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91-408: The test depends on the digestion of glucose to acetylmethylcarbinol . In the presence of oxygen and strong base, the acetylmethylcarbinol is oxidized to diacetyl, which then reacts with guanidine compounds commonly found in the peptone medium of the broth. Alpha-naphthol acts as a color enhancer, but the color change to red can occur without it. Procedure: First, add the alpha-naphthol; then, add

182-543: A pitch accent . In Modern Greek, all vowels and consonants are short. Many vowels and diphthongs once pronounced distinctly are pronounced as /i/ ( iotacism ). Some of the stops and glides in diphthongs have become fricatives , and the pitch accent has changed to a stress accent . Many of the changes took place in the Koine Greek period. The writing system of Modern Greek, however, does not reflect all pronunciation changes. The examples below represent Attic Greek in

273-440: A polarimeter since pure α- d -glucose has a specific rotation angle of +112.2° mL/(dm·g), pure β- d -glucose of +17.5° mL/(dm·g). When equilibrium has been reached after a certain time due to mutarotation, the angle of rotation is +52.7° mL/(dm·g). By adding acid or base, this transformation is much accelerated. The equilibration takes place via the open-chain aldehyde form. In dilute sodium hydroxide or other dilute bases,

364-471: A component of starch), cellulases (named after cellulose), chitinases (named after chitin), and more. Furthermore, for the cleavage of disaccharides, there are maltase, lactase, sucrase, trehalase , and others. In humans, about 70 genes are known that code for glycosidases. They have functions in the digestion and degradation of glycogen, sphingolipids , mucopolysaccharides , and poly( ADP-ribose ). Humans do not produce cellulases, chitinases, or trehalases, but

455-473: A general advancement in organic chemistry . This understanding occurred largely as a result of the investigations of Emil Fischer , a German chemist who received the 1902 Nobel Prize in Chemistry for his findings. The synthesis of glucose established the structure of organic material and consequently formed the first definitive validation of Jacobus Henricus van 't Hoff 's theories of chemical kinetics and

546-477: A lack of contemporaneous evidence. Several theories exist about what Hellenic dialect groups may have existed between the divergence of early Greek-like speech from the common Proto-Indo-European language and the Classical period. They have the same general outline but differ in some of the detail. The only attested dialect from this period is Mycenaean Greek , but its relationship to the historical dialects and

637-419: A lesser degree. Pamphylian Greek , spoken in a small area on the southwestern coast of Anatolia and little preserved in inscriptions, may be either a fifth major dialect group, or it is Mycenaean Greek overlaid by Doric, with a non-Greek native influence. Regarding the speech of the ancient Macedonians diverse theories have been put forward, but the epigraphic activity and the archaeological discoveries in

728-447: A lower tendency than other aldohexoses to react nonspecifically with the amine groups of proteins . This reaction— glycation —impairs or destroys the function of many proteins, e.g. in glycated hemoglobin . Glucose's low rate of glycation can be attributed to its having a more stable cyclic form compared to other aldohexoses, which means it spends less time than they do in its reactive open-chain form . The reason for glucose having

819-566: A net gain of two ATP molecules (four ATP molecules are produced during glycolysis through substrate-level phosphorylation, but two are required by enzymes used during the process). In aerobic respiration, a molecule of glucose is much more profitable in that a maximum net production of 30 or 32 ATP molecules (depending on the organism) is generated. Click on genes, proteins and metabolites below to link to respective articles. Tumor cells often grow comparatively quickly and consume an above-average amount of glucose by glycolysis, which leads to

910-605: A nutrition supplement in production of foodstuffs. Dextrose monohydrate is primarily consumed in North America as a corn syrup or high-fructose corn syrup . Anhydrous dextrose , on the other hand, is glucose that does not have any water molecules attached to it. Anhydrous chemical substances are commonly produced by eliminating water from a hydrated substance through methods such as heating or drying up (desiccation). Dextrose monohydrate can be dehydrated to anhydrous dextrose in industrial setting. Dextrose monohydrate

1001-550: A prefix /e-/, called the augment . This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect, and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). The two kinds of augment in Greek are syllabic and quantitative. The syllabic augment

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1092-550: A residue of carbon . Glucose has a pKa value of 12.16 at 25 °C (77 °F) in water. With six carbon atoms, it is classed as a hexose , a subcategory of the monosaccharides . d -Glucose is one of the sixteen aldohexose stereoisomers . The d - isomer , d -glucose, also known as dextrose, occurs widely in nature, but the l -isomer, l -glucose , does not. Glucose can be obtained by hydrolysis of carbohydrates such as milk sugar ( lactose ), cane sugar (sucrose), maltose , cellulose , glycogen , etc. Dextrose

1183-425: A ring of carbons closed by one oxygen atom. In aqueous solution, however, more than 99% of glucose molecules exist as pyranose forms. The open-chain form is limited to about 0.25%, and furanose forms exist in negligible amounts. The terms "glucose" and " D -glucose" are generally used for these cyclic forms as well. The ring arises from the open-chain form by an intramolecular nucleophilic addition reaction between

1274-608: A separate historical stage, though its earliest form closely resembles Attic Greek , and its latest form approaches Medieval Greek . There were several regional dialects of Ancient Greek; Attic Greek developed into Koine. Ancient Greek was a pluricentric language , divided into many dialects. The main dialect groups are Attic and Ionic , Aeolic , Arcadocypriot , and Doric , many of them with several subdivisions. Some dialects are found in standardized literary forms in literature , while others are attested only in inscriptions. There are also several historical forms. Homeric Greek

1365-630: A standard subject of study in educational institutions of the Western world since the Renaissance . This article primarily contains information about the Epic and Classical periods of the language, which are the best-attested periods and considered most typical of Ancient Greek. From the Hellenistic period ( c.  300 BC ), Ancient Greek was followed by Koine Greek , which is regarded as

1456-413: A subgroup of the glycosidases, first catalyze the hydrolysis of long-chain glucose-containing polysaccharides, removing terminal glucose. In turn, disaccharides are mostly degraded by specific glycosidases to glucose. The names of the degrading enzymes are often derived from the particular poly- and disaccharide; inter alia, for the degradation of polysaccharide chains there are amylases (named after amylose,

1547-510: A vowel or /n s r/ ; final stops were lost, as in γάλα "milk", compared with γάλακτος "of milk" (genitive). Ancient Greek of the classical period also differed in both the inventory and distribution of original PIE phonemes due to numerous sound changes, notably the following: The pronunciation of Ancient Greek was very different from that of Modern Greek . Ancient Greek had long and short vowels ; many diphthongs ; double and single consonants; voiced, voiceless, and aspirated stops ; and

1638-441: Is dextrorotatory , meaning it will rotate the direction of polarized light clockwise as seen looking toward the light source. The effect is due to the chirality of the molecules, and indeed the mirror-image isomer, l -(−)-glucose, is levorotatory (rotates polarized light counterclockwise) by the same amount. The strength of the effect is different for each of the five tautomers . The d - prefix does not refer directly to

1729-406: Is 198.17 g/mol, that for anhydrous D-glucose is 180.16 g/mol The density of these two forms of glucose is also different. In terms of chemical structure, glucose is a monosaccharide, that is, a simple sugar. Glucose contains six carbon atoms and an aldehyde group , and is therefore an aldohexose . The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form—due to

1820-473: Is 31 °C (88 °F) and the Gordon–Taylor constant (an experimentally determined constant for the prediction of the glass transition temperature for different mass fractions of a mixture of two substances) is 4.5. A open-chain form of glucose makes up less than 0.02% of the glucose molecules in an aqueous solution at equilibrium. The rest is one of two cyclic hemiacetal forms. In its open-chain form,

1911-466: Is a chemical classifier denoting a sugar. Glucose was first isolated from raisins in 1747 by the German chemist Andreas Marggraf . Glucose was discovered in grapes by another German chemist – Johann Tobias Lowitz  – in 1792, and distinguished as being different from cane sugar ( sucrose ). Glucose is the term coined by Jean Baptiste Dumas in 1838, which has prevailed in

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2002-408: Is a glucose molecule with an additional water molecule attached. Its chemical formula is C 6 H 12 O 6  ·  H 2 O . Dextrose monohydrate is also called hydrated D-glucose , and commonly manufactured from plant starches. Dextrose monohydrate is utilized as the predominant type of dextrose in food applications, such as beverage mixes—it is a common form of glucose widely used as

2093-570: Is a literary form of Archaic Greek (derived primarily from Ionic and Aeolic) used in the epic poems , the Iliad and the Odyssey , and in later poems by other authors. Homeric Greek had significant differences in grammar and pronunciation from Classical Attic and other Classical-era dialects. The origins, early form and development of the Hellenic language family are not well understood because of

2184-418: Is added to stems beginning with consonants, and simply prefixes e (stems beginning with r , however, add er ). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel: Some verbs augment irregularly; the most common variation is e → ei . The irregularity can be explained diachronically by the loss of s between vowels, or that of the letter w , which affected

2275-508: Is an open-chain to a small extent and is present predominantly as α- or β- pyranose , which interconvert. From aqueous solutions, the three known forms can be crystallized: α-glucopyranose, β-glucopyranose and α-glucopyranose monohydrate. Glucose is a building block of the disaccharides lactose and sucrose (cane or beet sugar), of oligosaccharides such as raffinose and of polysaccharides such as starch , amylopectin , glycogen , and cellulose . The glass transition temperature of glucose

2366-666: Is called 'East Greek'. Arcadocypriot apparently descended more closely from the Mycenaean Greek of the Bronze Age. Boeotian Greek had come under a strong Northwest Greek influence, and can in some respects be considered a transitional dialect, as exemplified in the poems of the Boeotian poet Pindar who wrote in Doric with a small Aeolic admixture. Thessalian likewise had come under Northwest Greek influence, though to

2457-514: Is commonly commercially manufactured from starches , such as corn starch in the US and Japan, from potato and wheat starch in Europe, and from tapioca starch in tropical areas. The manufacturing process uses hydrolysis via pressurized steaming at controlled pH in a jet followed by further enzymatic depolymerization. Unbonded glucose is one of the main ingredients of honey . The term dextrose

2548-646: Is composed of approximately 9.5% water by mass; through the process of dehydration, this water content is eliminated to yield anhydrous (dry) dextrose. Anhydrous dextrose has the chemical formula C 6 H 12 O 6 , without any water molecule attached which is the same as glucose. Anhydrous dextrose on open air tends to absorb moisture and transform to the monohydrate, and it is more expensive to produce. Anhydrous dextrose (anhydrous D-glucose) has increased stability and increased shelf life, has medical applications, such as in oral glucose tolerance test . Whereas molecular weight (molar mass) for D-glucose monohydrate

2639-448: Is considered by some linguists to have been closely related to Greek . Among Indo-European branches with living descendants, Greek is often argued to have the closest genetic ties with Armenian (see also Graeco-Armenian ) and Indo-Iranian languages (see Graeco-Aryan ). Ancient Greek differs from Proto-Indo-European (PIE) and other Indo-European languages in certain ways. In phonotactics , ancient Greek words could end only in

2730-605: Is naturally occurring and is found in its free state in fruits and other parts of plants. In animals, it is released from the breakdown of glycogen in a process known as glycogenolysis . Glucose, as intravenous sugar solution , is on the World Health Organization's List of Essential Medicines . It is also on the list in combination with sodium chloride (table salt). The name glucose is derived from Ancient Greek γλεῦκος ( gleûkos ) 'wine, must', from γλυκύς ( glykýs ) 'sweet'. The suffix -ose

2821-423: Is often used in a clinical (related to patient's health status) or nutritional context (related to dietary intake, such as food labels or dietary guidelines), while "glucose" is used in a biological or physiological context (chemical processes and molecular interactions), but both terms refer to the same molecule, specifically D-glucose. Dextrose monohydrate is the hydrated form of D-glucose, meaning that it

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2912-483: Is produced by conversion of food, but it is also synthesized from other metabolites in the body's cells. In humans, the breakdown of glucose-containing polysaccharides happens in part already during chewing by means of amylase , which is contained in saliva , as well as by maltase , lactase , and sucrase on the brush border of the small intestine . Glucose is a building block of many carbohydrates and can be split off from them using certain enzymes. Glucosidases ,

3003-440: Is produced by most cell types and is of particular importance for nerve cells and pancreatic β-cells . GLUT3 is highly expressed in nerve cells. Glucose from the bloodstream is taken up by GLUT4 from muscle cells (of the skeletal muscle and heart muscle ) and fat cells . GLUT14 is expressed exclusively in testicles . Excess glucose is broken down and converted into fatty acids, which are stored as triglycerides . In

3094-415: Is termed glycogenolysis, the cleavage of starch is called starch degradation. The metabolic pathway that begins with molecules containing two to four carbon atoms (C) and ends in the glucose molecule containing six carbon atoms is called gluconeogenesis and occurs in all living organisms. The smaller starting materials are the result of other metabolic pathways. Ultimately almost all biomolecules come from

3185-485: Is the phosphorylation of glucose by a hexokinase to form glucose 6-phosphate . The main reason for the immediate phosphorylation of glucose is to prevent its diffusion out of the cell as the charged phosphate group prevents glucose 6-phosphate from easily crossing the cell membrane . Furthermore, addition of the high-energy phosphate group activates glucose for subsequent breakdown in later steps of glycolysis. In anaerobic respiration, one glucose molecule produces

3276-467: Is the human body's key source of energy, through aerobic respiration, providing about 3.75  kilocalories (16  kilojoules ) of food energy per gram. Breakdown of carbohydrates (e.g., starch) yields mono- and disaccharides , most of which is glucose. Through glycolysis and later in the reactions of the citric acid cycle and oxidative phosphorylation , glucose is oxidized to eventually form carbon dioxide and water, yielding energy mostly in

3367-457: Is used by plants to make cellulose —the most abundant carbohydrate in the world—for use in cell walls , and by all living organisms to make adenosine triphosphate (ATP), which is used by the cell as energy. In energy metabolism , glucose is the most important source of energy in all organisms . Glucose for metabolism is stored as a polymer , in plants mainly as amylose and amylopectin , and in animals as glycogen . Glucose circulates in

3458-481: The Crabtree effect . Glucose can also degrade to form carbon dioxide through abiotic means. This has been demonstrated to occur experimentally via oxidation and hydrolysis at 22 °C and a pH of 2.5. Glucose is a ubiquitous fuel in biology . It is used as an energy source in organisms, from bacteria to humans, through either aerobic respiration , anaerobic respiration (in bacteria), or fermentation . Glucose

3549-759: The Greek region of Macedonia during the last decades has brought to light documents, among which the first texts written in Macedonian , such as the Pella curse tablet , as Hatzopoulos and other scholars note. Based on the conclusions drawn by several studies and findings such as Pella curse tablet , Emilio Crespo and other scholars suggest that ancient Macedonian was a Northwest Doric dialect , which shares isoglosses with its neighboring Thessalian dialects spoken in northeastern Thessaly . Some have also suggested an Aeolic Greek classification. The Lesbian dialect

3640-580: The Haworth projection , the designation "α-" means that the hydroxyl group attached to C-1 and the −CH 2 OH group at C-5 lies on opposite sides of the ring's plane (a trans arrangement), while "β-" means that they are on the same side of the plane (a cis arrangement). Therefore, the open-chain isomer D -glucose gives rise to four distinct cyclic isomers: α- D -glucopyranose, β- D -glucopyranose, α- D -glucofuranose, and β- D -glucofuranose. These five structures exist in equilibrium and interconvert, and

3731-439: The basolateral side of the intestinal epithelial cells via the glucose transporter GLUT2 , as well uptake into liver cells , kidney cells, cells of the islets of Langerhans , neurons , astrocytes , and tanycytes . Glucose enters the liver via the portal vein and is stored there as a cellular glycogen. In the liver cell, it is phosphorylated by glucokinase at position 6 to form glucose 6-phosphate , which cannot leave

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3822-586: The equatorial position in the form of β- d -glucose, is more readily accessible to chemical reactions, for example, for esterification or acetal formation. For this reason, d -glucose is also a highly preferred building block in natural polysaccharides (glycans). Polysaccharides that are composed solely of glucose are termed glucans . Glucose is produced by plants through photosynthesis using sunlight, water and carbon dioxide and can be used by all living organisms as an energy and carbon source. However, most glucose does not occur in its free form, but in

3913-481: The kidneys , glucose in the urine is absorbed via SGLT1 and SGLT2 in the apical cell membranes and transmitted via GLUT2 in the basolateral cell membranes. About 90% of kidney glucose reabsorption is via SGLT2 and about 3% via SGLT1. In plants and some prokaryotes , glucose is a product of photosynthesis . Glucose is also formed by the breakdown of polymeric forms of glucose like glycogen (in animals and mushrooms ) or starch (in plants). The cleavage of glycogen

4004-501: The present , future , and imperfect are imperfective in aspect; the aorist , present perfect , pluperfect and future perfect are perfective in aspect. Most tenses display all four moods and three voices, although there is no future subjunctive or imperative. Also, there is no imperfect subjunctive, optative or imperative. The infinitives and participles correspond to the finite combinations of tense, aspect, and voice. The indicative of past tenses adds (conceptually, at least)

4095-411: The "envelope" conformations of cyclopentane . In the solid state, only the glucopyranose forms are observed. Some derivatives of glucofuranose, such as 1,2- O -isopropylidene- D -glucofuranose are stable and can be obtained pure as crystalline solids. For example, reaction of α-D-glucose with para -tolylboronic acid H 3 C−(C 6 H 4 )−B(OH) 2 reforms the normal pyranose ring to yield

4186-421: The 4-fold ester α-D-glucofuranose-1,2:3,5-bis( p -tolylboronate). Mutarotation consists of a temporary reversal of the ring-forming reaction, resulting in the open-chain form, followed by a reforming of the ring. The ring closure step may use a different −OH group than the one recreated by the opening step (thus switching between pyranose and furanose forms), or the new hemiacetal group created on C-1 may have

4277-1031: The 5th century BC. Ancient pronunciation cannot be reconstructed with certainty, but Greek from the period is well documented, and there is little disagreement among linguists as to the general nature of the sounds that the letters represent. /oː/ raised to [uː] , probably by the 4th century BC. Greek, like all of the older Indo-European languages , is highly inflected. It is highly archaic in its preservation of Proto-Indo-European forms. In ancient Greek, nouns (including proper nouns) have five cases ( nominative , genitive , dative , accusative , and vocative ), three genders ( masculine , feminine , and neuter ), and three numbers (singular, dual , and plural ). Verbs have four moods ( indicative , imperative , subjunctive , and optative ) and three voices (active, middle, and passive ), as well as three persons (first, second, and third) and various other forms. Verbs are conjugated through seven combinations of tenses and aspect (generally simply called "tenses"):

4368-495: The Archaic period of ancient Greek (see Homeric Greek for more details): Μῆνιν ἄειδε, θεά, Πηληϊάδεω Ἀχιλῆος οὐλομένην, ἣ μυρί' Ἀχαιοῖς ἄλγε' ἔθηκε, πολλὰς δ' ἰφθίμους ψυχὰς Ἄϊδι προΐαψεν ἡρώων, αὐτοὺς δὲ ἑλώρια τεῦχε κύνεσσιν οἰωνοῖσί τε πᾶσι· Διὸς δ' ἐτελείετο βουλή· ἐξ οὗ δὴ τὰ πρῶτα διαστήτην ἐρίσαντε Ἀτρεΐδης τε ἄναξ ἀνδρῶν καὶ δῖος Ἀχιλλεύς. The beginning of Apology by Plato exemplifies Attic Greek from

4459-450: The aldehyde group (at C-1) and either the C-4 or C-5 hydroxyl group, forming a hemiacetal linkage, −C(OH)H−O− . The reaction between C-1 and C-5 yields a six-membered heterocyclic system called a pyranose, which is a monosaccharide sugar (hence "-ose") containing a derivatised pyran skeleton. The (much rarer) reaction between C-1 and C-4 yields a five-membered furanose ring, named after

4550-402: The ambient environment. Glucose concentrations in the atmosphere are detected via collection of samples by aircraft and are known to vary from location to location. For example, glucose concentrations in atmospheric air from inland China range from 0.8 to 20.1 pg/L, whereas east coastal China glucose concentrations range from 10.3 to 142 pg/L. In humans, glucose is metabolized by glycolysis and

4641-550: The aorist. Following Homer 's practice, the augment is sometimes not made in poetry , especially epic poetry. The augment sometimes substitutes for reduplication; see below. Almost all forms of the perfect, pluperfect, and future perfect reduplicate the initial syllable of the verb stem. (A few irregular forms of perfect do not reduplicate, whereas a handful of irregular aorists reduplicate.) The three types of reduplication are: Irregular duplication can be understood diachronically. For example, lambanō (root lab ) has

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4732-536: The arrangements of chemical bonds in carbon-bearing molecules. Between 1891 and 1894, Fischer established the stereochemical configuration of all the known sugars and correctly predicted the possible isomers , applying Van 't Hoff equation of asymmetrical carbon atoms. The names initially referred to the natural substances. Their enantiomers were given the same name with the introduction of systematic nomenclatures, taking into account absolute stereochemistry (e.g. Fischer nomenclature , d / l nomenclature). For

4823-435: The assimilation of carbon dioxide in plants and microbes during photosynthesis. The free energy of formation of α- d -glucose is 917.2 kilojoules per mole. In humans, gluconeogenesis occurs in the liver and kidney, but also in other cell types. In the liver about 150 g (5.3 oz) of glycogen are stored, in skeletal muscle about 250 g (8.8 oz). However, the glucose released in muscle cells upon cleavage of

4914-419: The augment when it was word-initial. In verbs with a preposition as a prefix, the augment is placed not at the start of the word, but between the preposition and the original verb. For example, προσ(-)βάλλω (I attack) goes to προσ έ βαλoν in the aorist. However compound verbs consisting of a prefix that is not a preposition retain the augment at the start of the word: αὐτο(-)μολῶ goes to ηὐ τομόλησα in

5005-528: The bacteria in the gut microbiota do. In order to get into or out of cell membranes of cells and membranes of cell compartments, glucose requires special transport proteins from the major facilitator superfamily . In the small intestine (more precisely, in the jejunum ), glucose is taken up into the intestinal epithelium with the help of glucose transporters via a secondary active transport mechanism called sodium ion-glucose symport via sodium/glucose cotransporter 1 (SGLT1). Further transfer occurs on

5096-431: The blood of animals as blood sugar . The naturally occurring form is d -glucose, while its stereoisomer l -glucose is produced synthetically in comparatively small amounts and is less biologically active. Glucose is a monosaccharide containing six carbon atoms and an aldehyde group, and is therefore an aldohexose . The glucose molecule can exist in an open-chain (acyclic) as well as ring (cyclic) form. Glucose

5187-428: The cell. Glucose 6-phosphatase can convert glucose 6-phosphate back into glucose exclusively in the liver, so the body can maintain a sufficient blood glucose concentration. In other cells, uptake happens by passive transport through one of the 14 GLUT proteins. In the other cell types, phosphorylation occurs through a hexokinase , whereupon glucose can no longer diffuse out of the cell. The glucose transporter GLUT1

5278-438: The center of Greek scholarship, this division of people and language is quite similar to the results of modern archaeological-linguistic investigation. One standard formulation for the dialects is: West vs. non-West Greek is the strongest-marked and earliest division, with non-West in subsets of Ionic-Attic (or Attic-Ionic) and Aeolic vs. Arcadocypriot, or Aeolic and Arcado-Cypriot vs. Ionic-Attic. Often non-West

5369-469: The chemical literature. Friedrich August Kekulé proposed the term dextrose (from the Latin dexter , meaning "right"), because in aqueous solution of glucose, the plane of linearly polarized light is turned to the right. In contrast, l-fructose (usually referred to as d -fructose) (a ketohexose) and l-glucose ( l -glucose) turn linearly polarized light to the left. The earlier notation according to

5460-401: The cyclic ether furan . In either case, each carbon in the ring has one hydrogen and one hydroxyl attached, except for the last carbon (C-4 or C-5) where the hydroxyl is replaced by the remainder of the open molecule (which is −(C(CH 2 OH)HOH)−H or −(CHOH)−H respectively). The ring-closing reaction can give two products, denoted "α-" and "β-". When a glucopyranose molecule is drawn in

5551-615: The dialect of Sparta ), and Northern Peloponnesus Doric (including Corinthian ). All the groups were represented by colonies beyond Greece proper as well, and these colonies generally developed local characteristics, often under the influence of settlers or neighbors speaking different Greek dialects. After the conquests of Alexander the Great in the late 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek , but with influence from other dialects. This dialect slowly replaced most of

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5642-585: The discovery of the metabolism of glucose Otto Meyerhof received the Nobel Prize in Physiology or Medicine in 1922. Hans von Euler-Chelpin was awarded the Nobel Prize in Chemistry along with Arthur Harden in 1929 for their "research on the fermentation of sugar and their share of enzymes in this process". In 1947, Bernardo Houssay (for his discovery of the role of the pituitary gland in

5733-399: The enzymes, determine which reactions are possible. The metabolic pathway of glycolysis is used by almost all living beings. An essential difference in the use of glycolysis is the recovery of NADPH as a reductant for anabolism that would otherwise have to be generated indirectly. Ancient Greek Ancient Greek ( Ἑλληνῐκή , Hellēnikḗ ; [hellɛːnikɛ́ː] ) includes

5824-597: The form of adenosine triphosphate (ATP). The insulin reaction, and other mechanisms, regulate the concentration of glucose in the blood. The physiological caloric value of glucose, depending on the source, is 16.2 kilojoules per gram or 15.7 kJ/g (3.74 kcal/g). The high availability of carbohydrates from plant biomass has led to a variety of methods during evolution, especially in microorganisms, to utilize glucose for energy and carbon storage. Differences exist in which end product can no longer be used for energy production. The presence of individual genes, and their gene products,

5915-406: The form of its polymers, i.e. lactose, sucrose, starch and others which are energy reserve substances, and cellulose and chitin , which are components of the cell wall in plants or fungi and arthropods , respectively. These polymers, when consumed by animals, fungi and bacteria, are degraded to glucose using enzymes. All animals are also able to produce glucose themselves from certain precursors as

6006-460: The formation of lactate, the end product of fermentation in mammals, even in the presence of oxygen. This is called the Warburg effect . For the increased uptake of glucose in tumors various SGLT and GLUT are overly produced. In yeast , ethanol is fermented at high glucose concentrations, even in the presence of oxygen (which normally leads to respiration rather than fermentation). This is called

6097-673: The forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek ( c.  1400–1200 BC ), Dark Ages ( c.  1200–800 BC ), the Archaic or Epic period ( c.  800–500 BC ), and the Classical period ( c.  500–300 BC ). Ancient Greek was the language of Homer and of fifth-century Athenian historians, playwrights, and philosophers . It has contributed many words to English vocabulary and has been

6188-416: The four cyclic isomers interconvert over a time scale of hours, in a process called mutarotation . Starting from any proportions, the mixture converges to a stable ratio of α:β 36:64. The ratio would be α:β 11:89 if it were not for the influence of the anomeric effect . Mutarotation is considerably slower at temperatures close to 0 °C (32 °F). Whether in water or the solid form, d -(+)-glucose

6279-726: The glucose degradation in animals occurs anaerobic to lactate via lactic acid fermentation and releases much less energy. Muscular lactate enters the liver through the bloodstream in mammals, where gluconeogenesis occurs ( Cori cycle ). With a high supply of glucose, the metabolite acetyl-CoA from the Krebs cycle can also be used for fatty acid synthesis . Glucose is also used to replenish the body's glycogen stores, which are mainly found in liver and skeletal muscle. These processes are hormonally regulated. In other living organisms, other forms of fermentation can occur. The bacterium Escherichia coli can grow on nutrient media containing glucose as

6370-526: The glucose molecule has an open (as opposed to cyclic ) unbranched backbone of six carbon atoms, where C-1 is part of an aldehyde group H(C=O)− . Therefore, glucose is also classified as an aldose , or an aldohexose . The aldehyde group makes glucose a reducing sugar giving a positive reaction with the Fehling test . In solutions, the open-chain form of glucose (either " D -" or " L -") exists in equilibrium with several cyclic isomers , each containing

6461-453: The glycation of proteins or lipids . In contrast, enzyme -regulated addition of sugars to protein is called glycosylation and is essential for the function of many proteins. Ingested glucose initially binds to the receptor for sweet taste on the tongue in humans. This complex of the proteins T1R2 and T1R3 makes it possible to identify glucose-containing food sources. Glucose mainly comes from food—about 300 g (11 oz) per day

6552-519: The glycogen can not be delivered to the circulation because glucose is phosphorylated by the hexokinase, and a glucose-6-phosphatase is not expressed to remove the phosphate group. Unlike for glucose, there is no transport protein for glucose-6-phosphate . Gluconeogenesis allows the organism to build up glucose from other metabolites, including lactate or certain amino acids , while consuming energy. The renal tubular cells can also produce glucose. Glucose also can be found outside of living organisms in

6643-561: The historical Dorians . The invasion is known to have displaced population to the later Attic-Ionic regions, who regarded themselves as descendants of the population displaced by or contending with the Dorians. The Greeks of this period believed there were three major divisions of all Greek people – Dorians, Aeolians, and Ionians (including Athenians), each with their own defining and distinctive dialects. Allowing for their oversight of Arcadian, an obscure mountain dialect, and Cypriot, far from

6734-476: The historical circumstances of the times imply that the overall groups already existed in some form. Scholars assume that major Ancient Greek period dialect groups developed not later than 1120 BC, at the time of the Dorian invasions —and that their first appearances as precise alphabetic writing began in the 8th century BC. The invasion would not be "Dorian" unless the invaders had some cultural relationship to

6825-440: The interconversion is much more rapid with acid catalysis . The other open-chain isomer L -glucose similarly gives rise to four distinct cyclic forms of L -glucose, each the mirror image of the corresponding D -glucose. The glucopyranose ring (α or β) can assume several non-planar shapes, analogous to the "chair" and "boat" conformations of cyclohexane . Similarly, the glucofuranose ring may assume several shapes, analogous to

6916-710: The metabolism of glucose and the derived carbohydrates) as well as Carl and Gerty Cori (for their discovery of the conversion of glycogen from glucose) received the Nobel Prize in Physiology or Medicine. In 1970, Luis Leloir was awarded the Nobel Prize in Chemistry for the discovery of glucose-derived sugar nucleotides in the biosynthesis of carbohydrates. Glucose forms white or colorless solids that are highly soluble in water and acetic acid but poorly soluble in methanol and ethanol . They melt at 146 °C (295 °F) ( α ) and 150 °C (302 °F) ( beta ), decompose starting at 188 °C (370 °F) with release of various volatile products, ultimately leaving

7007-415: The monosaccharides mannose , glucose and fructose interconvert (via a Lobry de Bruyn–Alberda–Van Ekenstein transformation ), so that a balance between these isomers is formed. This reaction proceeds via an enediol : [REDACTED] Glucose is the most abundant monosaccharide. Glucose is also the most widely used aldohexose in most living organisms. One possible explanation for this is that glucose has

7098-441: The most stable cyclic form of all the aldohexoses is that its hydroxy groups (with the exception of the hydroxy group on the anomeric carbon of d -glucose) are in the equatorial position . Presumably, glucose is the most abundant natural monosaccharide because it is less glycated with proteins than other monosaccharides. Another hypothesis is that glucose, being the only d -aldohexose that has all five hydroxy substituents in

7189-506: The need arises. Neurons , cells of the renal medulla and erythrocytes depend on glucose for their energy production. In adult humans, there is about 18 g (0.63 oz) of glucose, of which about 4 g (0.14 oz) is present in the blood. Approximately 180–220 g (6.3–7.8 oz) of glucose is produced in the liver of an adult in 24 hours. Many of the long-term complications of diabetes (e.g., blindness , kidney failure , and peripheral neuropathy ) are probably due to

7280-508: The older dialects, although the Doric dialect has survived in the Tsakonian language , which is spoken in the region of modern Sparta. Doric has also passed down its aorist terminations into most verbs of Demotic Greek . By about the 6th century AD, the Koine had slowly metamorphosed into Medieval Greek . Phrygian is an extinct Indo-European language of West and Central Anatolia , which

7371-466: The optical properties of the compound. It indicates that the C-5 chiral centre has the same handedness as that of d -glyceraldehyde (which was so labelled because it is dextrorotatory). The fact that d -glucose is dextrorotatory is a combined effect of its four chiral centres, not just of C-5; some of the other d -aldohexoses are levorotatory. The conversion between the two anomers can be observed in

7462-434: The pentose phosphate pathway. Glycolysis is used by all living organisms, with small variations, and all organisms generate energy from the breakdown of monosaccharides. In the further course of the metabolism, it can be completely degraded via oxidative decarboxylation , the citric acid cycle (synonym Krebs cycle ) and the respiratory chain to water and carbon dioxide. If there is not enough oxygen available for this,

7553-487: The perfect stem eilēpha (not * lelēpha ) because it was originally slambanō , with perfect seslēpha , becoming eilēpha through compensatory lengthening. Reduplication is also visible in the present tense stems of certain verbs. These stems add a syllable consisting of the root's initial consonant followed by i . A nasal stop appears after the reduplication in some verbs. The earliest extant examples of ancient Greek writing ( c.  1450 BC ) are in

7644-802: The potassium hydroxide. A reversal in the order of the reagents being added may result in a weak-positive or false-negative reaction. VP is one of the four tests of the IMViC series, which tests for evidence of an enteric bacterium. The other three tests include: the indole test [I], the methyl red test [M], and the citrate test [C]. VP positive organisms include Enterobacter , Klebsiella , Serratia marcescens , Hafnia alvei , Vibrio cholerae biotype El Tor , and Vibrio alginolyticus . VP negative organisms include Citrobacter sp., Shigella , Yersinia , Edwardsiella , Salmonella , Vibrio furnissii , Vibrio fluvialis , Vibrio vulnificus , and Vibrio parahaemolyticus . The reaction

7735-412: The presence of alcohol and aldehyde or ketone functional groups, the form having the straight chain can easily convert into a chair-like hemiacetal ring structure commonly found in carbohydrates. Glucose is present in solid form as a monohydrate with a closed pyran ring (α-glucopyranose monohydrate, sometimes known less precisely by dextrose hydrate). In aqueous solution, on the other hand, it

7826-468: The rotation of the plane of linearly polarized light ( d and l -nomenclature) was later abandoned in favor of the d - and l -notation , which refers to the absolute configuration of the asymmetric center farthest from the carbonyl group, and in concordance with the configuration of d - or l -glyceraldehyde. Since glucose is a basic necessity of many organisms, a correct understanding of its chemical makeup and structure contributed greatly to

7917-510: The same or opposite handedness as the original one (thus switching between the α and β forms). Thus, though the open-chain form is barely detectable in solution, it is an essential component of the equilibrium. The open-chain form is thermodynamically unstable , and it spontaneously isomerizes to the cyclic forms. (Although the ring closure reaction could in theory create four- or three-atom rings, these would be highly strained, and are not observed in practice.) In solutions at room temperature ,

8008-499: The sole carbon source. In some bacteria and, in modified form, also in archaea, glucose is degraded via the Entner-Doudoroff pathway . With Glucose, a mechanism for gene regulation was discovered in E. coli , the catabolite repression (formerly known as glucose effect ). Use of glucose as an energy source in cells is by either aerobic respiration, anaerobic respiration, or fermentation. The first step of glycolysis

8099-517: The syllabic script Linear B . Beginning in the 8th century BC, however, the Greek alphabet became standard, albeit with some variation among dialects. Early texts are written in boustrophedon style, but left-to-right became standard during the classic period. Modern editions of ancient Greek texts are usually written with accents and breathing marks , interword spacing , modern punctuation , and sometimes mixed case , but these were all introduced later. The beginning of Homer 's Iliad exemplifies

8190-480: Was Aeolic. For example, fragments of the works of the poet Sappho from the island of Lesbos are in Aeolian. Most of the dialect sub-groups listed above had further subdivisions, generally equivalent to a city-state and its surrounding territory, or to an island. Doric notably had several intermediate divisions as well, into Island Doric (including Cretan Doric ), Southern Peloponnesus Doric (including Laconian ,

8281-529: Was developed by Daniel Wilhelm Otto Voges and Bernhard Proskauer , German bacteriologists in 1898 at the Institute for Infectious Diseases . Glucose Glucose is a sugar with the molecular formula C 6 H 12 O 6 . It is overall the most abundant monosaccharide , a subcategory of carbohydrates . It is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight. It

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