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Which Statement Is Correct About Glucose And Galactose

What Is The Difference Between Glucose And Galactose?

What Is The Difference Between Glucose And Galactose?

What is the Difference Between Glucose and Galactose? Teo Quay is a health communication enthusiast based in Ottawa, Canada. She has been studying, teaching and working in the fields of exercise physiology and nutrition since 2007. Teo received a master's degree in human nutrition from the University of British Columbia. Glucose is found naturally in honey and other sweeteners.Photo Credit: rvbox/iStock/Getty Images Glucose and galactose are sugars made of a single sugar unit, also referred to as monosaccharides. They are found naturally in the food supply, or they result from the digestion of larger chains of sugar units in the human gastrointestinal tract. Glucose is the main sugar in the bloodstream and is also the form that our body stores in chains called glycogen. It is used to fuel daily activity and exercise. Glucose and galactose are both simple structures made of a six-carbon ring. They are almost identical, but galactose differs slightly in the orientation of functional groups around the fourth carbon. Galactose has a higher melting point than glucose as a result of the structural differences. The main difference between these two sugars from a sensory perspective is that glucose is substantially sweeter, though neither is as sweet as table sugar. Very few foods naturally contain glucose and galactose, with the exception of sweeteners like honey. However, longer chains of carbohydrates that contain glucose and galactose are very common in the food supply. The main sources of glucose are fruits and dried fruit such as raisins and apricots; fruit juices; and sweeteners like honey. The main source of galactose is foods containing lactose, such as dairy products, though it does occur naturally in honey and beets. Lactose is broken down to generate galactose and Continue reading >>

Carbohydrates Flashcards | Quizlet

Carbohydrates Flashcards | Quizlet

Which of the following is not a monosaccharide? Which of the following is a disaccharide? Lactose is composed of the following two mono-saccharides: A. High-fructose corn syrup consists of glucose and fructose B. Invert sugar is produced by enzymatic cleavage of sucrose into glucose and galactose A. After digestion, sucrose and HFCS present in US soft drinks provide similar amounts of fructose B. Starch is built up solely from glucose units A. Guar gum is part of the hemicelluloses Which type of carbohydrate can be found in a steak? Which of the following foods has the highest carbohydrate content per 100 grams? Which of the following foods has the lowest carbohydrate content per 100 grams? Which of the following foods has the highest fiber content per 100 grams? Which of the following foods has the lowest fiber content per 100 grams? A. Brown sugar contains substantial amounts of fiber B. Peeling an apple removes all of the dietary fiber The following fiber is added to foods as a thickening agent: Which of the following foods is a source of resistant starch? Look up the amount of carbohydrates in the following foods and select the sequence that shows the proper ranking of foods from high to low carbohydrate content (per 100 grams) ? Look up the amount of carbohydrates in the following foods and select 4 items which contain approximately the same amount of carbohydrate (per 100 grams): potato, banana, grape juice, pasta (boiled) Which of the following is not an enzyme involved in carbohydrate digestion ? What statement about carbohydrate absorption is FALSE? carbohydrate absorption occurs mainly in the colon The enzymes required for the full digestion of starch to glucose are: The products of carbohydrate digestion are: Which statement about glycogen is correct: it is Continue reading >>

Biochem - Chapter 16 [carbohydrates]

Biochem - Chapter 16 [carbohydrates]

A. are representations of the cyclic form of sugars B. can show the distinction between the a and b anomers A. are representations of the cyclic form of sugars B. can show the distinction between the a and b anomers Which of the following is not a function of carbohydrates? B. They play key roles in processes that take place on the surface of cells. D. They are catalytic components of enzymes. D. They are catalytic components of enzymes. How many carbon atoms are in the simplest carbohydrates? Aldoses can form which type of cyclic structure? A. has one more chiral center (the anomeric carbon) than the open-chain form. B. loses a chiral center compared to the open-chain form. D. has one more carbon atom than the open-chain form. E. has one less carbon atom than the open-chain form. A. has one more chiral center (the anomeric carbon) than the open-chain form. Refer to Exhibit 16A. The enantiomer of D-glucose is: A. contains a five-membered ring as part of its cyclic structure. B. contains a six-membered ring as part of its cyclic structure. B. contains a six-membered ring as part of its cyclic structure. A. contains a five-membered ring as part of its cyclic structure. B. contains a six-membered ring as part of its cyclic structure. A. contains a five-membered ring as part of its cyclic structure. For a D-sugar, any group that is written to the right of the carbon in a Fischer projection A. has an upward projection in a Haworth projection. B. has a downward projection in a Haworth projection. C. may be either up or down in a Haworth projection, it depends on the individual sugar. B. has a downward projection in a Haworth projection. Which of the following groups is produced when an aldehyde is oxidized? A. always link to the other molecule through an oxygen atom. B. alwa Continue reading >>

What Is The Difference Between Glucose And Galactose? - Quora

What Is The Difference Between Glucose And Galactose? - Quora

What is the difference between glucose and galactose? Answered Apr 23, 2016 Author has 2.3k answers and 3.2m answer views Both are monosaccharides. Glucose is the main sugar metabolized by the body for energy. Galactose is less common in nature, but glucose and galactose combine to form lactose, milk sugar. Galactose is converted to glucose in the liver to be used as energy. Galactose is identical to glucose except for one hydroxyl group on carbon atom number four of the six-sided sugar. (Reference: Carbohydrates: Types of Carbohydrates) 18k Views View Upvoters Not for Reproduction If you mean structurally, Yit Chin Chuan and other have answered perfectly. However, if you mean the difference in term of metabolism, I will try to answer it: First, Glucose is sweeter than Galactose. As well, Glucose is a ready form for our body to metabolize. The same cannot be said about galactose. It has to be converted to glucose first through the leloir pathway. There is actually a disease related to galactose called galatosemia. It is the result of abnormalities in the leloir pathway. 20.7k Views View Upvoters Not for Reproduction Answered Oct 28, 2016 Author has 2.6k answers and 2.2m answer views There are several differences: Occurrence, Physical and chemical properties, Biological functional properties, Metabolism and end products formation, Genetic control in synthesis and biological functions, etc. For such a diverse differences, you would be in much better position to consults a biochemistry book to start with. One main structural difference is the positions of -OH groups on the C-skeleton, specially in C 3 and C 4 positions. In an one dimensional structures: in Glucose it is in Left handed on C 3, but in galactose it is Left handed in both C 3 and C 4 positions. 5.6k Views Not Continue reading >>

Monosaccharides Glucose Fructose Galactose

Monosaccharides Glucose Fructose Galactose

Monosaccharides are the simplest carbohydrates and are classified according to whether they are aldehyde or ketone derivatives, as well as the number of atoms contained in the molecule. Single hexoses, glucose and galactose require no digestion and can be absorbed directly into the bloodstream. Hexoses contain six carbon atoms, and are found in foods, while pentoses, ribose and deoxyribose contain five carbon atoms and are produced during the metabolism of foodstuffs. Three common sugars—glucose, galactose, and fructose, share the same molecular formula: C6H12O6. Because of their six carbon atoms, each is a hexose. Although all three share the same molecular formula, the arrangement of atoms differs in each case. Substances such as these three, which have identical molecular formulas but different structural formulas, are known as structural isomers. "Blood sugar" is the immediate source of energy for cellular respiration. Glucose, which is also referred to as dextrose, is a moderately sweet sugar found in vegetables and fruit. When glucose is fermented by the enzyme zymase, in yeast, it results in the formation of carbon dioxide and ethyl alcohol. It is the basic structure to which all carbohydrates are reduced to in the end, for transport via the bloodstream and use by the cells of the body. Two different pathways are involved in the metabolism of glucose: one anaerobic and one aerobic. The anaerobic process occurs in the cytoplasm and is only moderately efficient. The aerobic cycle takes place in the mitochondria and results in the greatest release of energy. As the name implies, though, it requires oxygen. Galactose is not normally found in nature, but is mostly hydrolyzed from the disaccharide lactose, which is found in milk, as part of a disaccharide made by Continue reading >>

What Is Galactose?

What Is Galactose?

Galactose is a simple sugar, which belongs to simple carbohydrates. Galactose is composed of the same elements as glucose, but has a different arrangement of atoms. Name origin: From the Greek gala = milk, and -ose, which denotes sugar. Galactose Formula Picture 1. Galactose vs glucose structure Nutrition Facts for Galactose Calories per gram = 4.1 Glycemic index (GI) = ? Sweetness relative to sucrose = 30% Net carbohydrates = 100% Is galactose an essential nutrient? Galactose is not an essential nutrient, which means you do not need to get it from food to be healthy; galactose can be synthesized in the human body from glucose. Galactose Functions in the Human Body In the human body, most of the ingested galactose is converted to glucose, which can provide 4.1 kilocalories per gram of energy, which is about the same as sucrose [1]. Galactose can bind to glucose to make lactose (in breast milk), to lipids to make glycolipids (for example, molecules that constitute blood groups A, B and AB), or to proteins to make glycoproteins (for example, in cell membranes). Galactose Sources The main dietary source of galactose is lactose from milk and yogurt, which is digested to galactose and glucose [2,3]. Foods containing small amounts of free galactose include low-lactose or lactose-free milk, certain yogurts, cheeses, creams, ice creams and other foods artificially sweetened with galactose [4]. Plain natural foods (fruits, vegetables, nuts, grains, fresh meats, eggs, milk) usually contain less than 0.3 g galactose per serving [4]. Certain medications may contain galactose as a filler. Galactose Absorption Galactose is absorbed in the small intestine by the same mechanism as glucose, that is by the help of SGLT-1 and GLUT-2 transport proteins in the small intestinal lining [6]. I Continue reading >>

Oxford University Press | Online Resource Centre | Multiple Choice Questions

Oxford University Press | Online Resource Centre | Multiple Choice Questions

Snape & Papachristodoulou: Biochemistry and Molecular Biology 5e Answer the following questions and then press 'Submit' to get your score. Which of the following statements about glycogen breakdown is correct? a) Glycogen phosphorylase hydrolyses glucose from the reducing end of a glycogen chain. b) Glucose-6-phosphatase is present in liver but not in muscle. c) Glucose-6-phosphatase is present in muscle but not in liver. d) Glycogen phosphorylase splits off glucose from the nonreducing end of a glycogen chain. Which of the following statements about glycogen synthesis is correct? a) Glycogen synthesis occurs at the reducing end of glycogen chains. b) Phosphoglucomutase drives glycogen synthesis because the reaction has a large negative c) Glycogen synthesis occurs when there is a high insulin to glucagon ratio. d) Glycogen synthesis occurs when there is a high glucagon to insulin ratio. Which of the following statements about galactose is correct? a) Galactose cannot be metabolised and remains in our blood after we consume milk. b) Galactose is a glucose epimer that can be used as a substrate by the enzymes that use glucose as a substrate. c) Galactose and fructose are isomers of glucose and can easily be interconverted. d) Galactosaemia is a serious genetic disease that requires the removal of galactose from the diet of newborn infants. Which of the following statements about the enzymes, glucokinase and/or hexokinase is correct? a) Glucokinase has a high affinity for glucose. b) Hexokinase has a high affinity for glucose. c) Hexokinase has a higher Km for glucose than has glucokinase. d) Glucokinase has a lower Km for glucose than has hexokinase. Which of the following statements about circulating lipoproteins is correct? a) Chylomicrons release cholesterol to adipo Continue reading >>

Why Is Ribose Not A Dietary Consideration

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 >>

Oxford University Press | Online Resource Centre | Chapter 10

Oxford University Press | Online Resource Centre | Chapter 10

Which of the following statements about glycogen breakdown is correct? a) Glycogen phosphorylase splits off glucose from the reducing end of a glycogen chain. b) Glucose-6-phosphatase is present in liver but not in muscle. c) Glucose-6-phosphatase is present in muscle but not in liver. d) Glycogen phosphorylase splits off glucose from the nonreducing end of a glycogen chain. Which of the following statements about glycogen synthesis is correct? a) Glycogen synthesis occurs at the reducing end of glycogen chains. b) Phosphoglucomutase drives glycogen synthesis because the reaction has a large negative G0,. c) Glycogen synthesis occurs when there is a high insulin to glucagon ratio d) Glycogen synthesis occurs when there is a high glucagon to insulin ratio. Which of the following statements about galactose is correct? a) Galactose cannot be metabolised and remains in our blood after we consume milk. b) Galactose is a glucose epimer that can be used as a substrate by the enzymes that use glucose as a substrate. c) Galactose and fructose are isomers of glucose and can easily be interconverted. d) Galactosaemia is a serious genetic disease that requires the removal of galactose from the diet of newborn infants. Which of the following statements about the enzymes, glucokinase and/or hexokinase is correct? a) Glucokinase has a high affinity for glucose. b) Hexokinase has a high affinity for glucose. c) Hexokinase has a higher Km for glucose than has glucokinase. d) Glucokinase has a lower Km for glucose than has hexokinase. Continue reading >>

Carbohydrates

Carbohydrates

Sort All of the following are correct about applying the glycemic index EXCEPT: a. results vary with the time of day. b. research results confirm the benefits of diabetics applying glycemic index principles. c. food factors may change glycemic index results. d. people's glycemic responses to food vary widely Research results concerning diabetes and the glycemic index are mixed, and no conclusions can be drawn at this time. See page 129 All of the following are warning signs of diabetes EXCEPT: a. drowsiness. b. itching. c. frequent infections of the skin, gums, vagina, or urinary tract. d. reduced urination. reduced urination Scientific studies have consistently demonstrated that increased blood insulin levels cause excess body fatness and obesity. a. True b. False False. Although insulin disturbances may trigger weight gain, this scientific truth remains: insulin can only assist in the storage of body fat when calories taken in are in excess of need. See page 148 Which of the following parts of a wheat kernel is especially rich in vitamins and minerals? a. endosperm b. germ c. husk d. bran germ How many grams of fiber per day does the American Dietetic Association suggest for an average adult? a. 35-45 grams per day b. 20-35 grams per day c. 10-20 grams per day d. 5-10 grams per day •Men, age 19-50: 38 g/day. •Men, age 51 and up: 30 g/day. •Women, age 19-50: 25 g/day. •Women, age 51 and up: 21 g/day. •No Tolerable Upper Intake Level for fiber has been established. Which of the following would be the most nutrient-dense choice from the grains group? a. English muffin b. doughnut c. croissant d. biscuit English Muffin Which of the following carbohydrates is NOT found in foods from plants? a. sucrose b. glycogen c. starch d. fructose glycogen.Liver and muscle ce Continue reading >>

Galactose

Galactose

For the EP by The Sweet Science, see Galactose (EP). Galactose (galacto- + -ose, "milk sugar"), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose.[1] It is a C-4 epimer of glucose.[2] Galactan is a polymeric form of galactose found in hemicellulose, and forming the core of the galactans, a class of natural polymeric carbohydrates.[3] Etymology[edit] The word "Galactose" is coined by Charles Weissman[4]in mid 19th century from Greek galaktos("milk") and the generic chemical suffix for sugars -ose.[5] Structure and isomerism[edit] Galactose exists in both open-chain and cyclic form. The open-chain form has a carbonyl at the end of the chain. Four isomers are cyclic, two of them with a pyranose (six-membered) ring, two with a furanose (five-membered) ring. Galactofuranose occurs in bacteria, fungi and protozoa ,[6] and is recognized by a putative chordate immune lectin intelectin through its exocyclic 1,2-diol. In the cyclic form there are two anomers, named alpha and beta, since the transition from the open-chain form to the cyclic form involves the creation of a new stereocenter at the site of the open-chain carbonyl. In the beta form, the alcohol group is in the equatorial position, whereas in the alpha form, the alcohol group is in the axial position.[7] Cyclic forms of galactose Relationship to lactose[edit] Galactose is a monosaccharide. When combined with glucose (monosaccharide), through a condensation reaction, the result is the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase. The latter is produced by the lac operon in Escherichia coli. In nature, lactose is found primarily in milk and milk products. Consequentl Continue reading >>

Glucose-galactose Malabsorption - Genetics Home Reference

Glucose-galactose Malabsorption - Genetics Home Reference

Glucose-galactose malabsorption is a condition in which the cells lining the cannot take in the sugars glucose and galactose, which prevents proper digestion of these molecules and larger molecules made from them. Glucose and galactose are called simple sugars, or monosaccharides. Sucrose (table sugar) and lactose (the sugar found in milk) are called disaccharides because they are made from two simple sugars, and are broken down into these simple sugars during digestion. Sucrose is broken down into glucose and another simple sugar called fructose, and lactose is broken down into glucose and galactose. As a result, lactose, sucrose and other compounds made from sugar molecules (carbohydrates) cannot be digested by individuals with Glucose-galactose malabsorption generally becomes apparent in the first few weeks of a baby's life. Affected infants experience severe diarrhea resulting in life-threatening dehydration, increased acidity of the blood and tissues (acidosis), and weight loss when fed breast milk or regular infant formulas. However, they are able to digest fructose-based formulas that do not contain glucose or galactose. Some affected children are better able to tolerate glucose and galactose as they get older. Small amounts of glucose in the urine (mild glucosuria) may occur intermittently in this disorder. Affected individuals may also develop kidney stones or more widespread deposits of calcium within the kidneys. SLC5A1 gene provides instructions for producing a sodium/glucose cotransporter protein called SGLT1. This protein is found mainly in the intestinal tract and, to a lesser extent, in the kidneys, where it is involved in transporting glucose and the structurally similar galactose across cell membranes. The sodium/glucose cotransporter protein is impor 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 >>

Bio 200 Flashcards

Bio 200 Flashcards

a. the ability of electrons to repel each other b. the strength of "pull" a nucleus has on electrons in a covalent bond c. the measure of negativity on an electron b. the strength of "pull" a nucleus has on electrons in a covalent bond In a covalent bond between carbon and oxygen... (choose all that apply) a. the oxygen will have a net partial negative charge b. electrons spend more time orbiting oxygen c. electrons are "pulled" harder by oxygen a. the oxygen will have a net partial negative charge b. electrons spend more time orbiting oxygen c. electrons are "pulled" harder by oxygen Choose all correct statements about methane (CH4) b. methane is soluble in water becuase it has tetrahedral symmetry c. The four bonds are all 90 degrees apart from each other d. methan is soluble in water beause it forms hydrogen bonds with the oxygen in water Which of the following are possible functions of carbohydrates? d. act as a structural component of cells and organisms d. act as a structural component of cells and organisms Glucose and galactose are monosaccharides (sugars) with the same number of carbons. What else is true about these two sugars? (Choose all correct answers) a. they have the same function (can be used by the cell in the same way) d. they have the same molecular structure (spatial orientation) a. starches and glycogen are both made up of glucose monomers d. starches and glycogen contain alpha-1,4 and alpha-1,6 glycosidic linkages Cellulose, the carbohydrate in plant cell walls, is not digestible by human enzymes. What is true about cellulose? (Choose ALL correct answers) a. cellulose is also made by animals and is used for energy storage b. cellulose polymers hydrogen bond with one another c. cellulose sheets are strong, making them useful structurally b. cellul Continue reading >>

Identifying Disaccharides - Biochemistry

Identifying Disaccharides - Biochemistry

Lactose is a disaccharide that needs to be broken down to its monosaccharide components in the gut (so that it can be absorbed). Lactose is made up of galactose and glucose monosaccharide units. An enzyme called lactase, found on the intestinal walls, is used to break down lactose to galactose and glucose. A person with lactose intolerance lacks lactase and, therefore, cannot break down lactose to its components. This leads to malabsorption of lactose. However, there is no problem with galactose and glucose absorption. This means that a patient with lactose intolerance can still digest galactose and glucose if given separately. As the question states, hypoglycemia is characterized by low levels of glucose in the blood. To bring the glucose levels back to normal, one can ingest foods that contain high amounts of glucose. To solve this question we need to decide which of the stated options can be broken down to glucose. Lactose is a disaccharide that is made up of glucose and galactose. An enzyme, called lactase, breaks down lactose to its components, which can then be absorbed by the intestinal cells; therefore, ingesting glucose will increase glucose levels in the blood. Similarly, sucrose is a disaccharide made up of fructose and glucose; therefore, ingesting sucrose will also increase glucose levels in the blood. Galactose is a monosaccharide and, therefore, cannot be broken down to any further. It is absorbed as galactose by the intestinal cells. This will not increase the concentration of glucose in the blood. If you believe that content available by means of the Website (as defined in our Terms of Service) infringes one or more of your copyrights, please notify us by providing a written notice (Infringement Notice) containing the information described below to the Continue reading >>

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