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Cuttings (plants)
A plant cutting is a piece of a plant that is used in horticulture for vegetative (asexual) propagation. A piece of the stem or root of the source plant is placed in a suitable medium such as moist soil. If the conditions are suitable, the plant piece will begin to grow as a new plant independent of the parent, a process known as striking. A stem cutting produces new roots, and a root cutting produces new stems. Some plants can be grown from leaf pieces, called leaf cuttings, which produce both stems and roots. The scions used in grafting are also called cuttings. Propagating plants from cuttings is an ancient form of cloning. There are several advantages of cuttings, mainly that the produced offspring are practically clones of their parent plants. If a plant has favorable traits, it can continue to pass down its advantageous genetic information to its offspring. This is especially economically advantageous as it allows commercial growers to clone a certain plant to ensure consiste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adventitious Roots Of Magnolia Cutting
Important structures in plant development are buds, shoots, roots, leaf, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant always has embryonic tissues. By contrast, an animal embryo will very early produce all of the body parts that it will ever have in its life. When the animal is born (or hatches from its egg), it has all its body parts and from that point will only grow larger and more mature. However, both plants and animals pass through a phylotypic stage that evolved independently and that causes a developmental constraint limiting morphological diversification. According to plant physiology, plant physiologist A. Carl Leopold, the properties of organization seen in a plant are emergence, emergent properties which are more than the sum of the individual parts. "The assembly of these tissues and functions into an integrated multicellular organism y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jasmonic Acid
Jasmonic acid (JA) is an organic compound found in several plants including jasmine. The molecule is a member of the jasmonate class of plant hormones. It is biosynthesized from linolenic acid by the octadecanoid pathway. It was first isolated in 1957 as the methyl ester of jasmonic acid by the Swiss chemist Edouard Demole and his colleagues. Biosynthesis Its biosynthesis starts from the fatty acid linolenic acid, which is oxygenated by lipoxygenase (13-LOX), forming a hydroperoxide. This peroxide then cyclizes in the presence of allene oxide synthase to form an allene oxide. The rearrangement of allene oxide to form 12-oxophytodienoic acid is catalyzed by the enzyme allene oxide cyclase. A series of β-oxidations result in 7-iso-jasmonic acid. In the absence of enzyme, this iso-jasmonic acid isomerizes to jasmonic acid. Function The major function of JA and its various metabolites is regulating plant responses to abiotic and biotic stresses as well as plant growth and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermiculite
Vermiculite is a hydrous phyllosilicate mineral which undergoes significant expansion when heated. Exfoliation occurs when the mineral is heated sufficiently, and commercial furnaces can routinely produce this effect. Vermiculite forms by the weathering or hydrothermal alteration of biotite or phlogopite. http://www.mindat.org/min-4170.html Mindat.org Large commercial vermiculite mines currently exist in the United States, Russia, South Africa, China, and Brazil. Occurrence Vermiculite was first described in 1824 for an occurrence in Millbury, Massachusetts. Its name is from Latin , "to breed worms", for the manner in which it exfoliates when heated. It typically occurs as an alteration product at the contact between felsic and mafic or ultramafic rocks such as pyroxenites and dunites. It also occurs in carbonatites and metamorphosed magnesium-rich limestone. Associated mineral phases include: corundum, apatite, serpentine, and talc. It occurs interlayered with chlorite, bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perlite
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. It is an industrial mineral, suitable "as ceramic flux to lower the sintering temperature", and a commercial product useful for its low density after processing. Properties Perlite softens when it reaches temperatures of . Water trapped in the structure of the material vaporises and escapes, and this causes the expansion of the material to 7–16 times its original volume. The expanded material is a brilliant white, due to the reflectivity of the trapped bubbles. Unexpanded ("raw") perlite has a bulk density around 1100 kg/m3 (1.1 g/cm3), while typical expanded perlite has a bulk density of about 30–150 kg/m3 (0.03–0.150 g/cm3). Typical analysis *70–75% silicon dioxide: SiO2 *12–15% aluminium oxide: Al2O3 *3–4% sodium oxide: Na2O *3–5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydration
In physiology, dehydration is a lack of total body water, with an accompanying disruption of metabolic processes. It occurs when free water loss exceeds free water intake, usually due to exercise, disease, or high environmental temperature. Mild dehydration can also be caused by immersion diuresis, which may increase risk of decompression sickness in divers. Most people can tolerate a 3-4% decrease in total body water without difficulty or adverse health effects. A 5-8% decrease can cause fatigue and dizziness. Loss of over ten percent of total body water can cause physical and mental deterioration, accompanied by severe thirst. Death occurs at a loss of between fifteen and twenty-five percent of the body water.Ashcroft F, Life Without Water in Life at the Extremes. Berkeley and Los Angeles, 2000, 134-138. Mild dehydration is characterized by thirst and general discomfort and is usually resolved with oral rehydration. Dehydration can cause hypernatremia (high levels of sodium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rooting Of Softwood Cuttings Of Elm Under The Mist Propagation System
Rooting may refer to: * Gaining superuser access to a computer system ** Rooting (Android), attaining root access on Android devices ** Jailbreaking (iOS), overriding iOS software restrictions * Cutting (plant), a plant propagation technique * the rooting reflex Primitive reflexes are reflex actions originating in the central nervous system that are exhibited by normal infants, but not neurologically intact adults, in response to particular stimuli. These reflexes are suppressed by the development of the f ... * the Australian slang for having sexual intercourse {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indole-3-acetic Acid
Indole-3-acetic acid (IAA, 3-IAA) is the most common naturally occurring plant hormone of the auxin class. It is the best known of the auxins, and has been the subject of extensive studies by plant physiologists. IAA is a derivative of indole, containing a carboxymethyl substituent. It is a colorless solid that is soluble in polar organic solvents. Biosynthesis IAA is predominantly produced in cells of the apex (bud) and very young leaves of a plant. Plants can synthesize IAA by several independent biosynthetic pathways. Four of them start from tryptophan, but there is also a biosynthetic pathway independent of tryptophan. Plants mainly produce IAA from tryptophan through indole-3-pyruvic acid. IAA is also produced from tryptophan through indole-3-acetaldoxime in ''Arabidopsis thaliana''. In rats, IAA is a product of both endogenous and colonic microbial metabolism from dietary tryptophan along with tryptophol. This was first observed in rats infected by ''Trypanosoma bruc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambium
A cambium (plural cambia or cambiums), in plants, is a tissue layer that provides partially undifferentiated cells for plant growth. It is found in the area between xylem and phloem. A cambium can also be defined as a cellular plant tissue from which phloem, xylem, or cork grows by division, resulting (in woody plants) in secondary thickening. It forms parallel rows of cells, which result in secondary tissues. There are several distinct kinds of cambium found in plant stems and roots: * Cork cambium, a tissue found in many vascular plants as part of the periderm. * Unifacial cambium, which ultimately produces cells to the interior of its cylinder. * Vascular cambium, a lateral meristem in the vascular tissue of plants. Uses The cambium of many species of woody plants are edible; however, due to its vital role in the homeostasis and growth of woody plants, this may result in death of the plant if enough cambium is removed at once. The cambium can generally be eaten raw or cooke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primordium
A primordium (; plural: primordia; synonym: anlage) in embryology, is an organ or tissue in its earliest recognizable stage of development. Cells of the primordium are called primordial cells. A primordium is the simplest set of cells capable of triggering growth of the would-be organ and the initial foundation from which an organ is able to grow. In flowering plants, a floral primordium gives rise to a flower. Although it is a frequently used term in plant biology, the word is used in describing the biology of all multicellular organisms (for example: a tooth primordium in animals, a leaf primordium in plants or a sporophore primordium in fungi.) Primordium development in plants Plants produce both leaf and flower primordia cells at the shoot apical meristem (SAM). Primordium development in plants is critical to the proper positioning and development of plant organs and cells. The process of primordium development is intricately regulated by a set of genes that affect the pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CGMP-dependent Protein Kinase
cGMP-dependent protein kinase or protein kinase G (PKG) is a serine/threonine-specific protein kinase that is activated by cGMP. It phosphorylates a number of biologically important targets and is implicated in the regulation of smooth muscle relaxation, platelet function, sperm metabolism, cell division, and nucleic acid synthesis. Genes and proteins PKG are serine/threonine kinases that are present in a variety of eukaryotes ranging from the unicellular organism ''Paramecium'' to humans. Two PKG genes, coding for PKG type I (PKG-I) and type II (PKG-II), have been identified in mammals. The N-terminus of PKG-I is encoded by two alternatively spliced exons that specify for the PKG-Iα and PKG-Iβ isoforms. PKG-Iβ is activated at ~10-fold higher cGMP concentrations than PKG-Iα. The PKG-I and PKG-II are homodimers of two identical subunits (~75 kDa and ~85 kDa, respectively) and share common structural features. Each subunit is composed of three functional domains: * ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitogen-activated Protein Kinase
A mitogen-activated protein kinase (MAPK or MAP kinase) is a type of protein kinase that is specific to the amino acids serine and threonine (i.e., a serine/threonine-specific protein kinase). MAPKs are involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock and proinflammatory cytokines. They regulate cell functions including proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis. MAP kinases are found in eukaryotes only, but they are fairly diverse and encountered in all animals, fungi and plants, and even in an array of unicellular eukaryotes. MAPKs belong to the CMGC (CDK/MAPK/GSK3/CLK) kinase group. The closest relatives of MAPKs are the cyclin-dependent kinases (CDKs). Discovery The first mitogen-activated protein kinase to be discovered was ERK1 (MAPK3) in mammals. Since ERK1 and its close relative ERK2 (MAPK1) are both involved in growth factor signaling, the family was term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
