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Sporopollenin
270px, SEM image of pollen grains Sporopollenin is a biological polymer found as a major component of the tough outer (exine) walls of plant spores and pollen grains. It is chemically very stable (one of the most inert among biopolymers) and is usually well preserved in soils and sediments. The exine layer is often intricately sculptured in species-specific patterns, allowing material recovered from (for example) lake sediments to provide useful information to palynologists about plant and fungal populations in the past. Sporopollenin has found uses in the field of paleoclimatology as well. Sporopollenin is also found in the cell walls of several taxa of green alga, including '' Phycopeltis'' (an ulvophycean) and '' Chlorella''. Spores are dispersed by many different environmental factors, such as wind, water or animals. In suitable conditions, the sporopollenin-rich walls of pollen grains and spores can persist in the fossil record for hundreds of millions of years, since sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen
Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male Conifer cone, cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it Germination, germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and Forensic science, forensics. Pollen in plants is used for transferring Ploidy#Haploid and monoploid, haploid male genetic ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylpropanoid
The phenylpropanoids are a diverse family of organic compounds that are biosynthesized by plants from the amino acids phenylalanine and tyrosine in the shikimic acid pathway. Their name is derived from the six-carbon, aromatic phenyl group and the three-carbon propene tail of coumaric acid, which is the central intermediate in phenylpropanoid biosynthesis. From 4-Coumaroyl-CoA, 4-coumaroyl-CoA emanates the biosynthesis of myriad natural products including Monolignol, lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids. The coumaroyl component is produced from cinnamic acid. Phenylpropanoids are found throughout the plant kingdom, where they serve as essential components of a number of structural polymers, provide protection from ultraviolet light, defend against herbivores and pathogens, and also mediate plant-pollinator interactions as floral pigments and scent compounds. Hydroxycinnamic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palynology
Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments, sedimentary rocks, and even some metasedimentary rocks. Palynomorphs are the microscopic, acid-resistant organic remains and debris produced by a wide variety of plants, animals, and Protista that have existed since the late Proterozoic.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds., 2005, ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. It is the science that studies contemporary and fossil palynomorphs (paleopalynology), including pollen, spores, orbicules, dinocysts, acritarchs, chitinozoans and scolecodonts, together with particulate organic matter (POM) and kerogen found in sedimentary rocks and sediments. Palynology does not include diatoms, foraminiferans or other organisms with siliceous or calcareous tests. The name of the science and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Misc Pollen
Misc or MISC may refer to: * Misc, written abbreviation for miscellaneous, often used in programs * Misc (title), a gender neutral title * MISC Berhad, or Malaysia International Shipping Corporation * Minimal instruction set computer, a processor architecture * Moi International Sports Centre, in Kasarani, Kenya * Multisystem inflammatory syndrome in children, a post-infectious disease associated with COVID-19 * Malabar Independent Syrian Church The Malabar Independent Syrian Church (MISC), also known as the Thozhiyur Church, is a Christian church centred in Kerala, India. It is one of the churches of the Saint Thomas Christian community, which traces its origins to the evangelical ac ... See also * * * * Miscellaneous {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycopodium Clavatum
''Lycopodium clavatum'' (common club moss, stag's-horn clubmoss, running clubmoss, or ground pineBailey, L.H.; Bailey, E.Z.; the staff of the Liberty Hyde Bailey Hortorium. 1976. ''Hortus third: A concise dictionary of plants cultivated in the United States and Canada''. Macmillan, New York.) is the most widespread species in the genus ''Lycopodium'' in the Lycopodiaceae, clubmoss family. Description ''Lycopodium clavatum'' is a spore-bearing vascular plant, growing mainly prostrate along the ground with stems up to long; the stems are much branched, and densely clothed with small, spirally arranged microphyll leaf, leaves. The leaves are 3–5 mm long and 0.7–1 mm broad, tapered to a fine hair-like white point. The branches bearing strobili or spore cones turn erect, reaching above ground, and their leaves are modified as sporophylls that enclose the spore capsules or sporangia. The spore cones are yellow-green, long, and broad. The horizontal stems produce roots ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycopodium
''Lycopodium'' (from Ancient Greek ''lykos'', wolf and ''podion'', diminutive of ''pous'', foot) is a genus of clubmosses, also known as ground pines or creeping cedars, in the family Lycopodiaceae. Two very different circumscriptions of the genus are in use. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), ''Lycopodium'' is one of nine genera in the subfamily Lycopodioideae, and has from nine to 15 species. In other classifications, the genus is equivalent to the whole of the subfamily, since it includes all of the other genera. More than 40 species are accepted. Description They are flowerless, vascular, terrestrial or epiphytic plants, with widely branched, erect, prostrate, or creeping stems, with small, simple, needle-like or scale-like leaves that cover the stem and branches thickly. The stems usually creep along the ground, forking at intervals. The leaves contain a single, unbranched vascular strand, and are microphylls by definition. They are usually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycopodiaceae
The Lycopodiaceae (class Lycopodiopsida, order Lycopodiales) are an old family of vascular plants, including all of the core clubmosses and firmosses, comprising 17 accepted genera and about 500 known species. This family originated about 380 million years ago in the early Devonian, though the diversity within the family has been much more recent. "Wolf foot" is another common name for this family due to the resemblance of either the roots or branch tips to a wolf's paw. Description Members of Lycopodiaceae are not spermatophytes and so do not produce seeds. Instead they produce spores, which are oily and flammable, and are the most economically important aspects of these plants. The spores are of one size (i.e. the plants are isosporous) and are borne on a specialized structure at the apex of a shoot called a strobilus (plural: strobili), which resembles a tiny battle club, from which the common name derives. Members of the family share the common feature of having a microphy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naringenin
Naringenin is a flavanone from the flavonoid group of polyphenols. It is commonly found in citrus fruits, especially as the predominant flavonone in grapefruit. The fate and biological functions of naringenin in vivo are unknown, remaining under preliminary research, as of 2024. High consumption of dietary naringenin is generally regarded as safe, mainly due to its low bioavailability. Taking dietary supplements or consuming grapefruit excessively may impair the action of anticoagulants and increase the toxicity of various prescription drugs. Similar to furanocoumarins present in citrus fruits, naringenin may evoke CYP3A4 suppression in the liver and intestines, possibly resulting in adverse interactions with common medications. Structure Naringenin has the skeleton structure of a flavanone with three hydroxy groups at the 4′, 5, and 7 carbons. It may be found both in the aglycol form, naringenin, or in its glycosidic form, naringin, which has the addition of the disac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-Coumaric Acid
''p''-Coumaric acid is an organic compound with the formula HOC6H4CH=CHCO2H. It is one of the three isomers of coumaric acid. It is a white solid that is only slightly soluble in water but very soluble in ethanol and diethyl ether. Natural occurrences It is a precursor to many natural products, especially Monolignol, lignols, precursors to the woody mass that comprise many plants. Of the myriad occurrences, ''p''-coumaric acid can be found in ''Gnetum cleistostachyum''. In food ''p''-Coumaric acid can be found in a wide variety of edible plants and fungi such as peanuts, navy beans, tomatoes, carrots, basil and garlic. It is found in wine and vinegar. It is also found in barley grain. ''p''-Coumaric acid from pollen is a constituent of honey. Derivatives p-Coumaric acid glucoside, ''p''-Coumaric acid glucoside can also be found in commercial breads containing flaxseed. Diesters of ''p''-coumaric acid can be found in carnauba wax. Biosynthesis It is biosynthesized from c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic Compound
Aromatic compounds or arenes are organic compounds "with a chemistry typified by benzene" and "cyclically conjugated." The word "aromatic" originates from the past grouping of molecules based on odor, before their general chemical properties were understood. The current definition of aromatic compounds does not have any relation to their odor. Aromatic compounds are now defined as cyclic compounds satisfying Hückel's rule. Aromatic compounds have the following general properties: * Typically unreactive * Often non polar and hydrophobic * High carbon-hydrogen ratio * Burn with a strong sooty yellow flame, due to high C:H ratio * Undergo electrophilic substitution reactions and nucleophilic aromatic substitutions Arenes are typically split into two categories - benzoids, that contain a benzene derivative and follow the benzene ring model, and non-benzoids that contain other aromatic cyclic derivatives. Aromatic compounds are commonly used in organic synthesis and are involved in m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetal
In organic chemistry, an acetal is a functional group with the connectivity . Here, the R groups can be organic fragments (a carbon atom, with arbitrary other atoms attached to that) or hydrogen, while the R' groups must be organic fragments not hydrogen. The two R' groups can be equivalent to each other (a "symmetric acetal") or not (a "mixed acetal"). Acetals are formed from and convertible to aldehydes or ketones and have the same oxidation state at the central carbon, but have substantially different chemical stability and reactivity as compared to the analogous carbonyl compounds. The central carbon atom has four bonds to it, and is therefore saturated and has tetrahedral geometry. The term ketal is sometimes used to identify structures associated with ketones (both R groups organic fragments rather than hydrogen) rather than aldehydes and, historically, the term acetal was used specifically for the aldehyde-related cases (having at least one hydrogen in place of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aliphatic Compound
In organic chemistry, hydrocarbons ( compounds composed solely of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (; G. ''aleiphar'', fat, oil). Aliphatic compounds can be saturated (in which all the C-C bonds are single, requiring the structure to be completed, or 'saturated', by hydrogen) like hexane, or unsaturated, like hexene and hexyne. Open-chain compounds, whether straight or branched, and which contain no rings of any type, are always aliphatic. Cyclic compounds can be aliphatic if they are not aromatic. Structure Aliphatics compounds can be saturated, joined by single bonds ( alkanes), or unsaturated, with double bonds ( alkenes) or triple bonds ( alkynes). If other elements ( heteroatoms) are bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine, it is no longer a hydrocarbon, and therefore no longer an aliphatic compound. However, such compounds may still be referred to as al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
