Chapter 23 Terms: Carbohydrates And Nucleic Acids

Front 1

aglycone

Back 1

a non-sugar bonded to the anomeric carbon of a glycoside.
Commonly bonded to the sugar through nitrogen or oxygen.

Hint 1

the acetal form of a sugar

Front 2

aldaric acid

Back 2

a dicarboxylic acid formed by the oxidation of both end carbon atoms of monosaccharide

Hint 2

also known as a glycaric or saccharic acid

Front 3

alditol

Back 3

a polyalcohol formed by reduction of the carbonyl group of a monosaccharide

Hint 3

also known as sugar alcohol

Front 4

aldose

Back 4

a monosaccharide containing an aldehyde group

Front 5

anomeric carbon

Back 5

the hemiacetal carbon in the cyclic form of a sugar. Easily identifiable because it is the only carbon with two bonds to oxygen atoms

Front 6

anomers

Back 6

sugar steroisomers that differ in configuration only at the anomeric carbon. Classified as α or β depending on whether the anomeric hdroxyl group is trans (α) or cis (β) to the terminal -CH2OH

Front 7

carbohydrates

Back 7

polyhydroxy aldehydes and ketones, including their derivatives and polymers.

Hint 7

Many of these have the formula (Cn(H2O))m found from which they receive their name.

Front 8

Cellulose

Back 8

a linear β-1,4' polymer of D-glucopyranose.

Hint 8

It forms on the cell walls of plants and is a major constituent of wood and cotton.

Front 9

Chitin

Back 9

A β-1,4' polymer of N-acetylglucoseamine that lends strength and regidity to the exoskeleton of insects and crustacians

Hint 9

the beetle's shiny shell is made of this

Front 10

Degradation

Back 10

a reaction that causes a loss of a carbon atom

Front 11

deoxyribonucleic acid (DNA)

Back 11

a biopolymer of deoxyribonucleotides that serves as a template for the synthesis of ribonucleic acid. It is also the template for its own replication.

Front 12

deoxy sugar

Back 12

a sugar in which a hydroxyl group is replaced by a hydrogen. These are recognized by the presence of a methylene group or a methyl group

Front 13

dextrose

Back 13

the common dextrorotatory isomer of glucose.

Front 14

D series of sugars

Back 14

all sugars whose asymmetric carbon atom farthest away from the carbonyl group has the same configuration as the asymmetric carbon in D-(+)-glyceraldehyde. Most naturally occurring sugars are of this group

Front 15

disaccharide

Back 15

a carbohydrate whose hydrolysis gives two monosaccharide molecules

Front 16

enediol rearrangement

Back 16

a base-catalyzed tautomerization that interconverts aldoses and ketoses with an enediol as an intermediate. This enolization also epimerizes C2 and other carbon atoms.

Front 17

epimers

Back 17

two diastereomic sugars differing only in the configuration of a single asymmetric carbon atom.

Front 18

erythro and threo

Back 18

diastereomers having similar groups on the same side (erythro) or on opposite sides (threo) of the Fischer projection.

Front 19

furanose

Back 19

a five-membered cyclic hemiacital form of sugar

Front 20

furanoside

Back 20

a five-membered cyclic glycoside

Front 21

glucoside

Back 21

a glycoside derived from glucose

Front 22

glycoside

Back 22

a cyclic acetal form of a sugar.

These are stable as a base, and are nonreducing sugars.

Front 23

glycosidic linkage

Back 23

a general term for an acetal bond from an anomeric carbon joining two monosaccharide units

Front 24

glucosidic linkage

Back 24

a glycosidic linkage using an acetal bond from the anomeric carbon of glucose

Front 25

galactosidic linkage

Back 25

a glycosidic linkage using an acetal bond from the anomeric carbon of galactose

Front 26

Haworth projection

Back 26

a flat-ring representation of a cyclic sugar.

Front 27

Ketose

Back 27

a monosaccharide containing a ketone carbonyl group

Front 28

Kiliani-Fischer synthesis

Back 28

a method for elongating an aldose at the aldehyde end.

The aldose is converted into two epimeric aldoses with an additional carbon atom.

Front 29

L series of sugars

Back 29

all sugars whose asymmetric carbon atom farthest from the carbonyl group has the same configuration as the asymmetric carbon atom farthest from the carbonyl group has the same confiuration as the asymmetric carbon atom in L-(-)-glyceraldehyde.

Not common in nature

Front 30

mutarotation

Back 30

a spontaneous change in orbital rotation that occurs when a pure anomer of a sugar in its hemiacetal form equilibrates with the other anomer to give an equilibrium mixture with an averaged value of the optical rotation

Front 31

nucleoside

Back 31

an N-glycoside of β-D-ribofuranose or β-D-deoxyribofuranose, where the aglycone is one of several derivatives of pyrimidine or purine

Front 32

nucleotide

Back 32

a 5'-phosphate ester of a nucleoside

Front 33

osazone

Back 33

the product, containing two phenylhydrazone groups, that results from reaction of a reducing sugar with phenylhdyrazine.

Front 34

pyranose

Back 34

a six-membered cyclic hemiacetal form of a sugar

Front 35

pyranoside

Back 35

a six-membered cyclic glycoside

Front 36

reducing sugar

Back 36

any sugar that gives a positive Tollen's test.

Front 37

Ribonucleic acid (RNA)

Back 37

A biopolymer of ribonucleotides that conrols the synthesis of proteins. The synthesis of RNA is generally controlled by and patterned after DNA in the cell.

Front 38

ribonucleotide

Back 38

The 5'-phosphate ester of a ribonucleoside, a component of RNA baed on β-D-ribofuranose and containing one of four heterocyclic bases.

Front 39

Ruff degradation

Back 39

a method for shortening the chain of an aldose by one carbon atom by treatment with bromine water, followed by hydroen peroxide adn Fe2(SO4)3.

Front 40

starches

Back 40

a class of α-1,4' polymer of D-glucopyranose used for carbohydrate storage in plants and animals

Front 41

sugar

Back 41

any carbohydrate, reguardless of structure, complexity or taste.

Front 42

Tollens test

Back 42

a test for reducing sugars, employing the same silver-ammonia complex used as a test for aldehydes. A positive gives a silver precipitate.