisions are still widely used. In some of these subdivisions the Cambrian is divided into three epochs with locally differing names – the Early Cambrian, Middle Cambrian and Furongian, rocks of these epochs are referred to as belonging to the Lower, Middle, or Upper Cambrian. Trilobite zones allow biostratigraphic correlation in the Cambrian, each of the local epochs is divided into several stages. The International Commission on Stratigraphy list the Cambrian period as beginning at 541 million years ago, the lower boundary of the Cambrian was originally held to represent the first appearance of complex life, represented by trilobites. The recognition of small shelly fossils before the first trilobites, and Ediacara biota substantially earlier and this formal designation allowed radiometric dates to be obtained from samples across the globe that corresponded to the base of the Cambrian. Early dates of 570 million years ago quickly gained favour, though the used to obtain this number are now considered to be unsuitable. A more precise date using modern radiometric dating yield a date of 541 ±0.3 million years ago, most continental land was clustered in the Southern Hemisphere at this time, but was drifting north. Large, high-velocity rotational movement of Gondwana appears to have occurred in the Early Cambrian, the sea levels fluctuated somewhat, suggesting there were ice ages, associated with pulses of expansion and contraction of a south polar ice cap. In Baltoscandia a Lower Cambrian transgression transformed large swathes of the Sub-Cambrian peneplain into a epicontinental sea, the Earth was generally cold during the early Cambrian, probably due to the ancient continent of Gondwana covering the South Pole and cutting off polar ocean currents
4.
Ordovician
–
The Ordovician is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.2 million years from the end of the Cambrian Period 485.4 million years ago to the start of the Silurian Period 443.8 Mya. Lapworth recognized that the fauna in the disputed strata were different from those of either the Cambrian or the Silurian periods. It received international sanction in 1960, when it was adopted as a period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian period, invertebrates, namely molluscs and arthropods, dominated the oceans. The Great Ordovician Biodiversification Event considerably increased the diversity of life, fish, the worlds first true vertebrates, continued to evolve, and those with jaws may have first appeared late in the period. Life had yet to diversify on land, about 100 times as many meteorites struck the Earth during the Ordovician compared with today. The Ordovician Period began with a major extinction called the Cambrian–Ordovician extinction event and it lasted for about 42 million years and ended with the Ordovician–Silurian extinction event, about 443.8 Mya which wiped out 60% of marine genera. The dates given are recent radiometric dates and vary slightly from those found in other sources and this second period of the Paleozoic era created abundant fossils that became major petroleum and gas reservoirs. The boundary chosen for the beginning of both the Ordovician Period and the Tremadocian stage is highly significant and it correlates well with the occurrence of widespread graptolite, conodont, and trilobite species. The base of the Tremadocian allows scientists to relate these species not only to each other and this makes it easier to place many more species in time relative to the beginning of the Ordovician Period. A number of terms have been used to subdivide the Ordovician Period. In 2008, the ICS erected an international system of subdivisions. There exist Baltoscandic, British, Siberian, North American, Australian, the Ordovician Period in Britain was traditionally broken into Early, Middle and Late epochs. The corresponding rocks of the Ordovician System are referred to as coming from the Lower, Middle, the Floian corresponds to the lower Arenig, the Arenig continues until the early Darriwilian, subsuming the Dapingian. The Llanvirn occupies the rest of the Darriwilian, and terminates with it at the base of the Late Ordovician. The Sandbian represents the first half of the Caradoc, the Caradoc ends in the mid-Katian, during the Ordovician, the southern continents were collected into Gondwana. Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole, the small continent Avalonia separated from Gondwana and began to move north towards Baltica and Laurentia, opening the Rheic Ocean between Gondwana and Avalonia
5.
Silurian
–
The Silurian is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago, to the beginning of the Devonian Period,419.2 Mya. As with other periods, the rock beds that define the periods start and end are well identified. The base of the Silurian is set at a major Ordovician-Silurian extinction event when 60% of marine species were wiped out, a significant evolutionary milestone during the Silurian was the diversification of jawed and bony fish. However, terrestrial life would not greatly diversify and affect the landscape until the Devonian, the Silurian system was first identified by British geologist Sir Roderick Impey Murchison, who was examining fossil-bearing sedimentary rock strata in south Wales in the early 1830s. He named the sequences for a Celtic tribe of Wales, the Silures, inspired by his friend Adam Sedgwick and this naming does not indicate any correlation between the occurrence of the Silurian rocks and the land inhabited by the Silures. As it was first identified, the Silurian series when traced farther afield quickly came to overlap Sedgwicks Cambrian sequence, however, charles Lapworth resolved the conflict by defining a new Ordovician system including the contested beds. An early alternative name for the Silurian was Gotlandian after the strata of the Baltic island of Gotland, the French geologist Joachim Barrande, building on Murchisons work, used the term Silurian in a more comprehensive sense than was justified by subsequent knowledge. He divided the Silurian rocks of Bohemia into eight stages and his interpretation was questioned in 1854 by Edward Forbes, and the later stages of Barrande, F, G and H, have since been shown to be Devonian. Despite these modifications in the groupings of the strata, it is recognized that Barrande established Bohemia as a classic ground for the study of the earliest fossils. The epoch is named for the town of Llandovery in Carmarthenshire, the Wenlock, which lasted from 433.4 ±1.5 to 427.4 ±2.8 mya, is subdivided into the Sheinwoodian and Homerian ages. It is named after Wenlock Edge in Shropshire, England, during the Wenlock, the oldest known tracheophytes of the genus Cooksonia, appear. The first terrestrial animals also appear in the Wenlock, represented by air-breathing millipedes from Scotland. The Ludlow, lasting from 427.4 ±1.5 to 423 ±2.8 mya, comprises the Gorstian stage, lasting until 425.6 million years ago, and it is named for the town of Ludlow in Shropshire, England. The Pridoli, lasting from 423 ±1.5 to 419.2 ±2.8 mya, is the final and it is named after one locality at the Homolka a Přídolí nature reserve near the Prague suburb Slivenec in the Czech Republic. Přídolí is the old name of a field area. The high sea levels of the Silurian and the flat land resulted in a number of island chains. The southern continents remained united during this period, the melting of icecaps and glaciers contributed to a rise in sea level, recognizable from the fact that Silurian sediments overlie eroded Ordovician sediments, forming an unconformity. The continents of Avalonia, Baltica, and Laurentia drifted together near the equator and this event is the Caledonian orogeny, a spate of mountain building that stretched from New York State through conjoined Europe and Greenland to Norway
6.
Devonian
–
The Devonian is a geologic period and system of the Paleozoic, spanning 60 million years from the end of the Silurian,419.2 million years ago, to the beginning of the Carboniferous,358.9 Mya. It is named after Devon, England, where rocks from this period were first studied, the first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents, by the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. Various terrestrial arthropods also became well-established, Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fish. The first ray-finned and lobe-finned bony fish appeared, while the placodermi began dominating almost every aquatic environment. The ancestors of all four-limbed vertebrates began adapting to walking on land, as their strong pectoral, in the oceans, primitive sharks became more numerous than in the Silurian and Late Ordovician. The first ammonites, species of molluscs, appeared, trilobites, the mollusk-like brachiopods and the great coral reefs, were still common. The Late Devonian extinction which started about 375 million years ago severely affected marine life, killing off all placodermi, and all trilobites, save for a few species of the order Proetida. The palaeogeography was dominated by the supercontinent of Gondwana to the south, the continent of Siberia to the north, while the rock beds that define the start and end of the Devonian period are well identified, the exact dates are uncertain. According to the International Commission on Stratigraphy, the Devonian extends from the end of the Silurian 419.2 Mya, another common term is Age of the Fishes, referring to the evolution of several major groups of fish that took place during the period. Older literature on the Anglo-Welsh basin divides it into the Downtonian, Dittonian, Breconian and Farlovian stages, in the Late Devonian, by contrast, arid conditions were less prevalent across the world and temperate climates were more common. The Devonian Period is formally broken into Early, Middle and Late subdivisions, the rocks corresponding to those epochs are referred to as belonging to the Lower, Middle and Upper parts of the Devonian System. Early Devonian The Early Devonian lasted from 419.2 ±2.8 to 393.3 ±2.5 and began with the Lochkovian stage, which lasted until the Pragian. It spanned from 410.8 ±2.8 to 407.6 ±2.5, and was followed by the Emsian, which lasted until the Middle Devonian began,393. 3±2.7 million years ago. Middle Devonian The Middle Devonian comprised two subdivisions, first the Eifelian, which gave way to the Givetian 387. 7±2.7 million years ago. Late Devonian Finally, the Late Devonian started with the Frasnian,382.7 ±2.8 to 372.2 ±2.5, during which the first forests took shape on land. The first tetrapods appeared in the record in the ensuing Famennian subdivision. This lasted until the end of the Devonian,358. 9±2.5 million years ago, the Devonian was a relatively warm period, and probably lacked any glaciers
7.
Carboniferous
–
The Carboniferous is a geologic period and system that spans 60 million years from the end of the Devonian Period 358.9 million years ago, to the beginning of the Permian Period,298.9 Mya. The name Carboniferous means coal-bearing and derives from the Latin words carbō and ferō, and was coined by geologists William Conybeare and William Phillips in 1822. Based on a study of the British rock succession, it was the first of the system names to be employed. The Carboniferous is often treated in North America as two periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial life was established by the Carboniferous period. Amphibians were the dominant land vertebrates, of one branch would eventually evolve into amniotes. Arthropods were also common, and many were much larger than those of today. Vast swaths of forest covered the land, which would eventually be laid down, the atmospheric content of oxygen also reached their highest levels in geological history during the period, 35% compared with 21% today, allowing terrestrial invertebrates to evolve to great size. A major marine and terrestrial extinction event, the Carboniferous rainforest collapse, occurred in the middle of the period, the later half of the period experienced glaciations, low sea level, and mountain building as the continents collided to form Pangaea. In the United States the Carboniferous is usually broken into Mississippian and Pennsylvanian subperiods, the Silesian is roughly contemporaneous with the late Mississippian Serpukhovian plus the Pennsylvanian. In Britain the Dinantian is traditionally known as the Carboniferous Limestone, the Namurian as the Millstone Grit, and the Westphalian as the Coal Measures and Pennant Sandstone. There was also a drop in south polar temperatures, southern Gondwanaland was glaciated throughout the period and these conditions apparently had little effect in the deep tropics, where lush swamps, later to become coal, flourished to within 30 degrees of the northernmost glaciers. Mid-Carboniferous, a drop in sea level precipitated a major extinction, one that hit crinoids. This sea level drop and the unconformity in North America separate the Mississippian subperiod from the Pennsylvanian subperiod. This happened about 323 million years ago, at the onset of the Permo-Carboniferous Glaciation, the Carboniferous was a time of active mountain-building, as the supercontinent Pangaea came together. The southern continents remained tied together in the supercontinent Gondwana, which collided with North America–Europe along the present line of eastern North America, in the same time frame, much of present eastern Eurasian plate welded itself to Europe along the line of the Ural mountains. Most of the Mesozoic supercontinent of Pangea was now assembled, although North China, the Late Carboniferous Pangaea was shaped like an O. There were two major oceans in the Carboniferous—Panthalassa and Paleo-Tethys, which was inside the O in the Carboniferous Pangaea, other minor oceans were shrinking and eventually closed - Rheic Ocean, the small, shallow Ural Ocean and Proto-Tethys Ocean
8.
Permian
–
The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 252.2 Mya. It is the last period of the Paleozoic Era, the following Triassic Period belongs to the Mesozoic Era, the concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. The Permian witnessed the diversification of the early amniotes into the groups of the mammals, turtles, lepidosaurs. The world at the time was dominated by two known as Pangaea and Siberia, surrounded by a global ocean called Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior, amniotes, who could better cope with these drier conditions, rose to dominance in place of their amphibian ancestors. The Permian ended with the Permian–Triassic extinction event, the largest mass extinction in Earths history, in which nearly 90% of marine species and it would take well into the Triassic for life to recover from this catastrophe. Recovery from the Permian-Triassic extinction event was protracted, on land, the term Permian was introduced into geology in 1841 by Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil, the region now lies in the Perm Krai of Russia. This could have in part caused the extinctions of marine species at the end of the period by severely reducing shallow coastal areas preferred by many marine organisms. During the Permian, all the Earths major landmasses were collected into a supercontinent known as Pangaea. The Cimmeria continent rifted away from Gondwana and drifted north to Laurasia, a new ocean was growing on its southern end, the Tethys Ocean, an ocean that would dominate much of the Mesozoic Era. Large continental landmass interiors experience climates with extreme variations of heat and cold, deserts seem to have been widespread on Pangaea. Such dry conditions favored gymnosperms, plants with seeds enclosed in a cover, over plants such as ferns that disperse spores in a wetter environment. The first modern trees appeared in the Permian, the climate in the Permian was quite varied. At the start of the Permian, the Earth was still in an Ice Age, glaciers receded around the mid-Permian period as the climate gradually warmed, drying the continents interiors. In the late Permian period, the drying continued although the temperature cycled between warm and cool cycles, Permian marine deposits are rich in fossil mollusks, echinoderms, and brachiopods. By the close of the Permian, trilobites and a host of other groups became extinct. Terrestrial life in the Permian included diverse plants, fungi, arthropods, the period saw a massive desert covering the interior of Pangaea
9.
Triassic
–
The Triassic is a geologic period and system which spans 50.9 million years from the end of the Permian Period 252.17 million years ago, to the beginning of the Jurassic Period 201.3 Mya. The Triassic is the first period of the Mesozoic Era, both the start and end of the period are marked by major extinction events. Therapsids and archosaurs were the terrestrial vertebrates during this time. A specialized subgroup of archosaurs, called dinosaurs, first appeared in the Late Triassic, the vast supercontinent of Pangaea existed until the mid-Triassic, after which it began to gradually rift into two separate landmasses, Laurasia to the north and Gondwana to the south. The global climate during the Triassic was mostly hot and dry, however, the climate shifted and became more humid as Pangaea began to drift apart. The end of the period was marked by yet another mass extinction, the Triassic-Jurassic extinction event. The Triassic is usually separated into Early, Middle, and Late Triassic Epochs, from the east, along the equator, the Tethys sea penetrated Pangaea, causing the Paleo-Tethys Ocean to be closed. Later in the mid-Triassic a similar sea penetrated along the equator from the west, the remaining shores were surrounded by the world-ocean known as Panthalassa. All the deep-ocean sediments laid down during the Triassic have disappeared through subduction of oceanic plates, thus, the supercontinent Pangaea was rifting during the Triassic—especially late in that period—but had not yet separated. In North America, for example, marine deposits are limited to a few exposures in the west, thus Triassic stratigraphy is mostly based on organisms that lived in lagoons and hypersaline environments, such as Estheria crustaceans. At the beginning of the Mesozoic Era, Africa was joined with Earths other continents in Pangaea, Africa shared the supercontinents relatively uniform fauna which was dominated by theropods, prosauropods and primitive ornithischians by the close of the Triassic period. Late Triassic fossils are found throughout Africa, but are common in the south than north. The time boundary separating the Permian and Triassic marks the advent of an event with global impact. At Paleorrota geopark, located in Rio Grande do Sul, Brazil, in these formations, one of the earliest dinosaurs, Staurikosaurus, as well as the mammal ancestors Brasilitherium and Brasilodon have been discovered. The Triassic continental interior climate was hot and dry, so that typical deposits are red bed sandstones and evaporites. Pangaeas large size limited the effect of the global ocean, its continental climate was highly seasonal, with very hot summers. The strong contrast between the Pangea supercontinent and the global ocean triggered intense cross-equatorial monsoons, the best studied of such episodes of humid climate, and probably the most intense and widespread, was the Carnian Pluvial Event. On land, the vascular plants included the lycophytes, the dominant cycadophytes, ginkgophyta, ferns, horsetails
10.
Jurassic
–
The Jurassic is a geologic period and system that spans 56.3 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era, also known as the Age of Reptiles, the start of the period is marked by the major Triassic–Jurassic extinction event. The Jurassic is named after the Jura Mountains within the European Alps, by the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses, Laurasia to the north and Gondwana to the south. This created more coastlines and shifted the continental climate from dry to humid, on land, the fauna transitioned from the Triassic fauna, dominated by both dinosauromorph and crocodylomorph archosaurs, to one dominated by dinosaurs alone. The first birds also appeared during the Jurassic, having evolved from a branch of theropod dinosaurs, other major events include the appearance of the earliest lizards, and the evolution of therian mammals, including primitive placentals. Crocodilians made the transition from a terrestrial to a mode of life. The oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, the chronostratigraphic term Jurassic is directly linked to the Jura Mountains. The name Jura is derived from the Celtic root jor, which was Latinised into juria, the Jurassic period is divided into the Early Jurassic, Middle, and Late Jurassic epochs. The Jurassic System, in stratigraphy, is divided into the Lower Jurassic, Middle, the separation of the term Jurassic into three sections goes back to Leopold von Buch. The Jurassic North Atlantic Ocean was relatively narrow, while the South Atlantic did not open until the following Cretaceous period, the Tethys Sea closed, and the Neotethys basin appeared. Climates were warm, with no evidence of glaciation, as in the Triassic, there was apparently no land over either pole, and no extensive ice caps existed. In contrast, the North American Jurassic record is the poorest of the Mesozoic, the Jurassic was a time of calcite sea geochemistry in which low-magnesium calcite was the primary inorganic marine precipitate of calcium carbonate. Carbonate hardgrounds were thus very common, along with calcitic ooids, calcitic cements, the first of several massive batholiths were emplaced in the northern American cordillera beginning in the mid-Jurassic, marking the Nevadan orogeny. Important Jurassic exposures are found in Russia, India, South America, Japan, Australasia. As the Jurassic proceeded, larger and more groups of dinosaurs like sauropods and ornithopods proliferated in Africa. Middle Jurassic strata are well represented nor well studied in Africa. Late Jurassic strata are also poorly represented apart from the spectacular Tendaguru fauna in Tanzania, the Late Jurassic life of Tendaguru is very similar to that found in western North Americas Morrison Formation. During the Jurassic period, the primary living in the sea were fish
11.
Cretaceous
–
The Cretaceous is a geologic period and system that spans 79 million years from the end of the Jurassic Period 145 million years ago to the beginning of the Paleogene Period 66 Mya. It is the last period of the Mesozoic Era, the Cretaceous Period is usually abbreviated K, for its German translation Kreide. The Cretaceous was a period with a warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles, ammonites and rudists, during this time, new groups of mammals and birds, as well as flowering plants, appeared. The Cretaceous ended with a mass extinction, the Cretaceous–Paleogene extinction event, in which many groups, including non-avian dinosaurs, pterosaurs. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary, the name Cretaceous was derived from Latin creta, meaning chalk. The Cretaceous is divided into Early and Late Cretaceous epochs, or Lower and Upper Cretaceous series, in older literature the Cretaceous is sometimes divided into three series, Neocomian, Gallic and Senonian. A subdivision in eleven stages, all originating from European stratigraphy, is now used worldwide, in many parts of the world, alternative local subdivisions are still in use. As with other geologic periods, the rock beds of the Cretaceous are well identified. No great extinction or burst of diversity separates the Cretaceous from the Jurassic and this layer has been dated at 66.043 Ma. A140 Ma age for the Jurassic-Cretaceous boundary instead of the usually accepted 145 Ma was proposed in 2014 based on a study of Vaca Muerta Formation in Neuquén Basin. Víctor Ramos, one of the authors of the study proposing the 140 Ma boundary age sees the study as a first step toward formally changing the age in the International Union of Geological Sciences, due to the high sea level there was extensive space for such sedimentation. Because of the young age and great thickness of the system. Chalk is a type characteristic for the Cretaceous. It consists of coccoliths, microscopically small calcite skeletons of coccolithophores, the group is found in England, northern France, the low countries, northern Germany, Denmark and in the subsurface of the southern part of the North Sea. Chalk is not easily consolidated and the Chalk Group still consists of sediments in many places. The group also has other limestones and arenites, among the fossils it contains are sea urchins, belemnites, ammonites and sea reptiles such as Mosasaurus. In southern Europe, the Cretaceous is usually a marine system consisting of competent limestone beds or incompetent marls
12.
Paleogene
–
The Paleogene is a geologic period and system that spans 43 million years from the end of the Cretaceous Period 66 million years ago to the beginning of the Neogene Period 23.03 Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon and this period consists of the Paleocene, Eocene and Oligocene epochs. The terms Paleogene System and lower Tertiary System are applied to the rocks deposited during the Paleogene Period. By dividing the Tertiary Period into two periods instead of directly into five epochs, the periods are more comparable to the duration of periods of the preceding Mesozoic and Paleozoic Eras. The trend was caused by the formation of the Antarctic Circumpolar Current. During the Paleogene, the continued to drift closer to their current positions. India was in the process of colliding with Asia, subsequently forming the Himalayas, the Atlantic Ocean continued to widen by a few centimeters each year. Africa was moving north to meet with Europe and form the Mediterranean, inland seas retreated from North America early in the period. Australia had also separated from Antarctica and was drifting towards Southeast Asia, mammals began a rapid diversification during this period. Some of these mammals would evolve into forms that would dominate the land, while others would become capable of living in marine, specialized terrestrial. Those that took to the oceans became modern cetaceans, while those that took to the trees became primates, the group to which humans belong. Birds, which were well established by the end of the Cretaceous. In comparison to birds and mammals, most other branches of life remained unchanged during this period. As the Earth cooled, tropical plants became less numerous and were now restricted to equatorial regions, deciduous plants, which could survive through the seasonal climates the world was now experiencing, became more common. The Paleogene is notable in the context of offshore oil drilling, and especially in Gulf of Mexico oil exploration and these rock formations represent the current cutting edge of deep-water oil discovery. Lower Tertiary explorations to date include, Kaskida Oil Field Tiber Oil Field Jack 2 Paleogene Microfossils, 180+ images of Foraminifera
13.
Neogene
–
The Neogene is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.03 million years ago to the beginning of the present Quaternary Period 2.58 Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene, some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. During this period, mammals and birds continued to evolve into modern forms. Early hominids, the ancestors of humans, appeared in Africa near the end of the period, some continental movement took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the ocean currents from the Pacific to the Atlantic ocean. The global climate cooled considerably over the course of the Neogene, the terms Neogene System and upper Tertiary System describe the rocks deposited during the Neogene Period. The continents in the Neogene were very close to their current positions, the Isthmus of Panama formed, connecting North and South America. The Indian subcontinent continued to collide with Asia, forming the Himalayas, sea levels fell, creating land bridges between Africa and Eurasia and between Eurasia and North America. The global climate became seasonal and continued an overall drying and cooling trend which began at the start of the Paleogene. The ice caps on both poles began to grow and thicken, and by the end of the period the first of a series of glaciations of the current Ice Age began, marine and continental flora and fauna have a modern appearance. The reptile group Choristodera became extinct in the part of the period. Mammals and birds continued to be the dominant terrestrial vertebrates, the first hominids, the ancestors of humans, appeared in Africa and spread into Eurasia. In response to the cooler, seasonal climate, tropical plant species gave way to deciduous ones, grasses therefore greatly diversified, and herbivorous mammals evolved alongside it, creating the many grazing animals of today such as horses, antelope, and bison. The Neogene traditionally ended at the end of the Pliocene Epoch, just before the definition of the beginning of the Quaternary Period. However, there was a movement amongst geologists to also include ongoing geological time in the Neogene, by dividing the Cenozoic Era into three periods instead of seven epochs, the periods are more closely comparable to the duration of periods in the Mesozoic and Paleozoic eras. The International Commission on Stratigraphy once proposed that the Quaternary be considered a sub-era of the Neogene, with a date of 2.58 Ma. In the 2004 proposal of the ICS, the Neogene would have consisted of the Miocene and Pliocene epochs, thus the Neogene Period ends bounding the succeeding Quaternary Period at 2.58 Mya. Digital Atlas of Neogene Life for the Southeastern United States — by San Jose State University via Web Archive
14.
Nymphaea nouchali
–
Nymphaea nouchali, often known by its synonym Nymphaea stellata, or by common names blue lotus, star lotus, red and blue water lily, or blue star water lily is a water lily of genus Nymphaea. It is native to southern and eastern parts of Asia, and is the flower of Sri Lanka. This species is considered to include the blue Egyptian lotus Nymphaea caerulea. In the past, taxonomic confusion has occurred, with the name Nymphaea nouchali incorrectly applied to Nymphaea pubescens and this aquatic plant is native in a broad region from Afghanistan, the Indian subcontinent, to Taiwan, southeast Asia, and Australia. It has been valued as a garden flower in Thailand and Myanmar to decorate ponds. In its natural state, N. nouchali is found in static or slow-flowing aquatic habitats of low to moderate depth, N. nouchali is a day-blooming nonviviparous plant with submerged roots and stems. Part of the leaves are submerged, while others rise slightly above the surface, the leaves are round and green on top, they usually have a darker underside. The floating leaves have undulating edges that give them a crenellated appearance and their size is about 20–23 cm and their spread is 0.9 to 1.8 m. This water lily has a flower which is usually violet blue in color with reddish edges. Some varieties have white, purple, mauve, or fuchsia-colored flowers, hence its name red, the flower has four or five sepals and 13-15 petals that have an angular appearance, making the flower look star-shaped from above. The cup-like calyx has a diameter of 11–14 cm and it was also the National flower of the former defunct Hyderabad State. N. nouchali is the flower of Bangladesh. A pale blue-flowered N. nouchali is the flower of Sri Lanka. In Sri Lanka, this plant usually grows in buffalo ponds, buddhist lore in Sri Lanka claims that this flower was one of the 108 auspicious signs found on Prince Siddharthas footprint. It is said that when Buddha died, lotus flowers blossomed everywhere he had walked in his lifetime, N. nouchali might have been one of the plants eaten by the Lotophagi of Homers Odyssey. N. nouchali is used as a plant because of its spectacular flowers. It is also popular as a plant under the name dwarf lily or dwarf red lily. Sometimes, it is grown for its flowers, while other aquarists prefer to trim the lily pads, N. nouchali is considered a medicinal plant in Indian Ayurvedic medicine under the name ambal, it was mainly used to treat indigestion
15.
Taxonomy (biology)
–
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
16.
Plant
–
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
17.
Flowering plant
–
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
18.
Nymphaeales
–
The Nymphaeales are an order of flowering plants, consisting of three families of aquatic plants, the Hydatellaceae, the Cabombaceae, and the Nymphaeaceae. It is one of the three orders of basal angiosperms, a grade of flowering plants. At least 10 morphological characters unite the Nymphaeales, the difference in species numbers is due almost entirely to the difficulty of delineating species in the genus Nymphaea. All of the species are rhizomatous aquatic herbs with a broad base and large. The fossil record consists especially of seeds, but also pollen, stems, leaves and it extends back to the Cretaceous. The crown group of the Nymphaeales has been estimated to be about 112 million years old, some have suggested that this age might be too old. The aquatic plant fossil Archaefructus possibly belongs to this group, the Nymphaeales currently include three families and about 70 to 90 species. This order was not part of the APG II systems 2003 plant classification, the APG III system did separate the Cabombaceae from the Nymphaeaceae and placed them in the order Nymphaeales together with the Hydatellaceae. This familyHydatellaceae was placed among the monocots in previous systems, but a 2007 study found that the belongs to the Nymphaeales. Some earlier systems, such as Cronquists system of 1981, often included the Ceratophyllaceae and Nelumbonaceae in the Nymphaeales, although, the Takhtajan system of 1980 separated the Nelumbonales, the new order was retained alongside the Nymphaeales in the superorder Nymphaeanae. The Cronquist system placed the Nymphaeales in subclass Magnoliidae, in class Magnoliopsida, in addition, Cronquist included the Ceratophyllaceae and split the family Barclayaceae from the Nymphaeaceae. Under the APG II system, the family Cambombaceae was included within the Nymphaeaceae, as of APG III, the two families are recognized separately. The Dahlgren system placed the Nymphaeales with the Piperales in superorder Nymphaeanae, thornes 1992 system placed the Nymphaeales as the sole order in the superorder Nymphaeanae within subclass Magnoliideae. Thomas N. Taylor, Edith L. Taylor, and Michael Krings, paleobotany, The Biology and Evolution of Fossil Plants, Second Edition. ISBN 978-0-12-373972-8 Nymphaeales At, Angiosperm Phylogeny Website At, botanical databases At, Plant Science At, Missouri Botanical Garden Data related to Nymphaeales at Wikispecies
19.
Euryale ferox
–
Euryale ferox is the only extant species in the genus Euryale. It is a flowering plant classified in the lily family, Nymphaeaceae. Unlike other water lilies, the grains of Euryale have three nuclei. Euryale is a plant native to eastern Asia, and is found from India- found in Bihar. It grows in water, producing bright purple flowers, the leaves are large and round, often more than a meter across, with a leaf stalk attached in the center of the lower surface. The underside of the leaf is purplish, while the surface is green. The leaves have a texture, although the stems, flowers. In India, Euryale normally grows in ponds, wetlands etc, recently the Indian Council of Agricultural Research have developed a technique for the field cultivation of Euryale. The plant produces starchy white seeds that are edible, the plant is cultivated for its seeds in lowland ponds in India, China, and Japan. The Chinese have cultivated the plant for over 3000 years, more than 96,000 hectares of Bihar, India, were set aside for cultivation of Euryale in 1990-1991. The plant grows best in locations with hot, dry summers, seeds are collected in the late summer and early autumn, and may be eaten raw or cooked. In India, in the northern and western parts of the country, Euryale ferox seeds are roasted or fried. These are then eaten, often with a sprinkling of oil, makhhaan along with Paan and Maachch is symbolic to Maithil culture. The earliest recorded use of E. ferox was found in Gesher Benot Yaaqov, Israel, the seeds of foxnut are used in ayurvedic preparations. In Chinese, the plant is called qiàn shí and its edible seeds are used in traditional Chinese medicine, where they are often cooked in soups along with other ingredients. The name Euryale comes from the mythical Greek Gorgon by the same name, the Soviet Union issued a postage stamp featuring this species. Euryale ferox page Fox nut page Euryale seed page Gordon Euryale page Information regarding possibly health benefits of Euryale ferox seeds
20.
Nuphar
–
Nuphar is genus of aquatic plants in the family Nymphaeaceae, with a temperate to subarctic Northern Hemisphere distribution. Common names include water-lily, pond-lily, alligator-bonnet or bonnet lily, the etymology of the word is, medieval Latin nuphar, from medieval Latin nenuphar, thence from Arabic nīnūfar, thence from Persian nīlūfar, thence from Sanskrit nīlōtpala = blue lotus flower. For botanical gender, the name is treated as feminine, the genus is closely related to Nymphaea. Nuphar differs in that its petals are smaller than its 4-6 bright yellow-coloured sepals, whereas in Nymphaea. In both genera the leaves float and have a notch from the circumference to the point of attachment of the petiole. Depending on the species, the leaves of most species range from cordate to practically circular with the petiole attached in the middle, some however, have modified versions of that leaf morphology, for example the leaves of Nuphar sagittifolia have leaves of an elongated sagittate form. The number of species in the genus is still under review, molecular taxonomy has shown conclusively that recognition of so few species is out of the question, and forced an increased number of recognised species, some sources list about seventy. The Kew Gardens plant list includes over twenty accepted species, subspecies and varieties, it also has a number as yet unresolved. Nuphar Section Astylus Nuphar advena W. T. Aiton –Spatterdock Nuphar azarkana †Nuphar carlquistii DeVore, Taylor, Nuphar sagittifolia Pursh Nuphar ulvaca Nuphar variegata Engelm. Ex Durand – Variegated pond-lily Nuphar Section Nuphar Nuphar japonica DC, – Yellow water-lily Nuphar microphylla Nuphar pumila DC. – Least water-lily There also are several interspecific hybrids, Nuphar species occur in ponds, lakes, and slow-moving rivers, growing in water up to 5 metres deep, different species are variously adaptated either to nutrient-rich waters or nutrient-poor waters. Wetland soils are hypoxic, and this genus is known to be capable of growth even in the absence of oxygen. Also there can be mass flow of oxygen-containing air, entering by means of the leaves, passing through the rhizome. Both of these adaptations to flooding are considered typical of many wetland. They also produce alkaloids that have experimentally shown to be allelopathic. Birds such as species of ducks eat Nuphar seeds, and mammals such as beaver. Deer eat flowers and young leaves, Nuphar species are less generally useful as food or medicine than various species in the related water lily genus Nymphaea. However, some species have used by indigenous peoples
21.
Nymphaea
–
Nymphaea /nɪmˈfiːə/ is a genus of hardy and tender aquatic plants in the family Nymphaeaceae. The genus has a cosmopolitan distribution, many species are cultivated as ornamental plants, and many cultivars have been bred. Some taxa occur as introduced species where they are not native, plants of the genus are known commonly as water lilies. The genus name is from the Greek νυμφαια, nymphaia and the Latin nymphaea, water lilies are aquatic rhizomatous perennial herbs, sometimes with stolons, as well. The leaves grow from the rhizome on long petioles, most of them float on the surface of the water. The blades have smooth or spine-toothed edges, and they can be rounded or pointed, the flowers rise out of the water or float on the surface, opening during the day or at night. Many species of Nymphaea display protogynous flowering, each has at least eight petals in shades of white, pink, blue, or yellow. Many stamens are at the center, water lily flowers are entomophilous, meaning they are pollinated by insects, often beetles. The fruit is berry-like and borne on a curving or coiling peduncle, water lilies are not only decorative, but also provide useful shade which helps reduce the growth of algae in ponds and lakes. Many of the water lilies familiar in water gardening are hybrids, the young leaves and unopened flower buds can be boiled and served as a vegetable. The seeds, high in starch, protein, and oil, may be popped, parched, potato-like tubers can be collected from the species N. tuberosa. This is one of several genera of plants known commonly as lotuses and it is not related to the legume genus Lotus or the Chinese and Indian lotuses of genus Nelumbo. It is closely related to Nuphar lotuses, however, in Nymphaea, the petals are much larger than the sepals, whereas in Nuphar, the petals are much smaller. The process of fruit maturation also differs, with Nymphaea fruit sinking below the level immediately after the flower closes. The lotus motif is a frequent feature of temple column architecture, the flowers of the blue Egyptian water lily open in the morning and then sink beneath the water at dusk, while those of the white water lily open at night and close in the morning. Egyptians found this symbolic of the separation of deities and of death, remains of both flowers have been found in the burial tomb of Ramesses II. A Roman belief existed that drinking a liquid of crushed Nymphaea in vinegar for 10 consecutive days turned a boy into a eunuch, a Syrian terra-cotta plaque from the 14th-13th centuries BC shows the goddess Asherah holding two lotus blossoms. An ivory panel from the 9th-8th centuries BC shows the god Horus seated on a lotus blossom, the French Impressionist painter Claude Monet is known for his many paintings of water lilies in the pond in his garden at Giverny
22.
Victoria (plant)
–
Victoria is a genus of water-lilies, in the plant family Nymphaeaceae, with very large green leaves that lie flat on the waters surface. Victoria amazonica has a leaf that is up to 3 metres in diameter, the genus name was given in honour of Queen Victoria of the United Kingdom. Victoria amazonica is native to the waters of the Amazon River basin, such as oxbow lakes. It is depicted in the Guyanese coat of arms, the flowers are white the first night they are open and become pink the second night. They are up to 40 cm in diameter, and are pollinated by scarab beetles, V. cruziana opens its flowers at dusk. The first published description of the genus was by John Lindley in 1837, Lindley named the genus after the new Queen, Victoria, and the species Victoria regia. An earlier account of the species, Euryale amazonica Poeppig, in 1832 described an affinity with Euryale ferox, a collection and description was also made by the French botanist Aimé Bonpland in 1825. To counter the fragile nature of the leaf, the needs to be distributed across the surface through mechanical means. This allows the leaf to support up to 32 kilograms, giant waterlily at the Royal Botanic Gardens, Kew
23.
Victoria cruziana
–
Victoria cruziana is a tropical species of flowering plant, of the Nymphaeaceae family of water lilies native to South America, primarily Argentina and Paraguay. The plant is a water garden plant in botanical gardens where its very large leaves can reach their fullest. It can be grown in cooler waters than its sister within the genus, a 25 cm diameter flower blooms for two days, arising from the underwater bud, as a white flower that turns to a deep pink on the second and final day of its bloom. V. cruziana is a thermogenetic or heat-producing plant, Victoria cruziana was discovered in Bolivia on one of many expeditions through the country by Alcide dOrbigny whose presence was sponsored by Andrés de Santa Cruz. The first collected specimens were returned to France where they named in honor of Santa Cruz by Alcides brother, Charles Henry Dessalines dOrbigny
24.
Rhizome
–
In botany and dendrology, a rhizome is a modified subterranean stem of a plant that is usually found underground, often sending out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks and rootstocks, Rhizomes develop from axillary buds and are diageotropic or grow perpendicular to the force of gravity. The rhizome also retains the ability to new shoots to grow upwards. If a rhizome is separated into pieces, each piece may be able to rise to a new plant. The plant uses the rhizome to store starches, proteins, and these nutrients become useful for the plant when new shoots must be formed or when the plant dies back for the winter. This is a known as vegetative reproduction and is used by farmers and gardeners to propagate certain plants. This also allows for lateral spread of grasses like bamboo and bunch grasses, examples of plants that are propagated this way include hops, asparagus, ginger, irises, Lily of the Valley, cannas, and sympodial orchids. Some rhizomes which are used directly in cooking include ginger, turmeric, galangal, stored rhizomes are subject to bacterial and fungal infections, making them unsuitable for replanting and greatly diminishing stocks. However, rhizomes can also be produced artificially from tissue cultures, the ability to easily grow rhizomes from tissue cultures leads to better stocks for replanting and greater yields. The plant hormones ethylene and jasmonic acid have found to help induce and regulate the growth of rhizomes. Ethylene that was applied externally was found to affect internal ethylene levels, knowledge of how to use these hormones to induce rhizome growth could help farmers and biologists producing plants grown from rhizomes more easily cultivate and grow better plants. The poplars are an example of trees that propagate using a rhizome, the Pando colony in Utah is a famous example, which has been living for about 80,000 years. In general, rhizomes have short internodes, they send out roots from the bottom of the nodes, a stem tuber is a thickened part of a rhizome or stolon that has been enlarged for use as a storage organ. In general, a tuber is high in starch, for example, the common potato, the term tuber is often used imprecisely, and is sometimes applied to plants with rhizomes. Some plants have rhizomes that grow above ground or that lie at the surface, including some Iris species. Rhizomes generally form a layer, but in Giant Horsetails. Many rhizomes have culinary value, and some, such as zheergen, are consumed raw. Aspen Corm Mycorrhiza Media related to Rhizomes at Wikimedia Commons
25.
Tropics
–
The tropics are a region of the Earth surrounding the equator. The tropics are also referred to as the zone and the torrid zone. The tropics include all the areas on the Earth where the Sun is at a point directly overhead at least once during the solar year. The tropics are distinguished from the climatic and biomatic regions of Earth, which are the middle latitudes. Tropical is sometimes used in a sense for a tropical climate to mean warm to hot and moist year-round. Many tropical areas have a dry and wet season, the wet season, rainy season or green season, is the time of year, ranging from one or more months, when most of the average annual rainfall in a region falls. Areas with wet seasons are disseminated across portions of the tropics and subtropics, under the Köppen climate classification, for tropical climates, a wet season month is defined as a month where average precipitation is 60 millimetres or more. Tropical rainforests technically do not have dry or wet seasons, since their rainfall is distributed through the year. When the wet season occurs during the season, or summer, precipitation falls mainly during the late afternoon. The wet season is a time when air quality improves, freshwater quality improves and vegetation grows significantly, floods cause rivers to overflow their banks, and some animals to retreat to higher ground. Soil nutrients diminish and erosion increases, the incidence of malaria increases in areas where the rainy season coincides with high temperatures. Animals have adaptation and survival strategies for the wetter regime, unfortunately, the previous dry season leads to food shortages into the wet season, as the crops have yet to mature. Regions within the tropics may well not have a tropical climate, there are alpine tundra and snow-capped peaks, including Mauna Kea, Mount Kilimanjaro, and the Andes as far south as the northernmost parts of Chile and Argentina. Under the Köppen climate classification, much of the area within the tropics is classed not as tropical but as dry including the Sahara Desert. Tropical plants and animals are those native to the tropics. Tropical ecosystems may consist of rainforests, dry forests, spiny forests, desert. There are often significant areas of biodiversity, and species present, particularly in rainforests. In biogeography, the tropics are divided into Paleotropics and Neotropics, together, they are sometimes referred to as the Pantropic
26.
Soil
–
Soil is a mixture of minerals, organic matter, gases, liquids, and countless organisms that together support life on Earth. Soil is called the Skin of the Earth and interfaces with the lithosphere, the hydrosphere, the atmosphere, the term pedolith, used commonly to refer to the soil, literally translates ground stone. Soil consists of a phase of minerals and organic matter, as well as a porous phase that holds gases. Accordingly, soils are often treated as a system of solids, liquids. Soil is a product of the influence of climate, relief, organisms, Soil continually undergoes development by way of numerous physical, chemical and biological processes, which include weathering with associated erosion. Given its complexity and strong internal connectedness soil has been considered as an ecosystem by soil ecologists. Most soils have a dry bulk density between 1.1 and 1.6 g/cm3, while the particle density is much higher. Little of the soil of planet Earth is older than the Pleistocene and none is older than the Cenozoic, Soil science has two basic branches of study, edaphology and pedology. Edaphology is concerned with the influence of soils on living things, pedology is focused on the formation, description, and classification of soils in their natural environment. In engineering terms, soil is referred to as regolith, or loose material that lies above the solid geology. Soil is commonly referred to as earth or dirt, technically, as soil resources serve as a basis for food security, the international community advocates its sustainable and responsible use through different types of soil governance. Soil is a component of the Earths ecosystem. The worlds ecosystems are impacted in far-reaching ways by the carried out in the soil, from ozone depletion and global warming, to rainforest destruction. Following the atmosphere, the soil is the next largest carbon reservoir on Earth, as the planet warms, soils will add carbon dioxide to the atmosphere due to its increased biological activity at higher temperatures. Thus, soil carbon losses likely have a positive feedback response to global warming. Since soil has a range of available niches and habitats. A gram of soil can contain billions of organisms, belonging to thousands of species, mostly microbial, Soil has a mean prokaryotic density of roughly 108 organisms per gram, whereas the ocean has no more than 107 procaryotic organisms per milliliter of seawater. Since plant roots need oxygen, ventilation is an important characteristic of soil and this ventilation can be accomplished via networks of interconnected soil pores, which also absorb and hold rainwater making it readily available for plant uptake
27.
Leaf
–
A leaf is an organ of a vascular plant and is the principal lateral appendage of the stem. The leaves and stem together form the shoot, Leaves are collectively referred to as foliage, as in autumn foliage. Although leaves can be seen in different shapes, sizes and textures, typically a leaf is a thin, dorsiventrally flattened organ, borne above ground. Most leaves have distinctive upper surface and lower surface that differ in colour, hairiness, broad, flat leaves with complex venation are known as megaphylls and the species that bear them, the majority, as broad-leaved or megaphyllous plants. In others, such as the clubmosses, with different evolutionary origins, some leaves, such as bulb scales are not above ground, and in many aquatic species the leaves are submerged in water. Succulent plants often have thick juicy leaves, but some leaves are without major photosynthetic function and may be dead at maturity, as in some cataphylls, furthermore, several kinds of leaf-like structures found in vascular plants are not totally homologous with them. Examples include flattened plant stems called phylloclades and cladodes, and flattened leaf stems called phyllodes which differ from both in their structure and origin. Many structures of plants, such as the phyllids of mosses and liverworts and even of some foliose lichens. Leaves are the most important organs of most vascular plants and these are then further processed by chemical synthesis into more complex organic molecules such as cellulose, the basic structural material in plant cell walls. The plant must therefore bring these three together in the leaf for photosynthesis to take place. Once sugar has been synthesized, it needs to be transported to areas of growth such as the plant shoots and roots. Vascular plants transport sucrose in a tissue called the phloem. The phloem and xylem are parallel to each other but the transport of materials is usually in opposite directions. Within the leaf these vascular systems branch to form veins which supply as much as the leaf as possible and they are arranged on the plant so as to expose their surfaces to light as efficiently as possible without shading each other, but there are many exceptions and complications. For instance plants adapted to windy conditions may have pendent leaves, such as in many willows, the flat, or laminar, shape also maximises thermal contact with the surrounding air, promoting cooling. Functionally, in addition to photosynthesis the leaf is the site of transpiration and guttation. Many gymnosperms have thin needle-like or scale-like leaves that can be advantageous in cold climates with frequent snow and these are interpreted as reduced from megaphyllous leaves of their Devonian ancestors. For xerophytes the major constraint is not light flux or intensity, some window plants such as Fenestraria species and some Haworthia species such as Haworthia tesselata and Haworthia truncata are examples of xerophytes. and Bulbine mesembryanthemoides
28.
Flower
–
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in plants that are floral. The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs, Flowers may facilitate outcrossing or allow selfing. Some flowers produce diaspores without fertilization, Flowers contain sporangia and are the site where gametophytes develop. Many flowers have evolved to be attractive to animals, so as to them to be vectors for the transfer of pollen. After fertilization, the ovary of the flower develops into fruit containing seeds, the essential parts of a flower can be considered in two parts, the vegetative part, consisting of petals and associated structures in the perianth, and the reproductive or sexual parts. A stereotypical flower consists of four kinds of structures attached to the tip of a short stalk, each of these kinds of parts is arranged in a whorl on the receptacle. The four main whorls are as follows, Collectively the calyx, corolla, the next whorl toward the apex, composed of units called petals, which are typically thin, soft and colored to attract animals that help the process of pollination. Androecium, the whorl, consisting of units called stamens. Stamens consist of two parts, a called a filament, topped by an anther where pollen is produced by meiosis. Gynoecium, the innermost whorl of a flower, consisting of one or more units called carpels, the carpel or multiple fused carpels form a hollow structure called an ovary, which produces ovules internally. Ovules are megasporangia and they in turn produce megaspores by meiosis which develop into female gametophytes and these give rise to egg cells. The gynoecium of a flower is described using an alternative terminology wherein the structure one sees in the innermost whorl is called a pistil. A pistil may consist of a carpel or a number of carpels fused together. The sticky tip of the pistil, the stigma, is the receptor of pollen, the supportive stalk, the style, becomes the pathway for pollen tubes to grow from pollen grains adhering to the stigma. The relationship to the gynoecium on the receptacle is described as hypogynous, perigynous, although the arrangement described above is considered typical, plant species show a wide variation in floral structure. These modifications have significance in the evolution of flowering plants and are used extensively by botanists to establish relationships among plant species, the four main parts of a flower are generally defined by their positions on the receptacle and not by their function. Many flowers lack some parts or parts may be modified into other functions and/or look like what is typically another part, in some families, like Ranunculaceae, the petals are greatly reduced and in many species the sepals are colorful and petal-like. Other flowers have modified stamens that are petal-like, the flowers of Peonies and Roses are mostly petaloid stamens
29.
Clade
–
A clade is a group of organisms that consists of a common ancestor and all its lineal descendants, and represents a single branch on the tree of life. The common ancestor may be an individual, a population, a species, clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently, over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades, the term clade was coined in 1957 by the biologist Julian Huxley to refer to the result of cladogenesis, a concept Huxley borrowed from Bernhard Rensch. Many commonly named groups are clades, for example, rodents or insects, because in each case, their name refers to a common ancestor with all its descendant branches. Rodents, for example, are a branch of mammals that split off after the end of the period when the clade Dinosauria stopped being the dominant terrestrial vertebrates 66 million years ago, the original population and all its descendants are a clade. The rodent clade corresponds to the order Rodentia, and insects to the class Insecta and these clades include smaller clades, such as chipmunk or ant, each of which consists of even smaller clades. The clade rodent is in included in the mammal, vertebrate. The phenomenon of convergent evolution is, however, responsible for cases where there are misleading similarities in the morphology of groups that evolved from different lineages. The publication of Darwins theory of evolution in 1859 gave this view increasing weight, thomas Henry Huxley, an early advocate of evolutionary theory, proposed a revised taxonomy based on clades. For example, he grouped birds with reptiles, based on fossil evidence, german biologist Emil Hans Willi Hennig is considered to be the founder of cladistics. Taxonomists have increasingly worked to make the taxonomic system reflect evolution, when it comes to naming, however, this principle is not always compatible with the traditional rank-based nomenclature. For these and other reasons, phylogenetic nomenclature has been developed, a clade is by definition monophyletic, meaning that it contains one ancestor and all its descendants. The ancestor can be known or unknown, any and all members of a clade can be extant or extinct, the science that tries to reconstruct phylogenetic trees and thus discover clades is called phylogenetics or cladistics, the latter term coined by Ernst Mayr, derived from clade. The results of analyses are tree-shaped diagrams called cladograms, they. Three methods of defining clades are featured in phylogenetic nomenclature, node-, stem-, the relationship between clades can be described in several ways, A clade located within a clade is said to be nested within that clade. In the diagram, the clade, i. e. the apes. Two clades are sisters if they have a common ancestor
30.
Basal angiosperms
–
The basal angiosperms are the flowering plants which diverged from the lineage leading to most flowering plants. In particular, the most basal angiosperms were called the ANITA grade which is made up of Amborella, ANITA stands for Amborella, Nymphaeales and Illiciales, Trimeniaceae-Austrobaileya. The basal angiosperms are only a few hundred species, compared with hundreds of thousands of species of eudicots, monocots or magnoliids and they diverged from the ancestral angiosperm lineage before the five groups comprising the mesangiosperms diverged from each other. The exact relationships between Amborella, Nymphaeales and Austrobaileyales are not yet clear, a 2014 paper says that it presents the most convincing evidence to date that Amborella plus Nymphaeales together represent the earliest diverging lineage of extant angiosperms. Paleodicots is a name used by botanists to refer to angiosperms which are not monocots or eudicots. The paleodicots correspond to Magnoliidae sensu Cronquist 1981 and to Magnoliidae sensu Takhtajan 1980, some of the paleodicots share apparently plesiomorphic characters with monocots, e. g. scattered vascular bundles, trimerous flowers, and non-tricolpate pollen. The paleodicots are not a group and the term has not been widely adopted. Subsequent research has added Hydatellaceae to the paleodicots, the term paleoherb is another older term for flowering plants which are neither eudicots nor monocots
31.
Cabombaceae
–
The Cabombaceae are a family of aquatic, herbaceous flowering plants. The family is recognised as distinct in the Angiosperm Phylogeny Group III system, the family consists of two genera of aquatic plants, Brasenia and Cabomba, totalling six species. The Cabombaceae are all aquatic, living in still or slow-moving waters of temperate and tropical North and South America, Europe, Asia, Africa, although found on all continents but Antarctica, the plants tend to grow in relatively restricted ranges. The family has a fossil record from the Cretaceous with plants that exhibit affinities to either the Cabombaceae or Nymphaceae occurring in the Early Cretaceous. One such likely Cretaceous member is the genus Pluricarpellatia, found in rocks 115 million years old in what is now Brazil, the APG system of 1998 included this family in the water lily family Nymphaeaceae, as did the APG II system, of 2003. The APG III system of classification separated the family Cabombaceae from the family Nymphaceae, the family is part of the order Nymphaeales, which is one of the most basal flowering plant lineages. Reconstructing the age and historical biogeography of the ancient flowering-plant family Hydatellaceae, Hydatellaceae identified as a new branch near the base of the angiosperm phylogenetic tree. Cabombaceae in L. Watson and M. J. Dallwitz, the families of flowering plants, descriptions, illustrations, identification, information retrieval
32.
Pollination syndrome
–
These traits include flower shape, size, colour, odour, reward type and amount, nectar composition, timing of flowering, etc. For example, tubular red flowers with copious nectar often attract birds, foul smelling flowers attract carrion flies or beetles, the classical pollination syndromes as they are currently defined were developed in the 19th century by the Italian botanist Federico Delpino. These do not attract animal pollinators, nevertheless, they often have suites of shared traits. Flowers may be small and inconspicuous, as well as green and they produce enormous numbers of relatively small pollen grains. Their stigmas may be large and feathery to catch the pollen grains, anemophilous, or wind pollinated flowers, are usually small and inconspicuous, and do not possess a scent or produce nectar. The anthers may produce a number of pollen grains, while the stamens are generally long. Water-pollinated plants are aquatic and pollen is released into the water, water currents therefore act as a pollen vector in a similar way to wind currents. Their flowers tend to be small and inconspicuous with lots of pollen grains and large, however, this is relatively uncommon and most aquatic plants are insect-pollinated, with flowers that emerge into the air. Bee-pollinated flowers can be variable in their size, shape. They can be open and bowl-shaped or more complex and non-radially symmetric, as is the case with many peas, some bee flowers tend to be yellow or blue, often with ultraviolet nectar guides and scent. Nectar, pollen, or both are offered as rewards in varying amounts, the sugar in the nectar tends to be sucrose-dominated. A few bees collect oil from special glands on the flower, there are diverse types of bees, forming large groups that are quite distinctive in size, tongue length and behaviour, thus generalization about bees is difficult. Some plants can only be pollinated by bees because their anthers release pollen internally, bees are the only animals that perform this behaviour. Bumblebees sonicate, but honeybees do not, wasps are also responsible for the pollination of several plants species, being important pollen vectors, and in some cases, even more efficient pollinators than bees. Butterfly-pollinated flowers tend to be large and showy, pink or lavender in colour, frequently have a landing area, since butterflies do not digest pollen, more nectar is offered than pollen. The flowers have simple nectar guides with the usually hidden in narrow tubes or spurs. Among the more important moth pollinators are the hawk moths and their behaviour is similar to hummingbirds, they hover in front of flowers with rapid wingbeats. So moth-pollinated flowers tend to be white, night-opening, large and showy with tubular corollas, a lot of nectar is produced to fuel the high metabolic rates needed to power their flight
33.
Anemophily
–
Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Almost all gymnosperms are anemophilous, as are plants in the order Poales. Other common anemophilous plants are oaks, sweet chestnuts, alders and members of the family Juglandaceae, features of the wind-pollination syndrome include a lack of scent production, a lack of showy floral parts, reduced production of nectar, and the production of enormous numbers of pollen grains. This distinguishes them from entomophilous and zoophilous species, anemophilous pollen grains are light and non-sticky, so that they can be transported by air currents. They are typically 20–60 micrometres in diameter, although the pollen grains of Pinus species can be much larger, anemophilous plants possess well-exposed stamens so that the pollens are exposed to wind currents and also have large and feathery stigma to easily trap airborne pollen grains. Pollen from anemophilous plants tends to be smaller and lighter than pollen from entomophilous ones, however, insects sometimes gather pollen from staminate anemophilous flowers at times when higher-protein pollens from entomophilous flowers are scarce. Anemophilous pollens may also be captured by bees electrostatic field. This may explain why, though bees are not observed to visit ragweed flowers, anemophily is an adaptation that helps to separate the male and female reproductive systems of a single plant, reducing the effects of inbreeding. It often accompanies dioecy – the presence of male and female structures on separate plants. Almost all pollens that are allergens are from anemophilous species, grasses are the most important producers of aeroallergens in most temperate regions, with lowland or meadow species producing more pollen than upland or moorland species. Media related to Wind pollination at Wikimedia Commons
34.
Sclereid
–
Sclereids are a reduced form of sclerenchyma cells with highly thickened, lignified cellular walls that form small bundles of durable layers of tissue in most plants. The presence of numerous sclereids form the cores of apples and produce the gritty texture of pears, although sclereids are variable in shape, the cells are generally isodiametric, prosenchymatic, forked or elaborately branched. They can be grouped into bundles, can form complete tubes located at the periphery or can occur as single cells or small groups of cells within parenchyma tissues, when compared with most fibres, sclereids are relatively short. Characteristic examples are brachysclereids or the cells of pears and quinces. The cell walls fill nearly all the cells volume, a layering of the walls and the existence of branched pits is clearly visible. Branched pits such as these are called ramiform pits, the shell of many seeds like those of nuts as well as the stones of drupes like cherries or plums are made up from sclereids. These structures are used to other cells. Mauseth, James D. Botany, An Introduction to Plant Biology, sudbury, MA, Jones and Bartlett Learning. Moore, Randy, Clark, W. Dennis, and Vodopich, Darrell S. Botany
35.
Mucilage
–
Mucilage is a thick, gluey substance produced by nearly all plants and some microorganisms. It is a glycoprotein and an exopolysaccharide. Mucilage in plants plays a role in the storage of water and food, seed germination, cacti and flax seeds especially are rich sources of mucilage. Exopolysaccharides are the most stabilising factor for microaggregates and are distributed in soils. Therefore, exopolysaccharide-producing soil algae play a role in the ecology of the worlds soils. The substance covers the outside of, for example, unicellular or filamentous green algae, amongst the green algae especially, the group Volvocales are known to produce exopolysaccharides at a certain point in their life cycle. It occurs in almost all plants, but usually in small amounts and it is frequently associated with substances like tannins and alkaloids. Mucilage has a purpose in some carnivorous plants. The plant genera Drosera, Pinguicula, and others have leaves studded with mucilage-secreting glands and it is used in medicine as it relieves irritation of mucous membranes by forming a protective film. Traditionally, marshmallows were made from the extract of the root of the marshmallow plant as a cough medicine. The inner bark of the elm, a North American tree species, has long been used as a demulcent and is still produced commercially for that purpose. Mucilage mixed with water has been used as a glue, especially for bonding paper items such as labels, postage stamps, and envelope flaps. Differing types and varying strengths of mucilage can also be used for other applications, including gluing labels to metal cans, wood to china. During the fermentation of nattō soybeans, extracellular enzymes produced by the bacterium Bacillus natto react with sugars to produce mucilage. The amount and viscosity of the mucilage are important nattō characteristics, contributing to nattōs unique taste, the mucilage of two kinds of insectivorous plants, sundew and butterwort, is used for the traditional production of a variant of the yoghurt-like Swedish dairy product called filmjölk
36.
Glossary of leaf morphology
–
The following is a defined list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple or compound, the edge of the leaf may be regular or irregular, may be smooth or bearing hair, bristles or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article, leaves of most plants include a flat structure called the blade or lamina, but not all leaves are flat, some are cylindrical. Leaves may be simple, with a leaf blade, or compound. In flowering plants, as well as the blade of the leaf, there may be a petiole and stipules, leaf structure is described by several terms that include, Being one of the more visible features, leaf shape is commonly used for plant identification. Edge and margin are both interchangeable in the sense that they refer to the perimeter of a leaf. Leaves may also be folded or rolled in various ways, the folding of leaves within a bud is vernation, ptyxis is the folding of an individual leaf in a bud
37.
Petiole (botany)
–
In botany, the petiole is the stalk that attaches the leaf blade to the stem. The petiole is the transition between the stem and the leaf blade, outgrowths appearing on each side of the petiole in some species are called stipules. Leaves lacking a petiole are called sessile or epetiolate, the petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves, the stalk may be long, as in the leaves of celery and rhubarb, short or completely absent. Subpetiolate leaves are petiolate, or have an extremely short petiole. The broomrape family Orobanchaceae is an example of a family in which the leaves are always sessile, in some other plant groups, such as the speedwell genus Veronica, petiolate and sessile leaves may occur in different species. In the grasses the leaves are apetiolate, but the blade may be narrowed at the junction with the leaf sheath to form a pseudopetiole. In plants with leaves, the leaflets are attached to a continuation of the petiole called the rachis. Each leaflet may be attached to the rachis by a stalk called the petiolule. There may be swollen regions at either end of the known as pulvina that are composed of a flexible tissue that allows leaf movement. Pulvina are common in the bean family Fabaceae and the plant family Marantaceae. A pulvinus on a petiolule is called a pulvinulus, in some plants, the petioles are flattened and widened, to become phyllodes or phyllodia, or cladophylls and the true leaves may be reduced or absent. Thus, the comes to serve the functions of the leaf. Phyllodes are common in the genus Acacia, especially the Australian species, in Acacia koa, the phyllodes are leathery and thick, allowing the tree to survive stressful environments. The petiole allows partially submerged hydrophytes to have leaves floating at different depths, in plants such as rhubarb, celery, artichokes and cardoons the petioles are cultivated as edible crops. The petiole of rhubarb grows directly from the rhizome and produces the leaf at its end, botanically it is categorized as a vegetable and culinarily used as a fruit. Petiole is pronounced /ˈpiːtᵻoʊl/ and comes from Latin petiolus, or peciolus little foot, stem, the regular diminutive pediculus is also used for foot stalk
38.
Stipule
–
In botany, stipule is a term coined by Linnaeus which refers to outgrowths borne on either side of the base of a leafstalk. A pair of stipules is considered part of the anatomy of the leaf of a flowering plant. In some older botanical writing, the term stipule was used generally to refer to any small leaves or leaf-parts. The position of stipules on a plant varies widely from species to species, stipules are most common on dicotyledons, where they appear in pairs alongside each leaf. Some monocotyledon plants display stipule-like structures, but only one per leaf. A relationship exists between the anatomy of the node and the presence or absence of stipules, most plants with trilacunar nodes have stipules, species with unilacunar nodes lack stipules. Stipules are morphologically variable and might appear as glands, scales, hairs, spines, if a single stipule goes all the way around the stem, it is known as an ochrea. The three types of stipules according to duration are caducous, deciduous and persistent, caducous stipules fall off before the leaf unfolds, while deciduous stipules fall off immediately after the leaf unfolds. Persistent stipules remain attached to the plant, stipules can be considered free lateral, adnate, interpetiolar, intrapetiolar, ochreate, foliaceous, bud scales, tendrillar or spiny. A stipule can be fused to the stem, or to the other stipule from the same node, a stipule is adnate if its fused together on part of the petiole length, but the anterior is still free. A stipule is intrapetiolar if it is located in the angle thats between a stem and a petiole, in this case, the two stipules generally form together and appear to be one stipule. A stipule is ochreate if a single stipule appears to be a tube that goes all the way around the stem. A stipule is foliaceous if it is leaf-like and these are generally used to photosynthesize. A stipule is considered a bud scale if it is hard or scaly and these generally fall off as soon as the leaf unfolds. A stipule is considered tendrillar if they are long thin tendrils, a stipule is considered spiny if they are long and pointy. These are generally used to deter animals, a stipule is considered to be abaxial, counter or leaf opposed if its located on the opposite side to where the leaf meets the stem. Stipules can be used by the plants in various ways, and it is known that foliaceous stipules are used like leaves to make energy for the plants. Sometimes stipules protect the next leaf or bud as it grows in, then falls off after the leaf unfolds, stipules can be used as climbing tendrils by climbing plants
39.
Receptacle (botany)
–
In botany, the receptacle or torus is the thickened part of a stem from which the flower organs grow. In some accessory fruits, for example the pome and strawberry, the fruit of Rubus species is a cluster of drupelets on top of a conical receptacle. When a raspberry is picked, the receptacle separates from the fruit, in phycology, receptacles are structures at the ends of branches of algae mainly in the brown algae or Heterokontophyta in the Order Fucales. They are specialised structures which contain the reproductive organs called conceptacles, receptacles also function as a structure that captures food
40.
Sepal
–
A sepal is a part of the flower of angiosperms. Usually green, sepals typically function as protection for the flower in bud, the term sepalum was coined by Noël Martin Joseph de Necker in 1790, and derived from the Greek σκεπη, a covering. Collectively the sepals are called the calyx, the outermost whorl of parts that form a flower, the word calyx was adopted from the Latin calyx, not to be confused with calix, a cup or goblet. Calyx derived from the Greek κάλυξ, a bud, a calyx, a husk or wrapping, while derived from the Greek κυλιξ, a cup or goblet. After flowering, most plants have no use for the calyx which withers or becomes vestigial. Some plants retain a thorny calyx, either dried or live, examples include species of Acaena, some of the Solanaceae, and the water caltrop, Trapa natans. In some species the calyx not only persists after flowering, but instead of withering and this is an effective protection against some kinds of birds and insects, for example in Hibiscus trionum and the Cape gooseberry. Morphologically, both sepals and petals are modified leaves, the calyx and the corolla are the outer sterile whorls of the flower, which together form what is known as the perianth. The term tepal is usually applied when the parts of the perianth are difficult to distinguish, e. g. the petals and sepals share the same color, or the petals are absent and the sepals are colorful. When the undifferentiated tepals resemble petals, they are referred to as petaloid, as in petaloid monocots, since they include Liliales, an alternative name is lilioid monocots. Examples of plants in which the term tepal is appropriate include genera such as Aloe, in contrast, genera such as Rosa and Phaseolus have well-distinguished sepals and petals. The number of sepals in a flower is its merosity, flower merosity is indicative of a plants classification. The merosity of a flower is typically four or five. The merosity of a monocot or palaeodicot flower is three, or a multiple of three, the development and form of the sepals vary considerably among flowering plants. They may be free or fused together, often, the sepals are much reduced, appearing somewhat awn-like, or as scales, teeth, or ridges. Most often such structures protrude until the fruit is mature and falls off, examples of flowers with much reduced perianths are found among the grasses. In some flowers, the sepals are fused towards the base, in other flowers a hypanthium includes the bases of sepals, petals, and the attachment points of the stamens
41.
Connation
–
Connation in plants is the developmental fusion of organs of the same type, for example, petals to one another to form a tubular corolla. This is in contrast to adnation, the fusion of dissimilar organs, such organs are described as connate or adnate, respectively. When like organs that are well separated are placed next to each other. Synsepalous, All the sepals of a flower are fused into a cup or tube, sympetalous, All the petals of a flower are fused into a cup, tube, or other shape. An apopetalous corolla has free, unfused petals
42.
Stamen
–
The stamen is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium, a stamen typically consists of a stalk called the filament and an anther which contains microsporangia. Most commonly anthers are two-lobed and are attached to the filament either at the base or in the area of the anther. The sterile tissue between the lobes is called the connective, a pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The stamens in a flower are called the androecium. The androecium can consist of as few a one-half stamen as in Canna species or as many as 3,482 stamens which have been counted in Carnegiea gigantea, the androecium in various species of plants forms a great variety of patterns, some of them highly complex. It surrounds the gynoecium and is surrounded by the perianth, a few members of the family Triuridaceae, particularly Lacandonia schismatica, are exceptional in that their gynoecia surround their androecia. Stamen is the Latin word meaning thread, depending on the species of plant, some or all of the stamens in a flower may be attached to the petals or to the floral axis. They also may be free-standing or fused to one another in different ways, including fusion of some. The filaments may be fused and the free, or the filaments free. Rather than there being two locules, one locule of a stamen may fail to develop, or alternatively the two locules may merge late in development to give a single locule, a typical anther contains four microsporangia. The microsporangia form sacs or pockets in the anther, the two separate locules on each side of an anther may fuse into a single locule. Each microsporangium is lined with a tissue layer called the tapetum. These undergo meiosis to form haploid spores, the spores may remain attached to each other in a tetrad or separate after meiosis. Each microspore then divides mitotically to form an immature microgametophyte called a pollen grain, the pollen is eventually released when the anther forms openings. These may consist of longitudinal slits, pores, as in the family, or by valves. More commonly, mature pollen grains separate and are dispensed by wind or water, pollinating insects, pollen of angiosperms must be transported to the stigma, the receptive surface of the carpel, of a compatible flower, for successful pollination to occur. After arriving, the pollen grain typically completes its development and it may grow a pollen tube and undergoing mitosis to produce two sperm nuclei