|
Gall Isographic Projection SW
Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or warts in animals. They can be caused by various parasites, from viruses, fungi and bacteria, to other plants, insects and mites. Plant galls can be such highly organized structures that their cause can be determined without the actual agent being identified. This applies particularly to insect and mite plant galls. The study of plant galls is known as cecidology. Anatomy Shape and size Galls develop on various plant organs, providing nutrition and shelter to inducing insects. Galls display vast variation in morphology, size, and wall composition. The size of insect galls can range significantly, from approximately two inches in diameter to less than one-sixteenth of an inch. Some galls are so small that they are merely slightly thickene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andricus Lignicola - Cola-nut Gall
''Andricus'' is a genus of oak gall wasps in the family Cynipidae. Life cycle As in all Hymenoptera, sex-determination in species of the genus ''Andricus'' is governed by haplodiploidy: males develop from unfertilized eggs and are haploid, and females develop from fertilized eggs and are diploid. Many species in the genus alternate between an asexual generation and a sexual generation. Species The taxonomy of the genus ''Andricus'' is uncertain, with many of the approximately 375 species considered dubious. The following species are currently recognised in the genus ''Andricus'': * '' Andricus aciculatus'' Beutenmuller, 1909 * '' Andricus ahmeti'' Melika, Mutun & Dinç, 2014 * '' Andricus albipes'' Hartig, 1840 * '' Andricus albobalani'' Weld, 1926 * '' Andricus alniensis'' Folliot, 1964 * '' Andricus amblycerus'' (Giraud, 1859) * '' Andricus amenti'' Giraud, 1859 * '' Andricus analis'' (Fonscolombe, 1832) * '' Andricus anatolicus'' Melika, Mutun & Dinç, 2014 * '' Andr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osmosis
Osmosis (, ) is the spontaneous net movement or diffusion of solvent molecules through a selectively permeable membrane, selectively-permeable membrane from a region of high water potential (region of lower solute concentration) to a region of low water potential (region of higher solute concentration), in the direction that tends to equalize the solute concentrations on the two sides. It may also be used to describe a physical process in which any solvent moves across a selectively permeable membrane (permeable to the solvent, but not the solute) separating two solutions of different concentrations. Osmosis can be made to do Work (physics), work. Osmotic pressure is defined as the external pressure required to prevent net movement of solvent across the membrane. Osmotic pressure is a colligative properties, colligative property, meaning that the osmotic pressure depends on the molar concentration of the solute but not on its identity. Osmosis is a vital process in biology, bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quercus Rubra
''Quercus rubra'', the northern red oak, is an oak tree in the red oak group (''Quercus'' section ''Lobatae''). It is a native of North America, in the eastern and central United States and southeast and south-central Canada. It has been introduced to small areas in Western Europe, where it can frequently be seen cultivated in gardens and parks. It prefers good soil that is slightly acidic. Often simply called red oak, northern red oak is so named to distinguish it from southern red oak (''Q. falcata''), also known as the Spanish oak. Northern red oak is sometimes called champion oak. Description In many forests, ''Quercus rubra'' grows straight and tall, to , exceptionally to tall, with a trunk of up to in diameter. Open-grown trees do not get as tall, but can develop a stouter trunk, up to in diameter. It has stout branches growing at right angles to the stem, forming a narrow round-topped head. Under optimal conditions and full sun, northern red oak is fast growing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most important of these proteins are the histones. Aided by chaperone proteins, the histones bind to and condense the DNA molecule to maintain its integrity. These eukaryotic chromosomes display a complex three-dimensional structure that has a significant role in transcriptional regulation. Normally, chromosomes are visible under a light microscope only during the metaphase of cell division, where all chromosomes are aligned in the center of the cell in their condensed form. Before this stage occurs, each chromosome is duplicated ( S phase), and the two copies are joined by a centromere—resulting in either an X-shaped structure if the centromere is located equatorially, or a two-armed structure if the centromere is located distally; the jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transfer DNA
The transfer DNA (abbreviated T-DNA) is the transferred DNA of the tumor-inducing (Ti) plasmid of some species of bacteria such as ''Agrobacterium tumefaciens'' and '' Agrobacterium rhizogenes (actually an Ri plasmid)''. The T-DNA is transferred from bacterium into the host plant's nuclear DNA genome. The capability of this specialized tumor-inducing (Ti) plasmid is attributed to two essential regions required for DNA transfer to the host cell. The T-DNA is bordered by 25-base-pair repeats on each end. Transfer is initiated at the right border and terminated at the left border and requires the ''vir'' genes of the Ti plasmid. The bacterial T-DNA is about 24,000 base pairs long and contains plant-expressed genes that code for enzymes synthesizing opines and phytohormones. By transferring the T-DNA into the plant genome, the bacterium essentially reprograms the plant cells to grow into a tumor and produce a unique food source for the bacteria. The synthesis of the plant hormones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invertase
β-Fructofuranosidase is an enzyme that catalyzes the hydrolysis (breakdown) of the table sugar sucrose into fructose and glucose. Sucrose is a fructoside. Alternative names for β-fructofuranosidase include invertase, saccharase, glucosucrase, β-fructosidase, invertin, fructosylinvertase, alkaline invertase, and acid invertase. The resulting mixture of fructose and glucose is called inverted sugar syrup. Related to invertases are sucrases. Invertases and sucrases hydrolyze sucrose to give the same mixture of glucose and fructose. Invertase is a glycoprotein that hydrolyses (cleaves) the non-reducing terminal β-fructofuranoside residues. Invertases cleave the O-C(fructose) bond, whereas the sucrases cleave the O-C(glucose) bond. Invertase cleaves the α-1,2-glycosidic bond of sucrose. For industrial use, invertase is usually derived from yeast. It is also synthesized by bees, which use it to make honey from nectar. The temperature optimum is 60 °C and a pH optimum i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinin
A kinin is any of various structurally related peptides, such as bradykinin and kallidin. They are members of the autacoid family. Kinins are peptides that are cleaved from kininogens by the process of kallikreins. Kallikreins activate kinins when stimulated. It is a component of the kinin-kallikrein system. Their precursors are kininogens. Kininogens contain a 9-11 amino acid bradykinin sequence. In botany, the plant hormones known as cytokinins were first called kinins; the name was changed to avoid confusion. Effects of kinins Kinins are short-lived peptides that cause pain sensation, arteriolar dilation, increase vascular permeability, and cause contractions in smooth muscle. Kinins transmit their effects through G protein-coupled receptors. Kinins act on axons to block nerve impulses, which leads to distal muscle relaxation. They are also potent nerve stimulators which are mostly responsible for the pain sensation (and sometimes itching). Kinins increase vasc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auxin
Auxins (plural of auxin ) are a class of plant hormones (or plant-growth regulators) with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essential for plant body development. The Dutch biologist Frits Warmolt Went first described auxins and their role in plant growth in the 1920s. Kenneth V. Thimann became the first to isolate one of these phytohormones and to determine its chemical structure as indole-3-acetic acid (IAA). Went and Thimann co-authored a book on plant hormones, ''Phytohormones'', in 1937. Overview Auxins were the first of the major plant hormones to be discovered. They derive their name from the Greek word ( – 'to grow/increase'). Auxin is present in all parts of a plant, although in very different concentrations. The concentration in each position is crucial developmental information, so it is subject to tight regulation through both metabolism and transp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Hormone
Plant hormones (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, including embryogenesis, the regulation of Organ (anatomy), organ size, pathogen defense, Stress (biology), stress tolerance and Reproduction, reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Frits Warmolt Went, Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in vascular plant, vascular plants ("higher plants"). Some phytohormones also occur in microorganisms, such as unicellular fungus, fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metaplasia
Metaplasia () is the transformation of a cell type to another cell type. The change from one type of cell to another may be part of a normal maturation process, or caused by some sort of abnormal stimulus. In simplistic terms, it is as if the original cells are not robust enough to withstand their environment, so they transform into another cell type better suited to their environment. If the stimulus causing metaplasia is removed or ceases, tissues return to their normal pattern of differentiation. Metaplasia is not synonymous with dysplasia, and is not considered to be an actual cancer. It is also contrasted with heteroplasia, which is the spontaneous abnormal growth of cytologic and histologic elements. Today, metaplastic changes are usually considered to be an early phase of carcinogenesis, specifically for those with a history of cancers or who are known to be susceptible to carcinogenic changes. Metaplastic change is thus often viewed as a premalignant condition th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenolic Acid
Phenolic acids or phenolcarboxylic acids ? are phenolic compounds and types of aromatic acid compounds. Included in that class are substances containing a phenolic ring and an organic carboxylic acid function (C6-C1 skeleton). Two important naturally occurring types of phenolic acids are hydroxybenzoic acids and hydroxycinnamic acids, which are derived from non-phenolic molecules of benzoic and cinnamic acid, respectively. Occurrences Phenolic acids can be found in many plant species. Their content in dried fruits can be high. Natural phenols in horse grams (''Macrotyloma uniflorum'') are mostly phenolic acids, namely 3,4-dihydroxy benzoic, ''p''-hydroxy benzoic, vanillic, caffeic, ''p''-coumaric, ferulic, syringic, and sinapinic acids. Phenolic acids can be found in several mushroom-forming species of basidiomycetes. It is also a part of the humic substances, which are the major organic constituents of soil humus. Many phenolic acids can be found in human urin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
