Johann Hedwig
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Johann Hedwig
Johann Hedwig (8 December 1730 – 18 February 1799), also styled as Johannes Hedwig, was a German botanist notable for his studies of mosses. He is sometimes called the "father of bryology". He is known for his particular observations of sexual reproduction in the cryptogams. Many of his writings were in Latin, and his name is rendered in Latin as Ioannis Hedwig or Ioanne Hedwig. Early life Hedwig was born in Brașov, Transylvania, on 8 December 1730. As the son of a shoemaker, he grew up in poverty. It was in his childhood he became fascinated with mosses.Isely, Duane. One Hundred and One Botanists. Purdue University Press, 2002. He went on to study medicine at the University of Leipzig, and received his medical degree in 1759. Career After receiving his degree, Hedwig worked as a physician for the next twenty years. When he was not granted a license to practice in Transylvania with his Leipzig degree, he worked as a general practitioner in Chemnitz. It was during this tim ...
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Principality Of Transylvania (1711–1867)
The Principality of Transylvania, from 1765 the Grand Principality of Transylvania, was a realm of the Hungarian Crown and from 1804 an Austrian crownlandChambers's Encyclopaedia Vol. IX
1860, Chambers's Encyclopaedia based on , 10th Edition
ruled by the and

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Biological Illustration
Biological illustration is the use of technical illustration to visually communicate the structure and specific details of biological subjects of study. This can be used to demonstrate anatomy, explain biological functions or interactions, direct surgical procedures, distinguish species, and other applications. The scope of biological illustration can range from the whole organism level to microscopic. Subcategories Types of biological illustrations include: *Medical illustration *Botanical illustration * Zoological illustration History Historically, biological illustrations have been in use since the beginning of man's exploration and attempts to understand the world around him. The paleolithic cave paintings were so detailed that we can even recognize species and breeds of many of the depicted animals today. For example, in the Chauvet-Pont-d'Arc Cave (circa 30,000 BC), at least 13 different species have been identified. In one prehistoric cave (circa 15,000 BC), there is a dra ...
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Academy Of Sciences Leopoldina
The German National Academy of Sciences Leopoldina (german: Deutsche Akademie der Naturforscher Leopoldina – Nationale Akademie der Wissenschaften), short Leopoldina, is the national academy of Germany, and is located in Halle (Saale). Founded on January 1, 1652, based on academic models in Italy, it was originally named the ''Academia Naturae Curiosorum'' until 1687 when Emperor Leopold I raised it to an academy and named it after himself. It was since known under the German name ''Deutsche Akademie der Naturforscher Leopoldina'' until 2007, when it was declared to be Germany's National Academy of Sciences. History ' The Leopoldina was founded in the imperial city of Schweinfurt on 1 January 1652 under the Latin name sometimes translated into English as "Academy of the Curious as to Nature." It was founded by four local physicians- Johann Laurentius Bausch, the first president of the society, Johann Michael Fehr, Georg Balthasar Metzger, and Georg Balthasar Wohlfarth; and ...
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Royal Swedish Academy Of Sciences
The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) is one of the royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting natural sciences and mathematics and strengthening their influence in society, whilst endeavouring to promote the exchange of ideas between various disciplines. The goals of the academy are: * to be a forum where researchers meet across subject boundaries, * to offer a unique environment for research, * to provide support to younger researchers, * to reward outstanding research efforts, * to communicate internationally among scientists, * to advance the case for science within society and to influence research policy priorities * to stimulate interest in mathematics and science in school, and * to disseminate and popularize scientific information in various forms. Every year, the academy awards the Nobel Prizes in physics and chemis ...
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Fellow Of The Royal Society
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathematics, engineering science, and medical science". Fellowship of the Society, the oldest known scientific academy in continuous existence, is a significant honour. It has been awarded to many eminent scientists throughout history, including Isaac Newton (1672), Michael Faraday (1824), Charles Darwin (1839), Ernest Rutherford (1903), Srinivasa Ramanujan (1918), Albert Einstein (1921), Paul Dirac (1930), Winston Churchill (1941), Subrahmanyan Chandrasekhar (1944), Dorothy Hodgkin (1947), Alan Turing (1951), Lise Meitner (1955) and Francis Crick (1959). More recently, fellowship has been awarded to Stephen Hawking (1974), David Attenborough (1983), Tim Hunt (1991), Elizabeth Blackburn (1992), Tim Berners-Lee (2001), Venki Ramakrishn ...
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David Meese
Cover of the ''Flora frisica'' David Meese (25 December 1723 – 23 August 1770) was a Dutch botanist notable for his authorship of the ''Flora frisica'' in 1760. Career Born into a low class family, Meese became a self taught herbalist. His skills were recognized by the University of Franeker where he was placed in charge of the academic gardens at the college in 1752. Aa, A. J. (1859). Biographisch woordenboek der Nederlanden (Deel. 12-1). Retrieved from http://resources.huygens.knaw.nl/retroboeken/vdaa/#source=aa__001biog14_01.xml&page=523&view=imagePane&accessor=accessor_index&accessor_href=http://resources.huygens.knaw.nl/retroboeken/vdaa/accessor_index/index_html?page=523&source=aa__001biog14_01.xml&id=accessor_index In 1760, Meese published a flora of Friesland, the ''Flora frisica'', which followed the Linnaean system of classification. He followed this with the publication of the two-part ''Plantarum rudimenta etc.'' in 1763, written in both Latin and Dutch.Molhuysen ...
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Spirogyra
''Spirogyra'' (common names include water silk, mermaid's tresses, and blanket weed) is a genus of filamentous charophyte green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is characteristic of the genus. ''Spirogyra'' species, of which there are more than 400, are commonly found in freshwater habitats. ''Spirogyra'' measures approximately 10 to 100 μm in width and may grow to several centimetres in length. It is often observed as green slimy patches on the ground near ponds and other water bodies having stagnant water. General characteristics ''Spirogyra'' is very common in relatively clear eutrophic water, developing slimy filamentous green masses. In spring ''Spirogyra'' grows under water, but when there is enough sunlight and warmth they produce large amounts of oxygen, adhering as bubbles between the tangled filaments. The filamentous masses come to the surface and become visible as slimy green mats. ''Spirog ...
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Chara (alga)
''Chara'' is a genus of charophyte green algae in the family Characeae. They are multicellular and superficially resemble land plants because of stem-like and leaf-like structures. They are found in freshwater, particularly in limestone areas throughout the northern temperate zone, where they grow submerged, attached to the muddy bottom. They prefer less oxygenated and hard water and are not found in waters where mosquito larvae are present. They are covered with calcium carbonate deposits and are commonly known as stoneworts. Cyanobacteria have been found growing as epiphytes on the surfaces of ''Chara'', where they may be involved in fixing nitrogen, which is important to plant nutrition. Structure The branching system of ''Chara'' species is complex with branches derived from apical cells which cut off segments at the base to form nodal and internodal cells alternately.Round, F.E. 1965.''The Biology of the algae.'' Ernest Arnold. The main axes bear whorls of branches in ...
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Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around their re ...
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Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ...
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Fern
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except the lycopods, and differ from mosses and other bryophytes by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaves called megaphylls, that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate ( Polypodiidae) and eusporangiate ferns, the latter group including horsetails, whisk ferns, marattioid ferns, and ophioglossoid ...
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Sporophyte
A sporophyte () is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote produced when a haploid egg cell is fertilized by a haploid sperm and each sporophyte cell therefore has a double set of chromosomes, one set from each parent. All land plants, and most multicellular algae, have life cycles in which a multicellular diploid sporophyte phase alternates with a multicellular haploid gametophyte phase. In the seed plants, the largest groups of which are the gymnosperms and flowering plants (angiosperms), the sporophyte phase is more prominent than the gametophyte, and is the familiar green plant with its roots, stem, leaves and cones or flowers. In flowering plants the gametophytes are very reduced in size, and are represented by the germinated pollen and the embryo sac. The sporophyte produces spores (hence ...
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