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Which Of These Carbohydrates Is Made From Two Glucose Units Joined Together?

Carbohydrates

Carbohydrates

In many ways, our bodies can be thought of as chemical processing plants. Chemicals are taken in, processed through various types of reactions, and then distributed throughout the body to be used immediately or stored for later use. The chemicals used by the body can be divided into two broad categories: macronutrients, those substances that we need to eat regularly in fairly large quantities, and micronutrients, those substances that we need only in small amounts. Three major classes of macronutrients are essential to living organisms: carbohydrates, fats, and proteins. In this lesson, we will discuss the carbohydrates; fats and proteins are discussed in another lesson (see our Fats and Proteins module). Carbohydrates Carbohydrates are the main energy source for the human body. Chemically, carbohydrates are organic molecules in which carbon, hydrogen, and oxygen bond together in the ratio: Cx(H2O)y, where x and y are whole numbers that differ depending on the specific carbohydrate to which we are referring. Animals (including humans) break down carbohydrates during the process of metabolism to release energy. For example, the chemical metabolism of the sugar glucose is shown below: Animals obtain carbohydrates by eating foods that contain them, for example potatoes, rice, breads, and so on. These carbohydrates are manufactured by plants during the process of photosynthesis. Plants harvest energy from sunlight to run the reaction just described in reverse: A potato, for example, is primarily a chemical storage system containing glucose molecules manufactured during photosynthesis. In a potato, however, those glucose molecules are bound together in a long chain. As it turns out, there are two types of carbohydrates, the simple sugars and those carbohydrates that are made Continue reading >>

Disaccharides And Polysaccharides

Disaccharides And Polysaccharides

- [Voiceover] All right. In a previous video, I talked about how cyclic monosaccharides, like this green cyclic glucose, can react with alcohols, like this pink alcohol, to form acetals and ketals. I believe that I mentioned that sometimes the alcohol that comes in and is reduced is actually another carbohydrate. Let me draw this in here. It makes sense, because what you see, with carbohydrates, is that they're chock full of hydroxilate groups. They're chock full of these OH groups. So, really, they can function really similarly to alcohol in reactions. When this happens, the individual monosaccharides are linked together to make an acetal. We call this linkage a glycosidic linkage. This is a glycosidic, a glycosidic linkage. Now, when two monosaccharides are linked together in this fashion, by glycosidic linkages, we call the product a disaccharide. A disaccharide. We have "di," which means two, and "saccharide," which means sugar. So sugar. So two monosaccharides linked together, they're called a disaccharide. Now, with disaccharides, most commonly the glycosidic linkage forms between the anomaric carbon, or C1 ... Remember, this is the anomeric carbon. That's C1. Over in our glycosite here, it'd be right here, just the same, we got C1 of the first sugar. Then, C4 of the second sugar, so right here would be C4, and it's just the same over here. So right here we have C4. That's the second sugar. So we call this a one, four glycosidic linkage. Then, just like we could further break down our monosaccharides into alpha and beta based off the orientation of the anomeric hydroxyl group, we can more specifically call the one, four linkage an alpha or a beta linkage, again, based off what is now the orientation of the OR group on the anomeric carbon. Same rules apply. If the Continue reading >>

The Nutrition And Feeding Of Farmed Fish And Shrimp - A Training Manual 1. The Essential Nutrients

The Nutrition And Feeding Of Farmed Fish And Shrimp - A Training Manual 1. The Essential Nutrients

After the proteins and lipids, the carbohydrates represent the thirdmost abundant group of organic compounds in the animal body. By contrast,carbohydrates constitute the major class of organic nutrients within planttissues. The carbohydrate group includes such important compounds as glucose,fructose, sucrose, lactose, starch, glycogen, chitin, and cellulose. Carbohydrates are usually defined as substances containing carbon,hydrogen and oxygen, with the last two elements being present in the sameratio as in water (ie. Cx(H2O)y ). Although this definition is satisfactoryfor the majority of compounds present within this group, a few carbohydratescontain a lower proportion of oxygen than that in water or exist as carbohydratederivatives which may contain nitrogen and sulphur. The carbohydrates can be divided into two major groups according totheir chemical structure; the sugars and non-sugars (Table 8). The simplestsugars are called monosaccharides, and these inturn can be divided into fivesub-groups depending on the number of carbon atoms present in the molecule:Trioses (C3H6O3), Tetroses (C4H8O4), Pentoses (C5H10O5), and Hexoses (C6H12O6)These monosaccharides may also inturn be linked together (with the eliminationof water) to form di, tri or polysaccharides containing two, three or moremonosaccharide units or residues respectively. Here the term sugar isrestricted to those carbohydrates containing less than 10 monosaccharide units.Non-sugars are therefore carbohydrates which contain more than 10 monosaccharideunits and which do not possess a sweet taste. The non-sugars can be dividedinto two sub-groups, homopolysaccharides and heteropolysaccharides; the formerconsisting of identical monosaccharide units and the latter of mixtures ofdifferent monosaccharide units. In gen Continue reading >>

The Macromolecules

The Macromolecules

Polysaccharides are very large, high molecular weight biological molecules that are almost pure carbohydrate. They are constructed by animals and plants from simpler, monosaccharide molecules, by joining together large numbers of the simpler molecules using glycosidic bonds (-O-). In some of the largest polysaccarhide structures there can be 10,000 individual units joined together. There is a large diversity of polysaccharide form; they can differ in the type of sugar, the connections between the sugars and the complexity of the overall molecule. Sometimes known as glycans, there are three common and principal types of polysaccharide, cellulose, starch and glycogen, all made by joining together molecules of glucose in different ways. It has been estimated that 50% of the world's organic carbon is found in one molecule; cellulose. This molecule is synthesized, stored, modified and used as a building material by plants. It is certainly the most abundant of all the polysaccharides. In the cellulose molecule the individual glucose monosaccharides are all linked to one another in the form of a long, long, linear chain. The carbon atom number 1 (C1) in one sugar is linked to the fourth carbon atom (C4) of the next sugar in an extended array. All the glucose molecules in cellulose have the beta-configuration at the C1 atom, so all the glycosidic bonds that join the glucose molecules together are also of the beta type. This means that the cellulose molecule is straight, and many such molecules can lay side by side in a parallel series of rows. Tiny forces called hydrogen bonds hold the glucose molecules together, and the chains in close proximity. Although each hydrogen bond is very, very weak, when thousands or millions of them form between two cellulose molecules the result i Continue reading >>

Disaccharide | Biochemistry | Britannica.com

Disaccharide | Biochemistry | Britannica.com

Disaccharide, also called double sugar, any substance that is composed of two molecules of simple sugars ( monosaccharides ) linked to each other. Disaccharides are crystalline water-soluble compounds . The monosaccharides within them are linked by a glycosidic bond (or glycosidic linkage), the position of which may be designated - or - or a combination of the two (-,-). Glycosidic bonds are cleaved by enzymes known as glycosidases. The three major disaccharides are sucrose , lactose , and maltose. In the bacterium Escherichia coli, energy is derived from the metabolism of disaccharide and oligosaccharide sugars and other small molecules. Sucrose, which is formed following photosynthesis in green plants, consists of one molecule of glucose and one of fructose bonded via an -,-linkage. Lactose (milk sugar), found in the milk of all mammals , consists of glucose and galactose connected by a -linkage. Maltose , a product of the breakdown of starches during digestion, consists of two molecules of glucose connected via an -linkage. Another important disaccharide, trehalose , which is found in single-celled organisms and in many insects , also consists of two molecules of glucose and an -linkage, but the linkage is distinct from the one found in maltose. Continue reading >>

Ntrs 410: Chapter 7- Carbohydrates

Ntrs 410: Chapter 7- Carbohydrates

Polysaccharides, such as starch and cellulose. Saccharide with six carbon atoms, the most common size unit. Carbohydrate containing only one saccharide unit. Synonym for glucose; so named because polarized light bends to the right in a glucose solution. Synonym for fructose; so named because polarized light bends to the left in a fructose solution. Hexose with one carbon atom external to the 6-membered ring. Hexose with two carbon atoms external to the 5-membered ring. Carbohydrate formed by the union of two monosac charides with the elimina tion of a molecule of water. Carbohydrate formed by the union of three to ten monosaccharides joined by the elimination of water. Carbohydrate formed by the union of many saccharide units, with the elimination of a molecule of water at each point of linkage. Polysaccharides composed entirely of glucose units linked together and distin guishable from starch by a shorter chain length. Complex carbohydrates in bacteria and yeasts charac terized by 1,6-a-glucosidic linkages. Complex carbohydrate consisting of two fractionsamylose and amylopectinboth of which are polymers of glucose joined together by the elimination of water. Straight-chain, slightly solu ble starch fraction consisting of glucose units joined by 1,4-a-glucosidic linkages that were formed with the loss of a molecule of water. Branched fraction of starch consisting primarily of glucose units linked with 1,4-a-glucosidic linkages, but interrupted occasion ally with a 1,6 linkage resulting in a very large polysaccharide. Complex carbohydrate that serves as the storage form of carbohydrate in animals; glucose polymer with 1,4-a- glucosidic linkages inter rupted by 1,6 linkages about every 8-12 units, resulting in bulky branching. Complex carbohydrate composed of glucose uni Continue reading >>

What Are Simple Carbohydrates, Complex Carbohydrates, And Dietary Fiber?

What Are Simple Carbohydrates, Complex Carbohydrates, And Dietary Fiber?

Carbohydrates are a necessary part of a healthy diet, offering your body nutrients it can convert to glucose to power muscles. Carbohydrates come in three varieties: simple carbohydrates, complex carbohydrates, and dietary fiber. All are composed of units of sugar. What makes one carbohydrate different from another is the number of sugar units it contains and how the units are linked together. Simple carbohydrates: These carbohydrates have only one or two units of sugar. A carbohydrate with one unit of sugar is called a simple sugar or a monosaccharide (mono = one; saccharide = sugar). Fructose (fruit sugar) is a monosaccharide, and so are glucose (blood sugar), the sugar produced when you digest carbohydrates, and galactose, the sugar derived from digesting lactose (milk sugar). A carbohydrate with two units of sugar is called a double sugar or a disaccharide (di = two). Sucrose (table sugar), which is made of one unit of fructose and one unit of glucose, is a disaccharide. Complex carbohydrates: Also known as polysaccharides (poly = many), these carbs have more than two units of sugar linked together. Carbs with three to ten units of sugar are sometimes called oligosaccharides (oligo = few). Because complex carbohydrates are, well, complex, with anywhere from three to a zillion units of sugars, your body takes longer to digest them than it takes to digest simple carbohydrates. As a result, digesting complex carbohydrates releases glucose into your bloodstream more slowly and evenly than digesting simple carbs. Raffinose is a trisaccharide (tri = three) that’s found in potatoes, beans, and beets. It has one unit each of galactose, glucose, and fructose. Stachyose is a tetrasaccharide (tetra = four) found in the same vegetables mentioned in the previous item. It has o Continue reading >>

Carbohydrates | Microbiology

Carbohydrates | Microbiology

Give examples of monosaccharides and polysaccharides Describe the function of monosaccharides and polysaccharides within a cell The most abundant biomolecules on earth are carbohydrates. From a chemical viewpoint, carbohydrates are primarily a combination of carbon and water, and many of them have the empirical formula (CH2O)n, where n is the number of repeated units. This view represents these molecules simply as hydrated carbon atom chains in which water molecules attach to each carbon atom, leading to the term carbohydrates. Although all carbohydrates contain carbon, hydrogen, and oxygen, there are some that also contain nitrogen, phosphorus, and/or sulfur. Carbohydrates have myriad different functions. They are abundant in terrestrial ecosystems, many forms of which we use as food sources. These molecules are also vital parts of macromolecular structures that store and transmit genetic information (i.e., DNA and RNA). They are the basis of biological polymers that impart strength to various structural components of organisms (e.g., cellulose and chitin), and they are the primary source of energy storage in the form of starch and glycogen. In biochemistry, carbohydrates are often called saccharides, from the Greek sakcharon, meaning sugar, although not all the saccharides are sweet. The simplest carbohydrates are called monosaccharides, or simple sugars. They are the building blocks (monomers) for the synthesis of polymers or complex carbohydrates, as will be discussed further in this section. Monosaccharides are classified based on the number of carbons in the molecule. General categories are identified using a prefix that indicates the number of carbons and the suffix ose, which indicates a saccharide; for example, triose (three carbons), tetrose (four carbons), p Continue reading >>

Chapter 5 - Term Definition Simple Carbohydrates...

Chapter 5 - Term Definition Simple Carbohydrates...

This preview shows page 1 - 6 out of 16 pages. Term:simple carbohydratesDefinition:Monosaccharides and disaccharides. Sugars composed of a single sugarmolecule (a monosaccharide) or twojoined sugar molecules (adisaccharide).Term:monosaccharidesDefinition:Single sugar units. The common onesare glucose, fructose, and galactose.Term:disaccharidesDefinition:Carbohydrates composed of twomonosaccharide units chemicallylinked. They include sucrose (commontable sugar), lactose (milk sugar), andmaltose.Term:glucoseDefinition:A common monosaccharide that is acomponent of disaccharides (sucrose,lactose, and maltose) and variouscomplex carbohydrates; present in theblood. Also known as DEXTROSE. Term:fructoseDefinition:A common monosaccharide naturallypresent in honey and many fruits. Also called LEVULOSE or FRUITSUGAR.Term:galactoseDefinition:A monosaccharide that has a structuresimilar to glucose; usually joined withother monosaccharides.Term:sucroseDefinition:A disaccharide composed of onemolecule of glucose and one moleculeof fructose joined together. Alsoknown as TABLE SUGAR.Term:lactoseDefinition:A disaccharide composed of glucoseand galactose; also called MILKSUGAR because it is the major sugarin milk and dairy products. Term:maltoseDefinition:A disaccharide composed of twoglucose molecules; sometimes calledMALT SUGAR. Seldom occursnaturally in foods but is formedwhenever long molecules of starchbreak down.Term:complex carbohydratesDefinition:Chains of more than twomonosaccharides. May beoligosaccharides or polysaccharides.Term:oligosaccharidesDefinition:Short carbohydrate chains composedof 3 to 10 sugar molecules.Term:polysaccharidesDefinition:Long carbohydrate chains composedof more than 10 sugar molecules. Canbe straight or branched. Term:starchDefinition:The major storag Continue reading >>

Carbohydrate

Carbohydrate

Lactose is a disaccharide found in animal milk. It consists of a molecule of D-galactose and a molecule of D-glucose bonded by beta-1-4 glycosidic linkage. It has a formula of C12H22O11. A carbohydrate is a biological molecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water); in other words, with the empirical formula Cm(H2O)n (where m could be different from n).[1] This formula holds true for monosaccharides. Some exceptions exist; for example, deoxyribose, a sugar component of DNA,[2] has the empirical formula C5H10O4.[3] Carbohydrates are technically hydrates of carbon;[4] structurally it is more accurate to view them as polyhydroxy aldehydes and ketones.[5] The term is most common in biochemistry, where it is a synonym of 'saccharide', a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides and disaccharides, the smallest (lower molecular weight) carbohydrates, are commonly referred to as sugars.[6] The word saccharide comes from the Greek word σάκχαρον (sákkharon), meaning "sugar".[7] While the scientific nomenclature of carbohydrates is complex, the names of the monosaccharides and disaccharides very often end in the suffix -ose. For example, grape sugar is the monosaccharide glucose, cane sugar is the disaccharide sucrose, and milk sugar is the disaccharide lactose. Carbohydrates perform numerous roles in living organisms. Polysaccharides serve for the storage of energy (e.g. starch and glycogen) and as structural components (e.g. cellulose in plants and chitin in arthropods). The 5-carbon monosaccharide ribose is an important component of co Continue reading >>

Help Us Do More

Help Us Do More

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 (H​O). 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

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 >>

Biochemistry/carbohydrates

Biochemistry/carbohydrates

"Carbohydrates" are chemically defined as "polyhydroxy aldehyde or polyhydroxy ketones or complex substances which on hydrolysis yield polyhydroxy aldehyde or polyhydroxy ketone." Carbohydrates are one of the fundamental classes of macromolecules found in biology. Carbohydrates are commonly found in most organisms, and play important roles in organism structure, and are a primary energy source for animals and plants. Most carbohydrates are sugars or composed mainly of sugars. By far, the most common carbohydrate found in nature is glucose, which plays a major role in cellular respiration and photosynthesis. Some carbohydrates are for structural purposes, such as cellulose (which composes plants' cell walls) and chitin (a major component of insect exoskeletons). However, the majority of carbohydrates are used for energy purposes, especially in animals. Carbohydrates are made up of a 1:2:1 ratio of Carbon, Hydrogen, and Oxygen (CH2O)n These are used only for energy in living organisms. Simple carbohydrates are also known as "Monosaccharides".The chemical formula for all the monosaccharides is CnH2nOn. They are all structural isomers of each other. There are two main types of monosaccharides. The first type are aldoses, containing an aldehyde on the first carbon, and the second type are ketoses, which have a ketone on the second carbon (This carbonyl group is always located on the second carbon). Name Formula Aldoses Ketoses Trioses C3 H6 O3 Glycerose Dihydroxyacetone Tetroses C4 H8 O4 Erythrose Erythrulose Pentoses C5 H10 O5 Ribose Ribulose Hexoses C6 H12 O6 Glucose Fructose Heptose C7 H14 O7 Glucoheptose Sodoheptulose The suffix -oses is kept for the aldoses & the suffix -uloses is kept for the ketoses. Except fructose ketoses are as common as aldoses.The most abundant m Continue reading >>

Types Of Sugar

Types Of Sugar

There are several types of sugar. This page mentions some specific sugars but concentrates on the main categories of sugars (monosaccharides and disaccharides) and the relationship between these and certain larger carbohydrates. What is Sugar ? Definition of sugar : A sugar is a carbohydrate that is soluble in water. Sugars are usually crystalline and have a sweet taste. Chemicals that are sugars often have names ending in "-ose". For example, note the suffix "-ose" in fructose, glucose, galactose, sucrose, lactose, and maltose. The word-ending "-saccharide" does not necessarily indicate that the chemical or group or category of chemicals is a sugar. See more examples of prefixes and suffixes used in biology - general biology, not all medical terms. The two main categories of sugars are monosaccharides and disaccharides. They are often described together with polysaccharides, and sometimes also oligosaccarides, due to the chemical relationship between these types of carbohydrates: Categories of sugars: Monosaccharides are simple ("unit") sugars. Disaccharides consist of molecules whose form is that of two monosaccharide molecules joined together. Categories of larger carbohydrate molecules formed from sugars: Oligosaccharides consist of molecules formed from a few (i.e. more than 2, but not "many") monosaccharide molecules joined together. Polysaccharides consist of molecules formed from many monosaccharide molecules attached together in the form of long chains. Courses covering the human digestive system and human diet and nutrition often include the following information about: Monosaccharides Disaccharides Oligosaccharides, and Polysaccharides 1. Monosaccharides Chemical Structure: Monosaccharides are also called "simple sugars". Monosaccharides are the common base u Continue reading >>

Complex Carbohydrates Are Formed By Linkage Of Monosaccharides

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 >>

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