Term
| _________ are aldehyde or ketone derivatives of straight-chain polyhydroxy alcohols containing at least three carbon atoms |
|
Definition
|
|
Term
| They are classified according to the chemical nature of their carbonyl group and the number of their C atoms? |
|
Definition
|
|
Term
| If the carbonyl group is an aldehyde, the sugar is an ___________ |
|
Definition
|
|
Term
| If the carbonyl group is a ketone, the sugar is a _____________ |
|
Definition
|
|
Term
| The smallest monosaccharides, those with three carbon atoms, are ___________ |
|
Definition
|
|
Term
Those with four, five, six, seven, etc. C atoms are, respectively,
________, ______________, _______________, ________________, etc. |
|
Definition
| tetrose, pentose, hexose, heptoses, etc. |
|
|
Term
| The aldohexose D-glucose has the formula _________ |
|
Definition
|
|
Term
All but two of its six C atoms, C1 and C6, are chiral centers, so D-glu- cose is one of 24 16 possible stereoisomers.
True
False |
|
Definition
|
|
Term
Are the L sugars mirror images of the D sugars?
Yes
NO |
|
Definition
|
|
Term
| Sugars that differ only by the configuration around one C atom are known as ___________ of one another. |
|
Definition
|
|
Term
Are D-glucose and D-manose epimers with respect to C2?
Yes
No |
|
Definition
| Yes. google an image of these two sugars and compare... |
|
|
Term
| The most common aldoses include the six-carbon sugars _________, ______________, __________________. |
|
Definition
| glucose, monnose, and galactose. |
|
|
Term
| The pentose _____________ is a component of the ribonucleotide residues of RNA. |
|
Definition
|
|
Term
| The triode _________________ occurs in several metabolic pathways. |
|
Definition
|
|
Term
The most common ketone are those with their ketone function at C3.
True
False |
|
Definition
False.
The most common ketoses are hose with their ketone function at C2 |
|
|
Term
The position of their carbonyl group gives ketoses one more asymmetric center than their isomeric aldoses.
True
False |
|
Definition
False.
The position of their carbonyl group gives ketoses one less asymmetric center than their isomeric aldoses, so a ketohesose has only 2^3 = 8 possible stereoisomers (4 D
sugars and 4 L sugars). |
|
|
Term
| The most common ketoses are __________________, ________________, and _____________________. |
|
Definition
| dihydroxyacetone, ribulose, and fructose. |
|
|
Term
Do monosaccharides vary in configuration and transformation?
yes
no |
|
Definition
no.
monosaccharides vary in configuration and conformation |
|
|
Term
| Alcohols react with the carbonyl groups of aldehydes and ketones to form __________________ and ____________________. |
|
Definition
| hemiacetals and hemiketals. |
|
|
Term
| The biologically most common aldoses are _________________, ____________________, and _____________________. |
|
Definition
| D-Ribose (Rib), D-Glucose (Glc), and D-Mannose (Man). |
|
|
Term
| The biologically most common ketoses are ______________, and ___________________. |
|
Definition
| D-Ribulose and D-Fructose. |
|
|
Term
| What is the number of L-ketoses? |
|
Definition
|
|
Term
The hydroxyl and either the aldehyde or the ketone functions of monosaccharides can likewise react intramolecularly to form cyclic hemiacetals and hemiketals.
True
False |
|
Definition
|
|
Term
The linear form of D-glucose yields the cyclic hemiacetal beta -D-fructofuranose.
True
False |
|
Definition
False.
D-glucose yields the cyclic hemieacetal beta -D- glucopyranose. |
|
|
Term
The linear form of D-fructose yields the hemiketal beta -D-fructofuranose.
True
False |
|
Definition
|
|
Term
| A sugar with a six-member ring is known as a ______________. |
|
Definition
|
|
Term
| Sugars with five-membered rings are known as _________________. |
|
Definition
|
|
Term
| The cyclic forms of glucose and fructose with six- and five- membered rings are therefore known as ________________ and __________________. |
|
Definition
| glucopyranose and fructofuranose |
|
|
Term
Cyclic sugars have three anomeric forms.
True
False |
|
Definition
False
Cyclic sugars have TWO anomeric forms. |
|
|
Term
| When a monosaccharide cyclizes, the carbonyl carbon, called the ___________ _________, becomes a chiral center with two possible configurations. |
|
Definition
|
|
Term
| The pair of stereoisomers the differ in configuration at the anomeric carbon are called ____________. |
|
Definition
anomers.
If you remember all of this you'll get an A.
keep going!
do at least 10 cycles. |
|
|
Term
can a hexose or pentose assume pyranose or furganose forms?
yes
no |
|
Definition
|
|
Term
| The _______ __________ of three- and four-membered rings makes them less stable than the linear forms. |
|
Definition
|
|
Term
| The pyranose ring, like the cyclohexane ring, can assume a ________ conformation, in which the substituents of each atom are arranged tetrahedrally. |
|
Definition
|
|
Term
| Of the two possible chair conformations, the one that predominates is the one in which the bulkiest ring substituents occupy ______________ positions rather than the more crowded _____________ positions. |
|
Definition
|
|
Term
| Only ____________________ can simultaneously have all five of its non-H substituents in equatorial positions. |
|
Definition
|
|
Term
| monosaccharides can readily shift is ____________________, because no bonds are broken in the process. |
|
Definition
|
|
Term
| Other changes in conformation, such as __________________, do not occur under physiological conditions without the appropriate enzyme. |
|
Definition
|
|
Term
Can sugars be modified and covalently linked?
no
yes |
|
Definition
|
|
Term
| Because the cyclic and linear forms of aldose and ketoses do ______________, these sugars undergo reactions typical of aldehydes and ketones. |
|
Definition
|
|
Term
| Oxidation of an aldose converts its aldehyde group to a carboxylic acid group, thereby yielding an ___________ _______ such as ____________ _______. |
|
Definition
| aldonic acid gluconic acid |
|
|
Term
| Oxidation of the primary alcohol group of aldoses yields _________ _______. |
|
Definition
|
|
Term
| Uronic acids can assume the _____________, ______________, and ___________ forms. |
|
Definition
| pyranose, furganose, linear |
|
|
Term
Aldose and ketoses can be reduced under heavy conditions?
true
false |
|
Definition
false.
aldose and ketoses can be reduced under mild conditions. |
|
|
Term
| Treatment with NaBH4 yields polyhydroxy alcohols known as ____________. |
|
Definition
|
|
Term
| _____________is a component of flavin coenzymes, and _______________ and the cyclic polyhydroxy alcohol ___________ are important lipid components. |
|
Definition
| Ribitol glycerol myoinositol |
|
|
Term
| _______________ is a sweetener that is used in "sugarless" gum and candies. |
|
Definition
|
|
Term
| Monosaccharide units in which an OH group is replaced by H are known as ________ _____________. |
|
Definition
|
|
Term
| The biologically dos important of these is _______________________, the sugar component of DNA's sugar-phosphate backbone. |
|
Definition
|
|
Term
| _____________ is one of the few L sugar components of polysaccharides. |
|
Definition
|
|
Term
| In _______________ _________, one or more OH groups have been replaced by an amino group, which is often acetylated. |
|
Definition
|
|
Term
| The two most common amino sugars are ___________________, _____________________. |
|
Definition
| D-Glucosamine D-galactosamine |
|
|
Term
| ________________ ________, which is derived rom N-acetylmannosamine and pyruvic acid. |
|
Definition
|
|
Term
| N-Acetylneuraminic acid is an important constituent of ______________ and _______________. |
|
Definition
| glycoproteins and glycolipids |
|
|
Term
| N-acetyleruaminic acid and its derivatives are often referred to as ____________ _______. |
|
Definition
|
|
Term
In the cyclic form of N-Acetylneraminic acid, the pyranose ring incorporates the pyruvic acid residue and part of the mannose moiety.
Yes
NO |
|
Definition
|
|
Term
| ______________ bonds link the Anomeric Carbon to other compounds. |
|
Definition
|
|
Term
| The anomeric group of a sugar can _________________ with an alcohol to form alpha and beta glycosides. |
|
Definition
|
|
Term
| The bond connecting the anomeric carbon to the alcohol oxygen is termed a __________________ __________. |
|
Definition
|
|
Term
| N-Glycosidic bonds, which form between the ____________ carbon and an _____________, are the bonds that link D-ribose to purines and pyrimidines in nucleic acids. |
|
Definition
|
|
Term
Like peptide bonds, glycosidic bonds hydrolyze extremely fast under physiological conditions in the absence of appropriate hydrolytic enzymes.
True
False |
|
Definition
False.
In the absence of appropriate hydrolytic enzymes, glycosidic bonds hydrolyze extremely slow. |
|
|
Term
Can a anomeric carbon that is involved in a glycosidic bond freely convert between its alpha and beta anomeric forms?
Yes
NO |
|
Definition
No.
An anomeric carbon that is involved in a glycosidic bond cannot freely convert between its alpha and beta anomeric forms. |
|
|
Term
| Saccharides bearing anomeric carbons that have not formed glycosides are termed ________________ __________. |
|
Definition
|
|
Term
Saccharides bearing anomiric carbons that have not formed glycosides are termed reducing sugars, because the free aldehyde group that is in equilibrium with the cyclic form of the sugar reduces mild oxidizing agents.
True
False |
|
Definition
|
|
Term
| Identification of a sugar as nonreducing is evidence that it is a _________________. |
|
Definition
|
|
Term
| Disaccharides such as _____________ and ____________ consist of two sugars linked by specific glycosidic bonds. |
|
Definition
|
|
Term
| ___________ and ______ are polymers of beta(1-->4)-linked glucose residues. |
|
Definition
|
|
Term
| In __________ and ____________, glucose residues are linked mainly by alpha(1-->4) bonds. |
|
Definition
|
|
Term
| ___________________ and other large _____________________ typically have a gel-like structure. |
|
Definition
| Glycosaminoglycans heteropolysaccharides |
|
|
Term
| Polysaccharides, which are also known as ____________, consist of _________________ linked tighter by __________ bonds. |
|
Definition
| glycans monosaccharides glycosidic |
|
|
Term
| Polysaccharides are classified as _____________________ or ________________________ if they consist of one type or more than one type of monosaccharide. |
|
Definition
| homopolysaccharides heteropolysaccharides |
|
|
Term
| Polysaccharides, in contrast to proteins and nucleic acids, form __________ as well as __________ polymers. |
|
Definition
|
|
Term
| Polysaccharides, in contrast to proteins and nucleic acids, form branched, as well as linear polymers, because ______________ linkages can be made to any of the _______________ groups of a monosaccharide. |
|
Definition
|
|
Term
| A complete description of an _________________ or polysaccharide includes the ____________, ______________ forms, and ____________ of all its component monosaccharide units. |
|
Definition
| oligosaccharide identities anomeric linkages |
|
|
Term
| Information about oligosaccharides or polysaccharides can be gathered through the use specific _______________________ and ______________________, enzymes that hydrolyze monosaccharides units in much the same way that exopeptidases and endopeptidase cleave amino acid residues from polypeptides. |
|
Definition
| exoglycosidases endoglycosidases |
|
|
Term
| ________ measurements are also invaluable in determining both sequences and conformations of polysaccharides. |
|
Definition
|
|
Term
Lactose and Sucrose are monosaccharides.
True
False |
|
Definition
False.
Lactose and Sucrose are Disaccharides |
|
|
Term
Oligosaccharides containing three or more residues are relatively rare, occurring almost in plants.
True
False |
|
Definition
|
|
Term
| ___________________, the simplest polysaccharides, are more common. |
|
Definition
|
|
Term
Many disaccharides occur as the hydrolysis products of small molecules.
true
false |
|
Definition
false.
Many disaccharides occur as the hydrolysis products of large molecules. |
|
|
Term
| __________ occurs, naturally only in milk, where its concentration ranges from 0 to 7% depending on the species. |
|
Definition
|
|
Term
| The systematic name for lactose, ____________________________________________________, specifies its monosaccharides, their ring types, and how they are linked together. |
|
Definition
| O-beta-D-galactopyranosyl-(1-->4)-D-glucopyranose |
|
|
Term
The symbol (1-->4) from O-beta-D-galactopyranosyl-(1-->4)-D-glucopyranose indicates that the glycosidic bond links C2 of the beta anomer of galactose to O4 of glucose.
True
False |
|
Definition
False.
glycosidic bonds links C1 of the beta anomer of galactose to O4 of glucose. |
|
|
Term
Lactose has a free anomeric carbon on its glucose residue and is therefore a reducing sugar.
True
False |
|
Definition
|
|
Term
| The most abundant disaccharide is _______________, the major form in which _____________________ are transported in __________. |
|
Definition
| sucrose carbohydrates plants |
|
|
Term
Sucrose is familiar to us as common table salt?
yes
no |
|
Definition
|
|
Term
| They systematic name for sucrose is _____________________________________. |
|
Definition
| O-alpha-D-glucopyranosyl-(1-->2)-beat-D-fructofuranoside |
|
|
Term
| The systematic name for sucrose, O-alpha-D-glucopyranosyl-(1-->2)-beta-D-fructofuranoside, indicates that the _______________ carbon of each ___________ (C1 in glucose and C2 in fructose) participates in the ________________ bonds. |
|
Definition
| anomeric sugar glycosidic |
|
|
Term
| The systematic name for sucrose, O-alpha-D-glucopyranosyl-(1-->2)-beta-D-fructofuranoside, indicates that eat anomeric carbon of each sugar (_____ in glucose and _____ in fructose) participates in the glycoside bonds. |
|
Definition
|
|
Term
| ________________ and ________ are structural polysaccharides. |
|
Definition
|
|
Term
| ______________, the primary structural component of plant cell walls, accounts for over half of the carbon in the biosphere. |
|
Definition
|
|
Term
| Cellulose is a __________ polymer of up to 15,000 __________ residues linked by ___________ glycosidic bonds. |
|
Definition
| linear D-glucose beta(1-->4) |
|
|
Term
| _________ and other studies of cellulose fibers reveal that cellulose chains are ________ ribbons in which successive glucose rings are turned over _______ with respect to each other. |
|
Definition
|
|
