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51 Cards in this Set
- Front
- Back
In people with diabetes,glucose is not removed from the blood and hence cannot bestored in reserve. This leads to a lack of the synthesis of___________________.
A.cellulose B. glycogen C. ATP D. starch. E. sucrose |
B.Glycogen
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Which of the following terms includes all others?
B. disaccharide C. starch D. polysaccharide E. carbohydrate |
E. Carbohydrate
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Which of the following molecules would NOT be found in plants?
A. starch B. glucose C. cellulose D. glycogen E. phospholipids |
D. Glycogen
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When a carbonyl is found at the end of a monosaccharide, _(4)_.
A. the sugar is called an aldose B. the sugar is called a carbonose C. the sugar is called a ketose D. Trick question –monosaccharides do not have carbonyl groups! |
A. this sugar is an ALDOSE
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What is the major structural difference between glycogen and starch?
B. The degree of branching. C. The length of the molecule D. There is no difference |
B. The degree of branching
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What polysaccharide is an important component inthe structure of many insects and fungi?
A. Cellulose. B. Starch. C. Chitin. D. Protein. E. Glycogen. |
C. Chitin
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Enzymes that readily break apart starch cannothydrolyze the bonds found in cellulose. Why is this logical?
A. The geometry of the moleculesare different, and enzymes are shape-specific. B. Starch is held together by hydrogen bonding,not covalent bonding. C. Cellulose molecules are highly branched; enzymes are too bulky to fit. D. Cellulose molecules are not put together bydehydration synthesis, and thus could not be broken by hydrolysis? |
A. The geometry is different, and enzymes are shape-specific
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List some of the functions of carbohydrates
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Carbohydrates have six major functions within the body:
1. Providing energy and regulation of blood glucose 2. Sparing the use of proteins for energy 3. Breakdown of fatty acids and preventing ketosis 4. Biological recognition processes 5. Flavor and Sweeteners 6. Dietary fiber |
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The alpha and beta forms of glucose, found in starch and cellulose, differ in ...
(a) Whether the molecule is a ring or an open chain. (b) Whether the ring contains five or six C atoms. (c) Whether the first C atom is bound to one or two O atoms. (d) How one of the -OH groups is oriented. (e) None of the above. |
(d) How one of the -OH groups is oriented.
One particular -OH group points to one side of the ring in alpha glucose; the other side in beta glucose. |
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Which feature is shared by all monosaccharides?
(a) In their linear forms, they all contain a carbonyl and several hydroxyl functional groups. (b) They are all pentoses. (c) In their linear forms, they all contain a carboxyl and several hydroxyl functional groups. (d) They all contain more than one sugar. |
(a) In their linear forms, they all contain a
carbonyl and several hydroxyl functional groups. |
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How do the α and β forms of glucose differ?
(a) Their ring structures differ in the location of a hydroxyl group. (b) Their linear structures differ in the location of a hydroxyl group. (c) The α form can be involved in 1,4- and 1,6-glycosidic linkages; the β form can participate only in 1,4 linkages. (d) The oxygen atom inside the ring is located in a different position. |
(a) Their ring structures differ in the location of a hydroxyl group. |
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Glycogen is _____.
(a) A source of saturated fat (b) A polysaccharide found in animals (c) A transport protein that carries oxygen (d) A polysaccharide found in plant cell walls (e) The form in which plants store sugars |
(b) A polysaccharide found in animals
Animals store energy in the form of glycogen. |
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_____ is the most abundant organic compound on Earth.
(a) Cellulose (b) Glucose (c) Starch (d) Glycogen (e) Lactose |
(a) Cellulose
Cellulose, a component of plant cell walls, is the most abundant organic compound found on earth. |
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Which statement is true of sucrose?
(a) It's a disaccharide. (b) It contains glucose. (c) It's table sugar. (d) Both (a) and (c). (e) - (a), (b), and (c). |
(e) - (a), (b), and (c)
We use sucrose as our table sugar because plants make plenty of it. They use it as their main circulating fuel, and sugar beets and sugar cane store a lot of it. It's a disaccharide made of glucose and fructose . |
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Glycogen ...
(a) Contains several kinds of sugars. (b) Occurs in animal cells and has branches. (c) Is stronger, weight for weight, than steel. (d) Occurs in chloroplasts and stores energy. (e) None of the above. |
(b) Occurs in animal cells and has branches.
Glycogen is the main energy-storing carbohydrate in animals and humans. |
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Which of the following structural features is
common to cellulose, chitin, and peptidoglycan? (a) They can all form bonds between polymer chains that create parallel strands. (b) They are all composed of glucose in either the α or β form. (c) They are all composed of highly branched fibers. (d) They all contain peptide bonds. |
(a) They can all form bonds between polymer chains that create parallel strands.
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Cellulose is _____.
(a) A monomer of starch. (b) A major structural component of plant cell walls (c) A polymer composed of fructose monomers (d) Used by plants to make glycogen (e) A storage polysaccharide for energy in plant cells |
(b) A major structural component of plant cell walls .
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What is "high fructose corn syrup" ? |
High-fructose corn syrup is a common sweetener in sodas and fruit-flavored drinks
made from corn starch. |
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Define and explain the realtionship between Monosaccharides, triose, pentose and hexose? |
Monosaccharides: most taste sweet; contain 3-7 carbon atoms, are either: ALDOSE (conatin an aldehyde group, or KETOSE (contain a ketose group); their names are composed by denoting the number of carbon atoms and the suffix -ose. For example, the terms triose, pentose, and hexose signify monosaccharides with, respectively, three, five, and six carbon atoms. |
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Define: Aldose, Ketose and isomers |
Monosaccharides are the simplest form of carbohydrates and may be subcategorized as aldoses or ketoses. The sugar is an aldose if it contains an aldehyde functional group Isomeres are any of two or more substances that have the same molecular formula but differ in the way their atoms are connected to each other. Glucose, fructose and galactose are isomers, they have the same chemical formula (C6H12O6), but different structures. |
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What are Oligosaccharides and Polysaccharides? |
Oligosaccharides are carbohydrates formed by the joining of 2 to 6 monosaccharide molecules,ie. Maltose - disaccharide formed in cells as a breakdown product of starch; Lactose - is a disaccharide found in milk and hence commonly called milk sugar; Sucrose is disaccharide found
extensively in plants. It is commonly called cane sugar.Polysaccharides: made up of many simple sugars chemically joined together (poly= many), ie.Starch (energy store in plants), glycogen (energy store in animals), Cellulose (plant fibre) |
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What are Monosaccharides? |
"Simple sugars" with the formula (C • H2O)n.
A monosaccharide is made up of one sugar (mono=one). Have endings with "ose" : Fructose ("Fruit Sugar"), Glucose, Galactose |
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What are Carbohydrates? |
Carbohydrates are also known as sugars.
They are compounds of carbon, hydrogen and oxygen: C,H,O 1C : 2O : 1O (ie. C6H12O6) Functions: * serve as raw material for synthesizing other molecules * provide fibrous structural materials * indicate cell identity * store chemical energy |
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What are disaccharides? |
A disaccharide is made up of two simple sugars chemically joined
together (di=2). Examples: Sucrose (Glucose + fructose = sugar cane/sugar beets) Lactose (galactose + glucose = milk) Maltose (glucose + glucose = in germinating grain) |
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What are Glycoproteins ?
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Glycoproteins are proteins that have sugars attached to them. They have diverse functions such as in our immune system, protection of our body, communication between cells, and our reproductive systems. |
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What are monomers? |
Monomers=monosaccharides They are monosaccharides that polymerize via condensation reactions to form polymers like polysaccharides. The monosaccharides in polysaccharides are joined by glycosidic linkages. |
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What are the functional groups of monomers, or monosaccharides? |
Carbonyl C=O + Hydroxyl OH- |
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What are polymers? |
Oligosaccahrides: small polymers (oligo=few) (3-50 monosaccharides) Polysaccharieds: many polymers (poly=many) (over 50 monos) |
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Monosaccharides vary in structure by: |
1. Location of the carbonyl group= they have one carbonyl - at either end of the sugar, or in the middle of the sugar thus called Aldose, or Ketose 2. Number of Carbon atoms (Triose=3; Pentose=5; Hexose=6) 3. Spatial arrangement of the atoms (configuration/location of the hydroxyl (C-OH) groups) 4. Linear and alternative ring forms (Sugars tend to form rings in aqueous solutions) |
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Difference between Aldose and Ketose? |
left: carbonyl (C=O) group at the end of the carbon (C) chain=ALDOSE right: carbonyl group in the middle of the carbon chain= KETOSE
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Draw chemical formula of an aldose and a ketose |
Glucose: 6 carbon aldehyde sugar Fructose: 6 carbon ketose sugar |
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Sugars exist in linear and ring forms |
Sugars normally have 3-7carbons and form ring shapes, if they have 5 carbons or more example here: GLUCOSE (in linear and ring form) |
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draw the glycosidic linkage of the disaccharide Maltose |
Maltose: The hydroxyl group on C-1 is bonded with the hydroxyl group of C-4 of another molecule in form of a glycosidic link with the elimination of water (h2O) |
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re the 2 most comm |
2 most common glycosidic linkages: α(1→4) glycosidic bonds and β(1→4) glycosidic bonds Linkage of sugars by hydrolysis takes place on the C1 carbon OH group of the first ring in the α position and the C4 carbon OH group on the second ring. This connection is called a α(1→4) glycosidic bond,i.e.maltose, glycogen. Linkage of the β glucose molecules on C1 and C4 OH group is called β(1→4) glycosidic bonds, ie. cellulose. |
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what is α and β Glucose? |
in β Glucose the OH group on C1 is pointing up in α Glucose the OH group on C1 is pointing down |
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2 most common glycosidic linkages:α(1→4) glycosidic bonds and β(1→4) glycosidic bonds |
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What are macromolecules? |
Have fifty-ish to thousands ofmonosaccharide monomers linked bydehydration synthesis = macromolecules! 1. Starch 2. Glycogen 3. Cellulose 4. Chitin 5. Peptidoglycan |
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what are examples of polysaccharides? |
1. Glycogen in animals (highly branched α-glucose polymer) 2. Starch in plants (mixture of branched andunbranched α-glucose polymer) 3. Cellulose in plants (polymer of β-glucose monomers) 4. Chitin in fungi/algae (comprised of N-acetylglucosamine (NAc) monomers) 5. Peptidoglycan in bacterial cell walls (backbones of alternating monosaccharides) |
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What is starch? |
Storage (fuel) polysaccharide in plants the glucose molecules form helices in form of amylose (unbranched), or amylopectin (branched) |
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What is glycogen? |
* Storage (fuel) polysaccharide in animals * All of glucose * Molecules form helices * HIGHLY branched (more so than amylopectin) |
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what is cellulose? |
Structural polysaccharide (cell wall support) in plants All of β-glucose with β(1→4) linkage Molecules form rods, sheets Unbranched Most abundant molecule on Earth! |
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what is chitin? |
Structural polysaccharide – Cell walls of fungi •Chitin is a modified polysaccharide that contains nitrogen (all of one N-containing glucose derivative) •Exoskeletons of arthropods •Molecules form rods, sheets •Unbranched |
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what is peptidoglycan ? |
Structural (cell wall) polysaccharide in bacteria •All of N-containing glucose derivatives covalently cross-linked with short proteins (peptido=Protein; Glycan=glucose derivative) • Molecules form rods, sheets • “Un”branched (polysaccharide component) |
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How Do Carbohydrates Provide Structure? |
* Cellulose, chitin, and peptidoglycan form long strands then organized into fibres, orlayered in sheets, to give cells and organisms greatstrength and elasticity! * the β-1,4-glycosidic linkages ofstructural carbohydrates are very difficult to hydrolyze |
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What do Carbohydrates Do? |
A. Furnish building blocks: used directly (in RNA), or can provide raw “carbon skeletons” (in amino acids) B. Provide: their shape makes them difficult to break (Chitin; Cellulose) C. Cell Identity: as Glycoproteins (proteins joined to carbohydrates bycovalent bonds) - cell-cell recognition andcell-cell signalling ie. red blood cells - different blood types D. Store/provide chemical energy in cells (photosynthesis in plants/ATP)
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Explain Photosynthesis equation |
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Energy Stored in Glucose Is Transferred to ATP |
When a cell needs energy, carbohydrates participate inexergonic reactions that synthesize adenosine triphosphate(ATP): CH2O + O2 + ADP + Pi → CO2 + H2O + ATP Carbohydrates contain a large number of C–H bonds, whichhave high free energy. |
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How Do Carbohydrates Store Energy? |
Starch and glycogen are efficient energy-storagemolecules, because the α-linkages are readilyhydrolyzed, The enzymes amylase and phosphorylase catalyzethe hydrolysis of α-glycosidic linkages inglycogen and starch, respectively. The releasedglucose subunits can then be used in theproduction of ATP. |
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Taste receptors and sweeteners |
* We have taste receptors (TAS1R3) for sweetness, this tells us a food is high in energy. * A common sweetener, glucose–fructose (also called highfructose corn syrup) is found in processed foods * made by converting starch to glucose, then some glucose is converted tofructose because glucose-fructose is both sweeter and cheaper than sucrose |
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Artificial sweeteners |
* Sucrose, sucralose, saccharin... * Artificial sweeteners taste sweet becausethey bind to the TAS1R3 (taste) receptor in tongue. * The hydroxyl groups (OH) on sucrosereplaced with chlorine (Cl) |
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Types of Sweeteners Made from Plant Sugars? |
1. Table sugar (sucrose): from sugar beets/cane 2. Honey (glucose/fructose mixture): flower nectar + bees 3. Glucose-Fructose: Corn + corn starch |