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Eichhornia Crassipes
''Pontederia crassipes'' (formerly ''Eichhornia crassipes''), commonly known as common water hyacinth is an aquatic plant native to South America, naturalized throughout the world, and often invasive outside its native range.''Pontederia crassipes'' Kew Royal Botanic Gardens Plants of the World Online. Accessed April 19, 2022.''Eichhornia crassipes'' Kew Royal Botanic Gardens Plants of the World Online. Accessed April 19, 2022. June 15, 2016. Flora of Banglade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eichhornia
''Eichhornia'', commonly called water hyacinths, was a polyphyletic genus of the aquatic flowering plants family Pontederiaceae. Since it was consistently recovered in three independent lineages, it has been sunk into '' Pontederia'', together with ''Monochoria''. Each of the three lineages is currently recognized as subgenera in ''Pontederia'': * ''Pontederia'' subg. ''Cabanisia'', which includes '' P. meyeri'', '' P. paniculata'' (the Brazilian water hyacinth), and '' P. paradoxa'' * ''Pontederia'' subg. ''Oshunae'', which includes the common water hyacinth, '' P. crassipes'' * ''Pontederia'' subg. ''Eichhornia'', which includes '' P. azurea'', '' P. diversifolia'', '' P. heterosperma'', and '' P. natans'' ''Pontederia'' subg. ''Eichhornia'' is pantropical, centered in South America but with '' P. natans'' being endemic to continental Africa and Madagascar. The other three species are restricted to the Neotropics. It was named in honour of , an early-19th-century Prussian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropics
The subtropical zones or subtropics are geographical and climate zones to the north and south of the tropics. Geographically part of the temperate zones of both hemispheres, they cover the middle latitudes from to approximately 35° north and south. The horse latitudes lie within this range. Subtropical climates are often characterized by hot summers and mild winters with infrequent frost. Most subtropical climates fall into two basic types: humid subtropical ( Koppen climate Cfa), where rainfall is often concentrated in the warmest months, for example Southeast China and the Southeastern United States, and dry summer or Mediterranean climate ( Koppen climate Csa/Csb), where seasonal rainfall is concentrated in the cooler months, such as the Mediterranean Basin or Southern California. Subtropical climates can also occur at high elevations within the tropics, such as in the southern end of the Mexican Plateau and in Da Lat of the Vietnamese Central Highlands. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itch
Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response patterns are different. Pain creates a withdrawal reflex, whereas itch leads to a scratch reflex. Unmyelinated nerve fibers for itch and pain both originate in the skin; however, information for them is conveyed centrally in two distinct systems that both use the same nerve bundle and spinothalamic tract. Classification Most commonly, an itch is felt in one place. If it is felt all over the body, then it is called ''generalized itch'' or ''generalized pruritus''. If the sensation of itching persists for six weeks or longer, then it is called ''chronic itch'' or ''chronic pruritus''. ''Chronic idiopathic pruritus'' or ''essential pruritus'' is a rare form of itch that persists for longer t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpenoid
The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes", terpenoids contain additional functional groups, usually containing oxygen. When combined with the hydrocarbon terpenes, terpenoids comprise about 80,000 compounds. They are the largest class of plant secondary metabolites, representing about 60% of known natural products. Many terpenoids have substantial pharmacological bioactivity and are therefore of interest to medicinal chemists. Plant terpenoids are used for their aromatic qualities and play a role in traditional herbal remedies. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes. Well-known terpenoids include citral, menthol, camphor, salvinorin A in the plant ''Salvia div ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen, sulfur and, more rarely, other elements such as chlorine, bromine, and phosphorus.Chemical Encyclopedia: alkaloids xumuk.ru Alkaloids are produced by a large variety of organisms including , , |
Hydrogen Cyanide
Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging from polymers to pharmaceuticals. Large-scale applications are for the production of potassium cyanide and adiponitrile, used in mining and plastics, respectively. It is more toxic than solid cyanide compounds due to its volatile nature. Structure and general properties Hydrogen cyanide is a linear molecule, with a triple bond between carbon and nitrogen. The tautomer of HCN is HNC, hydrogen isocyanide. Hydrogen cyanide is weakly acidic with a p''K''a of 9.2. It partially ionizes in water solution to give the cyanide anion, CN−. A solution of hydrogen cyanide in water, represented as HCN, is called ''hydrocyanic acid''. The salts of the cyanid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word ''crystal'' derives from the Ancient Greek word (), meaning both "ice" and "rock crystal", from (), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Polycrystals include most metals, rocks, ceramics, and ice. A third category ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colorless and odorless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element. Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids ( DNA and RNA) and in the energy transfer molecule adenosine triphosphate. The human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. The nitrogen cycle describes the movement of the element from the air, into the biosphere and organic compounds, then back into the atmosphere. Many indus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petiole (botany)
In botany, the petiole () is the stalk that attaches the leaf blade to the stem, and is able to twist the leaf to face the sun. This gives a characteristic foliage arrangement to the plant. Outgrowths appearing on each side of the petiole in some species are called stipules. Leaves with a petiole are said to be petiolate, while leaves lacking a petiole are called sessile or apetiolate. Description The petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves, the leaf stalk may be long, as in the leaves of celery and rhubarb, or short. When completely absent, the blade attaches directly to the stem and is said to be sessile. Subpetiolate leaves have an extremely short petiole, and may appear sessile. 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 ( Poaceae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azotobacter Chroococcum
''Azotobacter chroococcum'' is a bacterium that has the ability to fix atmospheric nitrogen. It was discovered by Martinus Beijerinck in 1901, and was the first aerobic, free-living nitrogen fixer discovered. ''A. chroococcum'' could be useful for nitrogen fixation in crops as a biofertilizer, fungicide, and nutrient indicator, and in bioremediation. Characteristics ''A. chroococcum'' is a microaerophilic plant growth-promoting rhizobacterium (PGRP), which is bacillus in shape and is Gram negative. As a mesophile, this bacterium grows best in moderate-temperature soils and requires a neutral pH environment. It is able to fix nitrogen under aerobic conditions. The soil cannot be poor in phosphorus or else nitrogen fixing can be hindered. In addition to phosphorus, these bacteria needed potassium, "sulphur, magnesium, and calcium" to grow. To fix nitrogen ''A. chroococcum'' produces three enzymes ( catalase, peroxidase, and superoxide dismutase) to "neutralise" reactive oxygen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorosis
In botany, chlorosis is a condition in which leaves produce insufficient chlorophyll. As chlorophyll is responsible for the green color of leaves, chlorotic leaves are pale, yellow, or yellow-white. The affected plant has little or no ability to manufacture carbohydrates through photosynthesis and may die unless the cause of its chlorophyll insufficiency is treated and this may lead to a plant diseases called rusts, although some chlorotic plants, such as the albino ''Arabidopsis thaliana'' mutant ''ppi2'', are viable if supplied with exogenous sucrose. The word ''chlorosis'' is derived from the Greek ''khloros'' meaning "greenish-yellow", "pale green", "pale", "pallid", or "fresh". In viticulture, the most common symptom of poor nutrition in grapevines is the yellowing of grape leaves caused by chlorosis and the subsequent loss of chlorophyll. This is often seen in vineyard soils that are high in limestone such as the Italian wine region of Barolo in the Piedmont, the Spanish w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
