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Chemosynthesis

/ˌkēmōˈsinTHəsəs/  /ˌkemō-/ Noun, pl. chemosyntheses 1. (Biochemistry) The biological conversion of one or more carbon molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic molecules (e.g. hydrogen gas, hydrogen sulfide) or methane as a source of energy, rather than sunlight, as in photosynthesis. (Wikipedia.org) 2. The production of carbohydrates and other compounds from simple compounds such as carbon dioxide, using the oxidation of chemical nutrients as a source of energy rather than sunlight; it is limited to certain bacteria and fungi. (wiktionary.org) 3. (Biology) Process by which some organisms, such as certain bacteria, use chemical energy to produce carbohydrates. (www.biology-online.org) 4. The synthesis of organic compounds by bacteria or other living organisms using energy derived from reactions involving inorganic chemicals, typically in the absence of sunlight. (Google...

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Chiasma

/kīˈazmə/ Noun, pl. Chiasmata 1. (Genetics) Thought to be the point where two homologous non-sister chromatids exchange genetic material during chromosomal crossover during meiosis (sister chromatids also form chiasmata between each other, but because their genetic material is identical, it does not cause any change in the resulting daughter cells). (wikipedia.org) 2. A point at which paired chromosomes remain in contact during the first metaphase of meiosis, and at which crossing over and exchange of genetic material occur between the strands. (Google Dictionary) 3. The point of contact between paired chromatids during meiosis, resulting in a cross-shaped configuration and representing the cytological manifestation of crossing over like the letter X. (biology-online.org) Word origin: Modern Latin, from Ancient Greek χίασμα, from χίαζειν (“to mark with the letter chi”). Syn:...

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Chlorophyll

/klôr′əfil/ Noun 1. The green pigment found in the chloroplasts of higher plants and in cells of photosynthetic microorganisms (e.g. photosynthetic bacteria), which is primarily involved in absorbing light energy for photosynthesis. (biology-online.org) Syn: “Green pigment” Word origin: from the Greek words χλωρος, chloros (green) + φύλλον, phyllon...

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Cholesterol

/kəˈlestəˌrôl/  /-ˌrōl/ Noun 1. (Science: biochemistry) A pearly, fatlike steroid alcohol, C27H45OH, crystallizing in the form of leaflets or plates from dilute alcohol and found in animal fats and oils, in bile, blood, brain tissue, milk, yolk of egg, myelin sheaths of nerve fibres, the liver, kidneys and adrenal glands. (biology-online.org) It constitutes a large part of the most frequently occurring type of gallstones and occurs in atheroma of the arteries, in various cysts and in carcinomatous tissue. Most of the bodys cholesterol is synthesised in the liver, but some is absorbed from the diet. It is a precursor of bile acids and is important in the synthesis of steroid hormones. (biology-online.org) 2. (Science: chemical) A commercial preparation of cholesterol is used as a pharmaceutic aid. (biology-online.org) 3. (Biochemistry) A sterol lipid synthesized by the liver and transported in the bloodstream to the membranes of all animal cells; it plays a central role in many biochemical processes and, as a lipoprotein that coats the walls of blood vessels, is associated with cardiovascular disease. 4. A compound of the sterol type found in most body tissues, including the blood and the nerves. Cholesterol and its derivatives are important constituents of cell membranes and precursors of other steroid compounds, but high concentrations in the blood (mainly derived from animal fats in the diet) are thought to promote atherosclerosis. (Google Dictionary) 5....

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Chromosome

/ˈkrōməˌsōm/ Noun, pl. chromosomes 1. A structure within the cell that bears the genetic material as a threadlike linear strand of DNA bonded to various proteins in the nucleus of eukaryotic cells, or as a circular strand of DNA (or RNA in some viruses) in the cytoplasm of prokaryotes and in the mitochondrion and chloroplast of certain eukaryotes. (biology-online.org) 2. A threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes. (Google Dictionary) 3. (Biology, Cytology) A structure in the cell nucleus that contains DNA, histone protein, and other structural proteins. (wiktionary.org) Word origin: 19th century: from German Chromosom, ultimately from Ancient Greek χρῶμα (khroma, “colour”) + σῶμα (“body”) (because they are stained under the...

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