Carbohydrate Polymers | A Level Notes
Home > Biology > Biological Molecules > Biological Molecules > Carbohydrate polymers Carbohydrates are used in many different ways in an organism. Here polymers of Glucose that are involved in storage and structure are explored. Glucose units contain a lot of bonds that can be broken down to release energy during respiration to create ATP. The breakdown occurs in a series of steps which are driven by shape-specific Enzymes. In plants and animals, only glucose can be broken down in respiration as only the enzymes which fit its shape are present. Glucose can form long chains with thousands of subunits called and Amylose molecule. Glucose units are bonded together by Condensation Reactions forming (14) Glycosidic Bonds. Amylose molecules tend to form coiled springs due to the way in which the the glucose units bond, making it quite compact. Large molecules such as amylose differ from glucose in that they are not water soluable. Iodine molecules can become trapped within the 'coils' of the Amylose chain, which causes iodine (in Potassium Iodide solution) to change colour from yellow-brown to blue-black. Starch consists of a mixture of Amylose and a branched carbohydrate chain called Amylopectin. The branches are formed when a one end of a chain joins with a glucose in another, forming a (14) Glycosidic Bond. Glycogen is almost identical to starch but differs in that the chains of (14) linked glucoses are shorter, giving it a more highly branched structure. This branching allows for the fast breakdown of the molecule during respiration as it means that there are more ends which enzymes can start the proccess of hydrolysis from. Engergy storage molecules like Starch and Glycogen: are insoluble in water and so do not affect the water potential of cells. store glucose molecule Continue reading >>
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What’s in a spud? Besides water, which makes up most of the potato’s weight, there’s a little fat, a little protein…and a whole lot of carbohydrate (about 37 grams in a medium potato). Some of that carbohydrate is in the form of sugars. These provide the potato, and the person eating the potato, with a ready fuel source. A bit more of the potato's carbohydrate is in the form of fiber, including cellulose polymers that give structure to the potato’s cell walls. Most of the carbohydrate, though, is in the form of starch, long chains of linked glucose molecules that are a storage form of fuel. When you eat French fries, potato chips, or a baked potato with all the fixings, enzymes in your digestive tract get to work on the long glucose chains, breaking them down into smaller sugars that your cells can use. Carbohydrates are biological molecules made of carbon, hydrogen, and oxygen in a ratio of roughly one carbon atom (C) to one water molecule (HO). This composition gives carbohydrates their name: they are made up of carbon (carbo-) plus water (-hydrate). Carbohydrate chains come in different lengths, and biologically important carbohydrates belong to three categories: monosaccharides, disaccharides, and polysaccharides. In this article, we’ll learn more about each type of carbohydrates, as well as the essential energetic and structural roles they play in humans and other organisms. If the sugar has an aldehyde group, meaning that the carbonyl C is the last one in the chain, it is known as an aldose. If the carbonyl C is internal to the chain, so that there are other carbons on both sides of it, it forms a ketone group and the sugar is called a ketose. Sugars are also named according to their number of carbons: some of the most common types are trioses (thre Continue reading >>
Carbohydrates Flashcards | Quizlet
chains of 3+ monosaccharides (oligosaccharides or polysaccharides) short carbohydrate chanis of 3-10 molecules long carbohydrate chains of 11+ molecules. straight or branched major storage form of carbohydrates in plants. long chains of glucose in straight (amylose) or branching (amylopectin) arrangements straight chain polysaccharide composed of glucose units branched chain polysaccharide composed of glucose very large, highly branched polysaccharide composed of multi-glucose units. animal starch- primary storage of glucose in animals carbohydrates and lignin that are naturally present in plants and are nondigestable. not digested and absorbed by small intestine isolated nondigestable carbohydrates including some manufactured carbohydrates that have beneficial effects on humans straight chain polysaccharide compose of hundreds of glucose units linked by beta bonds. nondigestable and component of dietary fiber group of large polysaccharides in dietary fiber that are fermented more easily than cellulose dietary fibers that contain galactose and other monosaccharides, found between plant cell walls gel-forming dietary fibers containing galactose, maltose, and glucose. found in seaweed dietary fibers that are not carbohydrates. in broccoli and carrots branched polysaccharide chains of glucose found in barley and oats, help decreased blood cholesterol levels long chain structural polysaccharide of slightly modified glucose. found in hard exterior skeletons of insects, crustaceans, and other invertebrates. cell walls of fungi starch-digesting enzyme secreated by pancrease chemical bonds linked monosaccharides which can be broken by human intestinal enzymes, releasing monosaccharides. in starch, maltose, and sucrose chemical bonds linking monosaccharides which sometimes cann Continue reading >>
Biodotedu
The basic 'monomer' from which general hydrocarbons are constructed is a -[CH2]- unit. These are joined together in long, straight chains to form molecules such as octane. Hydrocarbons contain and store a lot of energy in their bonds, and are thus good fuel molecules (gasoline, for example contains a lot of hydrocarbons). However, they are strongly hydrophobic (they 'hate' water), so it is very difficult for living cells and organisms to manipulate and use pure hydrocarbons. About the only use for nearly pure hydrocarbons is wax, which is so strongly hydrophobic that it is used as a waterproofing material. Fatty acids consist of long, unbranched hydrocarbons with a carboxylic acid group at one end. The number of carbon atoms in a fatty acid molecule is usually even (6, 8, 12, 32, 36, etc.), although it is not impossible to find a fatty acid with an odd number of carbon atoms in its structure. While the long, hydrocarbon chain of the fatty acid continues to be strongly hydrophobic, the presence of the carboxylic acid group at one end of the molecule adds some hydrophilic properties. Small fatty acids such as propionic acid (with 3 carbon atoms) mixes with water readily, caproic acid (with 6 carbon atoms) is only 0.4 percent soluble in water. Typical animal fatty acids are palmitic (C16), and stearic (C18), which have hydrocarbon chains in which each carbon atom is also linked with two hydrogen atoms (-CH2-CH2-CH2-CH2-CH2-). These are called saturated fatty acids. Animals also contain fatty acids in which there are less hydrogen atoms joined to some of the carbon atoms, and a double bond between two carbon atoms takes their place. These are the unsaturated fatty acids, such as oleic acid (CH3-[CH2]7-CH==CH-[CH2]7-COOH), which is the most common fatty acid found in nature Continue reading >>
Glossary
The conversion ofcarbohydrates to alcohols, acids, and carbondioxide without the use of oxygen. Carbohydrates containingmany glucose units, from 10 to 1000 or more. A digestible straight-chain type ofstarch composed of glucose units. A digestible branched-chaintype of starch composed of glucose units. An insoluble straight-chainpolysaccharide made of glucose moleculesthat is undigestible. An insoluble fiber containingxylose, galactose, glucose, and othermonosaccharides bonded together. A soluble fiber containing chains ofgalacturonic acid and other monosaccharides;characteristically found between plant cellwalls. A soluble fiber containing chains ofgalactose, glucuronic acid, and othermonosaccharides; characteristically found inexudates from plant stems. A soluble fiber consisting ofchains of galactose, mannose, and othermonosaccharides; characteristically found inseaweed. An insoluble fiber made up of amultiringed alcohol (noncarbohydrate)structure. Grains containing the entireseed of the plant, including the bran, germ,and endosperm (starchy interior). Examplesare whole wheat and brown rice. Fiber added to foods thathas shown to provide health benefits. Combination of dietary fiber andfunctional fiber in a food. Also just called fiber. Starch-digesting enzyme from thesalivary glands or pancreas. An enzyme made by absorptive cellsof the small intestine; this enzyme digestsmaltose to two glucoses. An enzyme made by absorptive cellsof the small intestine; this enzyme digestssucrose to glucose and fructose. An enzyme made by absorptive cellsof the small intestine; this enzyme digestslactose to glucose and galactose. Products of incompletebreakdown of fat containing three or fourcarbons. The condition of having a highconcentration of ketone bodies and relatedbreakdown pro Continue reading >>
Why Is Ribose Not A Dietary Consideration
Carbohydrates Structures and Function Simple sugars: monosaccharides, disaccharides, oligosaccharides) Complex sugar: polysaccharides (starch and fiber) Monosaccharides (glucose, fructose, and galactose – isomers of each other) Glucose (also called dextrose and blood sugar) has a six carbon (hexose) ring structure Fructose (also called levulose) has a six carbon ring structure Found in fruit, honey, and corn syrup used in soft drink and food production 8 to 10% of our energy intake Metabolized into glucose in the liver Converted into glycogen, lactic acid, or fat if consumption is high Galactose has a six carbon ring structure Not usually found in nature but exists mostly as a unit of the disaccharide lactose which is found in nature Converted to glucose in the liver or stored as glycogen Ribose has a five carbon ring structure and used in genetic material (?) Oligosaccharides Raffinose (trisaccharide - made up of glucose, fructose, and galactose) Stachyose (tetrasaccharide - made up of a glucose, fructose, and two galactose) Bacteria in the large intestines break apart these oligosaccharides, producing gas and other byproducts Complex Cabohydrates (Digestible starch and glycogen and indigestible fiber) Starch Amylose is a straight chain polymer Amylopectin is a branched chain polymer Amylopectin raises blood sugar levels quicker because of the branched configuration which enables more digestive capabilities Fiber Dietary fibers also composed of the non-carbohydrate called lignin All dietary fibers come from plants and are not digested in the stomach But fibers can be soluble and insoluble in water Those that are soluble include pectins, gums, and mucilages and are metabolized by bacteria in the intestines Carbohydrate Digestion and Absorption Begins in the mouth (sal Continue reading >>
Monosaccharides - An Overview | Sciencedirect Topics
Monosaccharides are single polyhydroxyaldehyde (e.g., glucose) or polyhydroxyketone units (e.g., fructose), whereas oligosaccharides consist of 210 monosaccharide units joined together by glycosidic linkages. Larry R. Engelking, in Textbook of Veterinary Physiological Chemistry (Third Edition) , 2015 Monosaccharides (largely hexoses and pentoses) require no intestinal digestion prior to absorption; however, oligosaccharides must be hydrolyzed to monosaccharides before they can be absorbed. Since mammals lack the enzyme cellulase, they are incapable of carrying out the constitutive digestion of cellulose (which contains -1,4 glycosidic linkages). However, they can digest (i.e., hydrolyze) dietary starch and glycogen (which contain -1,4 and -1,6 glycosidic linkages). Sites for starch and glycogen digestion are in the mouth and upper small intestine. Most monosaccharide absorption occurs in the duodenum and jejunum. Elaine M Aldred BSc (Hons), DC, Lic Ac, Dip Herb Med, Dip CHM, ... Kenneth Vall, in Pharmacology , 2009 Monosaccharides can join together by condensation (see Figure 4.7B, p. 26). When sugars are linked together the links can be one of two sorts: either at the fourth carbon (14 bond) or the sixth carbon (16 bond). The bonds created between individual sugars can vary between the 1, 4 or 6 carbon atoms on each monosaccharide. This will lead to combinations that result in different chemical and physical properties (as shown in Figure 9.7). Simple carbohydrates: one to three units of sugar linked together. Oligosaccharides: carbohydrates made up of two to ten monosaccharides. Monosaccharide is a generic term that includes compounds with the general formula (CH2O)n, where n = 3 to 8. Both aldoses and ketoses are included in this group and are distinguished by the p Continue reading >>
Plant Life: Carbohydrates
Common organic chemicals found in all living organisms, important in energy metabolism and structural polymers, carbohydrate molecules are made up of carbon, hydrogen, and oxygen. Carbohydrates are made of carbon, hydrogen, and oxygen molecules in a 1:2:1 ratio, respectively. This is often simplified using the formula nCH2O, where n represents the number of CH2O subunits in a carbohydrate. This formula should make it clear how the name carbohydrate was derived, as nCH2O is essentially carbon and water . The simplest carbohydrates are the monosaccharides , or simple sugars. Individual monosaccharides can be joined together to make disaccharides (composed of two monosaccharides), oligosaccharides (short polymers composed of two to several monosaccharides), and polysaccharides (longer polymers composed of numerous monosaccharides). The common monosaccharides found in plants have from three to six carbon atoms in a straight chain with one oxygen atom. Most of the oxygen atoms also have a hydrogen atom attached, making them hydroxyl groups (OH). One of the oxygen atoms is connected to a carbon by a double covalent bond, while the hydroxyl groups are attached to carbon atoms by single covalent bonds. If the double-bonded oxygen is on a terminal carbon (as an aldehyde group), the monosaccharide is called an aldose. If the double-bonded oxygen is on an internal carbon, the monosaccharide is called a ketose. The simplest monosaccharides are the three carbon sugars, or trioses. Pentoses, with five carbons, are also important in plants. Ribose and deoxyribose are found in RNA(ribonucleic acid) and DNA(deoxyribonucleic acid), respectively. Ribulose bisphosphate is an important intermediate in the incorporation of carbon dioxide into carbohydrates during photosynthesis . Xylose and Continue reading >>
Carbohydrates
Carbohydrates (also called saccharides) are molecular compounds made from just three elements: carbon, hydrogen and oxygen. Monosaccharides (e.g. glucose) and disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars. Other carbohydrate molecules are very large (polysaccharides such as starch and cellulose). Carbohydrates are: a source of energy for the body e.g. glucose and a store of energy, e.g. starch in plants building blocks for polysaccharides (giant carbohydrates), e.g. cellulose in plants and glycogen in the human body components of other molecules eg DNA, RNA, glycolipids, glycoproteins, ATP Monosaccharides Monosaccharides are the simplest carbohydrates and are often called single sugars. They are the building blocks from which all bigger carbohydrates are made. Monosaccharides have the general molecular formula (CH2O)n, where n can be 3, 5 or 6. They can be classified according to the number of carbon atoms in a molecule: n = 3 trioses, e.g. glyceraldehyde n = 5 pentoses, e.g. ribose and deoxyribose ('pent' indicates 5) n = 6 hexoses, e.g. fructose, glucose and galactose ('hex' indicates 6) There is more than one molecule with the molecular formula C5H10O5 and more than one with the molecular formula C6H12O6. Molecules that have the same molecular formula but different structural formulae are called structural isomers. Glyceraldehyde's molecular formula is C3H6O3. Its structural formula shows it contains an aldehyde group (-CHO) and two hydroxyl groups (-OH). The presence of an aldehyde group means that glyceraldehyde can also be classified as an aldose. It is a reducing sugar and gives a positive test with Benedict's reagent. CH2OHCH(OH)CHO is oxidised by Benedict's reagent to CH2OHCH(OH)COOH; the aldehyde group is oxidised to Continue reading >>
Difference Between Cellulose, Starch And Glycogen
Difference Between Cellulose, Starch and Glycogen These three polysaccharides differ in their glycosidic linkages and their functions too. Starting from the cellulose which is the monomer of beta glucose and is found in plant cell wall only. While Starch and Glycogen act as the carbohydrate reserve in plants and animals respectively. Though their chains have slight differences at the branching point, which is described below. We all are aware of the importance of carbohydrate, whether it is plants, animals (including humans), or microorganisms. It is the most abundantly found organic substances and has the significant value, as it acts as the dietary source and also serves as the structural component, provides energy. Carbohydrates are further classified as the monosaccharide, disaccharide, and polysaccharide. This classification is on the number of glucose or sugar units linked to each other. With this, we will be discussing the difference between the three main polysaccharides, which marks their presence adequately wherever needed or required. Cellulose is solely found in the plant only and is absent in vertebrates. In plants, it acts as the structural component and is present in the cell wall, especially in trunks, the woody area of the plants. Cellulose is the polysaccharide and is made up of numerous glucose units linking together forming the long chain. The linking of the glucose unit or the glycosidic bond is of (1-4). The chain is unbranched, linear containing 10,000 to 15,000 D-glucose units. The above statement is important to notice as this is the only reason that human cannot digest (hydrolyze) cellulose, as the enzyme which is needed to the break the beta-glycosidic linkage is absent in humans. Though certain ruminating animals have the microorganisms in t Continue reading >>
Organic Compound #1: Carbohydrates
Carbohydrates are sugars. Sugars are carbohydrates. Saccharide means sugar. We commonly divide carbs into three classes: 2. Disaccharides (made of two single sugars, snapped together) 3. Polysaccharides (many sugars snapped together) Theres hundreds of types of these but were going to go over just a few examples of each. The first two examples are 5-carbon atoms long: Ribose and Deoxyribose. Ribose is found in RNA. Deoxyribose is found in DNA. A deoxyribose is missing one oxygen, which is why its called de-oxy. The next three examples are 6-carbon atoms long: Glucose, Fructose and Galactose. Whats interesting about these are that all three of them are 6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms. The molecular formula for all three of them is C6H12O6 So wait a second If all three of them are C6H12O6, why are they different? They are isomers. The term we use when the atoms are the same molecular formula but arranged differently are chemical isomers. Isomer literally means same type but they are not identical. These three monosaccharides above are all C6H12O6 but clearly arranged differently. These three monosaccharides are mostly used as sources of energy by living cells, including ours. Whats also shown above is that these sugars are not a straight chain of carbon atoms. They are actually looped together as a ring-shape. This is known as a cyclic shape which refers to the ring shape. When you see pictures that look like this, recognize them as sugars. Three examples of Disaccharides (double sugars) 1. Sucrose aka cane sugar is made of glucose + fructose snapping together to form a disaccharide. Hydrogen from one and an OH from another are removed and thats where they attach together and water is produced as a result. The name for this type of reaction is a dehy Continue reading >>
Amylopectin | Chemistry | Britannica.com
THIS IS A DIRECTORY PAGE. Britannica does not currently have an article on this topic. Learn about this topic in these articles: of two components: amylose and amylopectin. The relative proportion of these two components varies, and they react differently to enzymatic attack. The enzyme -amylase (maltogenic) attacks the straight chain amylose but is unable to attack most of the branch chain amylopectin. If only -amylase is present, maltose is produced, together and a branched component (amylopectin). The use of starch as an energy source by humans depends on the ability to convert it completely to individual glucose units; the process is initiated by the action of enzymes called amylases, synthesized by the salivary glands in the mouth, and continues in the form of amylose or amylopectin. These starches are polysaccharides in which the monomer, or fundamental unit, is glucose. Green algal starch comprises more than 1,000 sugar molecules, joined by alpha linkages between the number 1 and number 4 carbon atoms. The cell walls of many, but not all, algae of two components: amylose and amylopectin. The glucose molecules composing amylose have a straight-chain, or linear, structure. Amylopectin has a branched-chain structure and is a somewhat more compact molecule. Several thousand glucose units may be present in a single starch molecule. (In the diagram, each small circle represents one glucose Continue reading >>
Complex Carbohydrates Are Formed By Linkage Of Monosaccharides
Because sugars contain many hydroxyl groups, glycosidic bonds can join one monosaccharide to another. Oligosaccharides are built by the linkage of two or more monosaccharides by O-glycosidic bonds (Figure 11.10). In maltose, for example, two d-glucose residues are joined by a glycosidic linkage between the α-anomeric form of C-1 on one sugar and the hydroxyl oxygen atom on C-4 of the adjacent sugar. Such a linkage is called an α-1,4-glycosidic bond. The fact that monosaccharides have multiple hydroxyl groups means that various glycosidic linkages are possible. Indeed, the wide array of these linkages in concert with the wide variety of monosaccharides and their many isomeric forms makes complex carbohydrates information-rich molecules. Go to: 11.2.1. Sucrose, Lactose, and Maltose Are the Common Disaccharides A disaccharide consists of two sugars joined by an O-glycosidic bond. Three abundant disaccharides are sucrose, lactose, and maltose (Figure 11.11). Sucrose (common table sugar) is obtained commercially from cane or beet. The anomeric carbon atoms of a glucose unit and a fructose unit are joined in this disaccharide; the configuration of this glycosidic linkage is α for glucose and β for fructose. Sucrose can be cleaved into its component monosaccharides by the enzyme sucrase. Lactose, the disaccharide of milk, consists of galactose joined to glucose by a β-1,4-glycosidic linkage. Lactose is hydrolyzed to these monosaccharides by lactase in human beings (Section 16.1.12) and by β-galactosidase in bacteria. In maltose, two glucose units are joined by an α-1,4 glycosidic linkage, as stated earlier. Maltose comes from the hydrolysis of starch and is in turn hydrolyzed to glucose by maltase. Sucrase, lactase, and maltase are located on the outer surfaces of epith Continue reading >>
Ch. 5 Carbohydrates Flashcards | Quizlet
Single sugar units . They are glucose, fructose and galactose. Carbohydrates composed of two monosaccharide units chemically linked. They include sucrose, lactose and maltose. A common monosaccharide that is a component of disaccharides and various complex carbohydrates; present in blood. Also known as dextrose. A common monosaccharide naturally present in honey and many fruits. Also called levulose or fruit sugar. A monosaccharide that has a structure similar to glucose; usually joined with other monosaccharides. A disaccharide composed of one molecule of glucose and one molecule of fructose joined together. Also known as table sugar. A disaccharide composed of glucose and galactose; also called milk sugar because it is a major sugar in milk and dairy products. A disaccharide composed of 2 glucose molecules; sometimes called malt sugar. Seldom occurs naturally in foods but is formed whenever long molecules of starch break down. Chains of more than two monosaccharides. May be oligosaccharides or polysaccharides. Short carbohydrate chains composed of 3-10 sugar molecules. Long carbohydrate chains composed of more than 10 sugar molecules. They can be straight or branched. The major storage form of carbohydrate in plants, it is composed of long chains of glucose molecules in a straight or branching arrangement. A straight chain polysaccaride composed of glucose units. A branched chain polysaccharide composed of glucose units. A very large, highly branched polysaccharide composed of multiple glucose units. Sometimes called animal starch, it is primary storage form of glucose in animals. Carbohydrates and lignins that are naturally in plants and are nondigestible; they arent digested and absorbed in the human small intestine. Isolated non digestible carbohydrates, including Continue reading >>
Biology Unit #2 Flashcards | Quizlet
Why are carbon atoms so common in living things? One of the most abundant hydrocarbons in natural gass? 4 groups that are functional and organic? Hydroxyl, Carbonyl, Carboxyl, Amino group 3 shapes the carbon backbones of organic molecules can take? What determines the properties of a functional group? The carbon skeleton and the attached functional group Using the dehydration reaction, cells construct what from 2 monosaccharides? How meany monomers are polymers built from? What 4 classes are life's largest molecules classified into? Carbohydrates, lipids, proteins, nucleic acids Each time a monomer is added to a chain, what is released? How do cells break bonds between monomers? What's the connection between monomers and polymers? Many monomers linked together make polymers What molecule is released during the construction of a polymer? What is this reaction called? What are two things that carbohydrates provide? What's at the core of most sugar molecules found in nature? What molecule is the main fuel supply for cellular work? What happens to glucose molecules that are not used immediately? Incorporated into larger carbohydrates, used to make fat molecules A glucose molecule linked to a fructose molecule Long polymer chains made up of simple sugar monomers A polysaccharide found in plant cells that consists entirely of glucose monomers What happens when plants break down starch molecules? How do animals and humans store excess sugar? In the form of a polysaccharide called glycogen What polysaccharide in plants serve as building materials? What benefit does plants get from cellulose? Protects cells, stiffens plant preventing it from flopping over Why are almost all carbohydrates hydrophilic? What's the difference between a monosaccharide and a polysaccharide? A monosac Continue reading >>
