Glucose Essay, Research Paper
Glucose is one of the most essential and plentiful carbohydrates found on Earth. It is very important and crucial for many life functions, and procedures. Glucose also known as a aldohexose is a monosaccharide with 6 carbons and an aldehyde group. It has many forms and isomers and each one of them has its own importance and function. Glucose is known to be the most important carbohydrates partially because of its effects on functions of life. Glucose is essential for many causes such as photosynthesis, presence in blood sugar, major role in diabetes, manufacturing of candy and wine, and many other purposes. Glucose is a fundamental carbohydrate that we use in our daily lives and find in many different areas, which involve us.
Chemistry of Glucose
Glucose is a monosaccharide sugar or simple sugar made with a 6-carbon skeleton. It is a major energy source for animal and human metabolism, and provides a great structural role in cellulose. Glucose s chemical formula is C6H12O6, and it has many forms and is occurring widely in most plant and animal tissue. It is the main flowing sugar in the blood and the chief energy foundation of the body. It is known to be the most important monosaccharide.
The chemical formula C6H12O6 proves that glucose is a hexose because it shows that that the number of carbons it has is six. Glucose is a considered a monosaccharide because it cannot be broken down into additional fundamental components and still retain its sugar purpose. Glucose is sorted in the class of monosaccharide because its empirical formula, the formula that indicates the relative sizes of the elements in a molecule rather than the actual number of atoms of the elements, relates to the empirical formula of monosaccharides, (C1H12O1)n where n is the number of carbons found in the molecule.
Glucose contains an aldehyde group at Carbon 1 (H-C=O) so therefore it is called an aldohexose. Glucose consists of a 6-carbon chain with a C=O (a carbonyl group) attached to one of its ends. A carbonyl group contains a C=O bond inside the structure of a molecule, which in turn means that the carbon atom is double-bonded to the oxygen atom. If a molecules is know to have an aldehyde group, it means at either ends of the structure it has the formula of R-C=O. In the glucose molecule, R in the aldehyde group is a hydrogen atom. The prefix aldo- is placed before the root word of how many carbons the molecule contains if the molecule contains an aldehyde group. Glucose contains an aldehyde group at Carbon 1 (H-C=O), and it contains six carbons so therefore it is called an aldohexose.
Glucose has many compounds with same molecular formula, but different properties and structures, or isomers. Glucose is not the only molecule with the same molecular formula of C6H12O6. One type of isomer is a structural isomer, in which the number of atoms and the molecular formula stays the same, but the arrangement of the molecules differ. For example, a structural isomer of glucose is fructose which indeed keeps the same molecular formula as glucose, but whose structure differs. The difference between both compounds is that fructose has its carbonyl group in the inner carbon, and therefore called a ketohexose, while glucose has its carbonyl group at the end carbons calling it a aldohexose. Therefore, glucose and fructose are structural isomers of each other.
Another subclass of isomers is called stereoisomers. Stereoisomers is an isomer whose molecules have the same atoms bonded to each other and same formula, but differ in the way these atoms are arranged in space. Glucose and galactose are stereoisomers of the disasteomer subclass because they are both aldohexoses and they contain the same number of atoms in the same order from top to bottom. Although they obtain those similarities, the difference between both of them is that the second chiral carbon (C-3) in both molecules is mirror images of each other, basically saying that the molecules hydroxyl group and hydrogen molecule were reversed. Therefore, glucose and galactose are stereoisomers of each other. Since fructose is a ketohexose and does not have the same order in its straight chain projection it cannot be a stereoisomer of glucose or galactose.
Within the subclass of isomers to stereoisomers there are two are more subclasses, which are enantiomers and disasteomers. They are both stereoisomers, but the difference between them is that enantiomers are mirror images of each other, and disasteomers are not. Glucose also has two enantiomers and many other disasteomers. The complete number of stereoisomers of a molecule can be determined by a simple formula. The formula to find the amount is 2^X where X is the total number of chiral centers the molecule holds. In glucose s circumstance, there are four chiral centers (c-2 C-3, C-4, and C-5), and if one plugs 4 into 2^4 they attain 16. Thus, there are 16 stereoisomers both enantiomeric and disateomeric of glucose.
The two main isomers of glucose are called Dextrose & Levulose. These names are simplified to D and L Glucose. These two stereoisomers are categorized as enantiomers of each other, which means that the two structures are mirror images or asymmetric at the last chiral carbon (carbon with 4 distinctive groups attached to it). The carbons of a monosaccharide at the ends of the straight chain projection or the carbon that is in a carbonyl group can never be classified as chiral because they do not have 4 different groups attached to them. Dextrose or Dextroglucose, a stereoisomer of glucose, means that the absolute configuration at the asymmetric carbon furthest from the aldehyde or ketone group, namely C-5, is the same as in the D-glyceraldehyde. It is called dextrose or D-glucose, because it rotates the plane of polarization to the right and the hydroxyl group is to the right of the last chiral carbon. Levulose rotates the plane of polarization to the left and the hydroxyl group is to the left of the last chiral carbon. D-Glucose and L-Glucose differ in many cases. For instance, dextrose (D-glucose) is used by cells for food, but L-glucose is not. D and L glucoses are obtained by the inversion of sucrose (cane sugar), and therefore called invert sugar. Dextrose is essentially attained by the action of heat and acids on starch, and consequently called also starch sugar. It is also formed from starchy food by the action of the ferments of saliva and pancreatic juice. D-Glucose is further biologically active and a lot more abundant than L-glucose.
D and L Glucose can be easily determined if you look at the straight chain Fischer Projection, but determining whether or not a bottle filled with glucose is D or L is a different and a little more complicated procedure. You need a polarimeter to establish the chirality of an optically active solution (any crystal or molecule that can’t be superimposed on its mirror image or ability of a substance to rotate plane-polarized light) containing and enantiomeric monosaccharide. A D-Glucose solution will be rotated in the positive direction of +10 degrees, or right and the L-Glucose will be rotated to the negative direction or the left. Therefore there are two ways to decide on the chirality of glucose, either by inspection of the structure in Fischer Projection form or by experimentation using a polarimeter.
The principal forms of glucose in solution are not the open-chain structures (Fischer Projections), but rather the open-chain forms of glucose can cyclize to form rings. They form rings by adding one of their OH groups to the C=O on carbon 1 or Carbon 2. Glucose produces a ring of six atoms which are the first five carbons of the hexose chain and the oxygen from the OH that was on Carbon-5. The sixth carbon extends away from the ring connected to Carbon 5. We draw glucose in both straight chain forms and cyclic forms to determine the isomerism and arrangement of the molecule. In, general, an aldehyde can react with an alcohol to form hemiacetal.
Glucose can also be drawn in a Haworth projection, which can also be called the chair form. This projection is harder to draw and more complicated, but it is a lot accurate and accepted. This type of projection shows bond angles clearly and gives us a feel for the 3D nature of the molecule. The carbon atoms in the ring are not explicitly shown. The fairly accurate plane of the ring is perpendicular to the plane of the paper, with the heavy line on the ring nearest to the viewer.
When glucose cyclizes, an extra center is produced. Depending on the position of the C=O, d-glucose and l-glucose can be additionally categorized as alpha-d-glucose, beta-d-glucose, alpha-l-glucose, and beta-l-glucose. Carbon-1, the carbonyl carbon atom in the open chain form becomes an asymmetric center in the ring form. The position of the hydroxyl group at Carbon 1 on aldoses determines if the molecule is alpha or beta. For glucose, two ring configurations can be formed by this approach. These two are alpha D-glucose and Beta D glucose. The title alpha means that the hydroxyl group attached to C-1 is below the plane of the ring. Beta means that the hydroxyl group is above the plane of the ring.
Glucose is an essential molecule not only individually, but grouped with other sugars it forms many disaccharide, oligosaccharides and polysaccharides. An oligosaccharide is carbohydrate that contains 2-8 monosaccharides, while a disaccharide is a carbohydrate that that yields two monosaccharide molecules on complete hydrolysis.
There are many examples of carbohydrates on Earth that would not exist without the existence of glucose. For example, cellulose is formed from two beta-D-Glucose, but because the 1,4 B-O-glycosidic bond cannot be broken by your stomach you cannot eat wood! Lactose is disaccharide that is made partly from glucose. It contains beta-D-galactose and beta-D-glucose that are linked at carbons 1 and 4. Sucrose, the carbohydrate found in table sugar is made of alpha-D-glucose and beta-L-fructose bonded at 1,2-O-glycosidic acid. Maltose can also be formed using 2 alpha-d-glucoses or using alpha-D-glucose and beta-D-glucose. As you can see, glucose plays a major role in many other polysaccharides and carbohydrates as well as its individual use in society.
Glucose is produced by photosynthesis with the use of sunlight, carbon dioxide, and water.
The formula of photosynthesis: 6CO2 + 6H2O C6H12O6 + 6O2 with the use of sunlight. Photosynthesis is the process by which plants, some bacteria, and some protistas use the energy from sunlight, water, and carbon dioxide to produce sugar, which cellular respiration converts into ATP (adenosine triphosphate) a general figure in which energy is stored in all living things. One of the most general positions of photosynthesis is the organelle called chloroplast found in green plants. The membranes of chloroplast include a special pigment called chlorophyll. The change of impractical sunlight energy into practical chemical energy is related with the actions of the green pigment in the chlorophyll. The majority of the time, the photosynthetic process uses water and discharges the oxygen that we entirely must have to stay alive. The chlorophyll molecules confine energy from the protons in daylight. Glucose is a common hexose in plants. The products of photosynthesis are assembled to make glucose. Energy from sunlight is converted into the C-C covalent bond energy. This energy is released in living organisms in such a way that not enough heat is generated at once to burn the organisms. One mole of glucose yields 673 Kcal of energy. A calorie is the amount of heat needed to raise one gram of water 1 degree Celsius. A Kcal has 1000 times as much energy as a calorie.
Glucose is a white crystalline solid, less sweet than ordinary table sugar. It crystallizes in three dissimilar figures. The degree of rotation of polarized light is what makes one form differ from the other forms. Sucrose, ordinary table sugar is a disaccharide made from one D-glucose molecule and one L-fructose molecule combined. This mixture of glucose and fructose is called an invert sugar. Sucrose has many affects and functions in nature. It is found in sugar cane and sugar beets in high concentration. Only a very small portion of maple syrup is made from glucose and fructose, but 65% of it is made from sucrose.
Glucose is the chief sugar in blood and gives out tissues as the metabolic fuel. Its complete combustion is C6H12O6 + 6CO2 + 32* ADP + 32 P 6CO2 + 6H2O + 32* ATP + heat. This procedure necessitates glycolysis in the cytoplasm, and the citric acid cycle, electron transport and oxidative phosphorylation in the mitochondria. In some cells 34ATP are created.
Glucose is the principal sugar in animal blood. Because of the numerous hydroxyl groups sticking out from the molecule, it is soluble in the blood. These hydroxyl groups can hydrogen bond through water molecules, which in turn causes the molecule to be water-soluble. Glucose is found in ripe fruits, the nectar of flowers, leaves, saps and bloods and it is a variety of different names such as starch sugar, blood sugar, grape sugar, corn sugar and the obvious dextrose (for D-glucose).
Since glucose is extremely attracted to water molecules, it grasps water molecules to itself and develops syrup when concentrated. Corn syrup is a somewhat despoiled starch consisting of distinctive glucose molecules in addition to little chains of glucose molecules connected together. Because glucose molecules hold water rather closely, when a glucose solution is gradually dispersed, it develops into a syrup.
Many prokaryotic and eukaryotic cells use glucose as a major supply of energy. It is moderately oxidized to generate small packets of ATP by means of glycolysis in a lot of prokaryotes. It is totally oxidized by more advanced eukaryotic cells that have mitochondria.
Glucose is a significant factor of the blood and 5% mixture of D-glucose can offer nourishment to patients getting intravenous feeding. The molecule glucose has its blood concentration synchronized through the hormone insulin. Insulin is freed by the Islets of Langerhans in the pancreas. A flaw in the management system synchronized by insulin is identified as the disease diabetes mellitus.
There are two different ways that glucose is involved in the metabolism which is the sum of all the chemical reactions occurring in a cell, many of which are for breaking down nutrients, many of which are for building other molecules. The two classifications are anaerobic and aerobic. The anaerobic process, the process that does not need oxygen takes place in the cytoplasm of cells and is only somewhat resourceful. The aerobic cycle that occurs in the mitochondria of cells results in the maximum discharge of energy. Although it is more efficient, it requires oxygen.
Anaerobic glycolysis is the prolongation of glycolysis, where pyruvic acid molecules have their structure changed yet so slightly to produce lactic acid molecules that are responsible for the lactic acid burn. Glucose in the bloodstream diffuses into the cytoplasm and is kept there through phosphorylation, the addition of phosphates. A glucose molecule is then rearranged slightly. These steps really necessitate energy, in the form of two ATPs, adenosine triphosphate, which is a molecule that is high in energy, for each glucose. The fructose is then cut into generate two glyceraldehyde phosphates. Then the energy is finally released, in the form of two ATPs and two NADHs, as the GPs are oxidized to phosphoglycerates. One of the vital enzymes in this process is glyceraldehyde phosphate dehydrogenase (GPDH), which transfers a hydrogen atom from the GP to NAD to yield the NADH. Finally, two more ATPs are produced as the phosphoglycerates are oxidized to pyruvate.
The total reaction trace for the aerobic respiration of glucose is easily understandable. In the aerobic way, pyruvate (a salt of an ester of pyruvic acid) is the starting molecule for oxidative addition of phosphate groups by the means of the citric acid cycle. In this procedure all of the C C and C H bonds of the pyruvate will be shifted to oxygen. Essentially, the pyruvate is oxidized to acetyl coenzyme A, which can then combine with the four-carbon oxaloacetate to create a six-carbon citrate. Carbons and hydrogens are gradually cut from this citrate until all that remains is the four-carbon oxaloacetate (a salt or ester of oxalacetic acid) from the beginning. In this progression, four NADHs, one FADH and one GTP are generated for every one pyruvate.
The processes usually happen after glycolysis. Glycolysis is the breaking up of glucose into two smaller molecules called pyruvic acid. The sugar molecule goes through a sequence of several enzyme accelerated chemical reactions that literally split the six-carbon glucose sugar into three-carbon long pyruvic acid molecules. Glycolysis does not require oxygen and can proceed under both aerobic and anaerobic conditions. Although the glycolysis pathway contains ten distinct reactions, each of which is accelerated by a specific enzyme, it is divided into just two major phases. The first includes endergonic reactions that requires ATP, while the second includes exergonic reactions that produce ATP and NADH.
Overall glucose is a very resourceful and useful molecule, although it does play a major role in the disease diabetes. Glucose is found in many of the foods we eat, tanning, in dye baths, in creating medical products, and in medicine for treating dryness and for intravenous feeding. It acts as sweetener of foods as well as a lively ingredient in many dishes.
Glucose is used industrially to manufacture good such as alcohol and candy. It is formed by the action of enzymes in the bacterium Aspergillus oryzae, which breaks down starch molecules. This bacterium is also used to prepare rice starches for fermentation into ethanol in the production of the Japanese wine, Sake. Glucose is found in honey and the juices of many fruits and an substitute name for it is grape sugar which was derived from the presence of glucose in grapes.