chapter 7 pt 1

Question 1

what is energy?

Answer 1

fuel for most organisms

Question 2

-colorless, crystalline solids that are freely soluble in water due to many OH groups but insoluble in nonpolar solvents
-multiple asymmetric (chiral) carbons
-2^n stereoisomers
-general formula (CH2O)n

Answer 2

Monosaccharides

Question 3

monosaccharides with two or more hydroxyl groups

Answer 3

aldehydes or ketones

Question 4

two families of monosaccharides

Answer 4

aldoses & ketoses (usually at C2)

Question 5

backbones of common monosaccharides

Answer 5

unbranched carbon chains where all the carbon atoms are linked by single bonds

Question 6

describe open chain form of monosaccharides

Answer 6

one of the carbon atoms is double-bonded to an oxygen atom to form a carbonyl group; other carbon atoms have a hydroxyl group

Question 7

when the carbonyl group is at an end of the carbon chain

Answer 7

the monosaccharide is an aldose

Question 8

when the carbonyl group is at any other position (not the end)

Answer 8

the monosaccharide is a ketose

Question 9

what are the simplest monosaccharides?

Answer 9

2 three-carbon trioses:
glyceraldehyde, an aldotriose, & dihydroxyacetone, a ketotriose

Question 10

biological length of monosaccharides

Answer 10

3 to 9 carbons (5 & 6 most common) and unbranched

Question 11

what does n equal in 2^n stereoisomers?

Answer 11

n = # of chiral carbons

Question 12

monosaccharides with 4, 5, 6, & 7 carbon atoms in backbones are called

Answer 12

tetroses, pentoses, hexoses, and heptoses

Question 13

hexoses of monosaccharides

Answer 13

aldohexose D-glucose, ketohexose D-fructose

Question 14

components of nucleotides and nucleic acids

Answer 14

aldopentoses of D-ribose, 2 deoxy-D-ribose

Question 15

what type of centers do monosaccharides have?

Answer 15

-asymmetric centers
-they contain one or more asymmetric (chiral) carbon atoms and occur in optically active isomeric forms

Question 16

simplest aldose that contains one chiral center (middle carbon atom) and two different optical isomers

Answer 16

glyceraldehyde

Question 17

two different optical isomers; mirror images of each other

Answer 17

enantiomers

Question 18

when the hydroxyl group on the reference carbon is on the right (with the carbonyl carbon at the top) then the sugar is a ?

Answer 18

-D isomer
-Most organisms have D isomers

Question 19

Answer 19

L-glyceraldehyde

Question 20

Answer 20

D-glyceraldehyde

Question 21

monosaccharide that has achiral carbon

Answer 21

dihydroxyacetone

Question 22

differ in 1 or more chiral centers

Answer 22

diastereomers

Question 23

differ at only 1 carbon

Answer 23

epimers

Question 24

what are glycoconjugates?

Answer 24

complex carbohydrate polymers covalently attached to proteins or lipids that act as signals that determine the intracellular destination or metabolic fate of these hybrid molecules

Question 25

What is a carbohydrate?

Answer 25

polyhydroxy aldehydes or ketones or substances that yield such compounds on hydrolysis

Question 26

3 major classes of carbohydrates

Answer 26

-monosaccharides -oligosaccharides -polysaccharides

Question 27

-consists of short chains of monosaccharide units or residues joined by characteristic linkages called glycosidic bonds -most common form is dissacharides - with two monosaccharide units

Answer 27

Oligosaccharides

Question 28

what suffix do common monosaccharides and disaccharides have?

Answer 28

common names ending with the suffix "-ose"

Question 29

sugar polymers containing more than 20 or so monosaccharides

Answer 29

Polysaccharides

Question 30

when the hydroxyl group is on the left then its an ?

Answer 30

L isomer

Question 31

Fischer projection of ?

Answer 31

D-glucose

Question 32

How are carbons numbered?

Answer 32

carbons of a sugar are numbered beginning at the end of the atom nearest the carbonyl group

Question 33

what types of structures do common monosaccharides have?

Answer 33

cyclic structures

Question 34

ring structure formation of monosaccharides usually form derivatives called

Answer 34

hemiacetals or hemiketals

Question 35

what are hemiketals?

Answer 35

addition to a ketose

Question 36

what are hemiacetals?

Answer 36

addition to an aldose

Question 37

what bond is formed in a hemiacetal or hemiketal?

Answer 37

glycosidic linkage

Question 38

what acetal or ketal is formed when the two molecules that react are monosaccharides?

Answer 38

disaccharide

Question 39

isomeric forms of monosaccharides that differ only in their configuration about the hemiacetal or hemiketal carbon atom are called

Answer 39

anomers (carbonyl carbon atom is called anomeric carbon)

Question 40

six membered ring compounds

Answer 40

pyranoses

Question 41

stereoisomeric configurations (used for Haworth projection)

Answer 41

alpha, beta

Question 42

what type of monosaccharide is pyranose?

Answer 42

aldose

Question 43

what type of monosaccharide is furanose?

Answer 43

ketose

Question 44

cyclization of glucose & fructose & alcohol & carbonyl forms a ?

Answer 44

cyclic hemiacetal

Question 45

alpha and beta anomers interconverting in solution due to spontaneous reversible ring opening/ closing (either alpha or beta configuration at C1)

Answer 45

mutarotation

Question 46

if the OH on C1 is on top, then its ?

Answer 46

beta

Question 47

if the OH on C1 is down, then its ?

Answer 47

alpha

Question 48

When drawing the Haworth projection, anything to the left is drawn ____ and anything to the right is drawn ______

Answer 48

up; down

Question 49

the terminal in the Haworth projection, CH2OH, is up for _____ isomers and down for ______ isomers

Answer 49

D; L

Question 50

Monosaccharides are _____ agents

Answer 50

reducing

Question 51

Monosaccharides can be oxidized by relatively mild oxidizing agents such _____ ion (carbonyl group is oxidized to a carboxyl group)

Answer 51

cupric (Cu 3+)

Question 52

sugars capable of reducing cupric ions (such as glucose)

Answer 52

reducing sugars

Question 53

Disaccharides contain a _____ bond

Answer 53

glycosidic

Question 54

Disaccharides consist of two monosacchraides formed covalently by an ____

Answer 54

O-glycosidic bond

Question 55

How is an O-glycosidic bond formed?

Answer 55

when a hydroxyl group of one sugar molecule reacts with the anomeric carbon of the other (forms a glycoside0 (C1-C4 bonds)

Question 56

important Hexose derivatives: Glc = Fru = Gal = Man = Rib = Xyl = GlcN = GlcNAc = GalN = GalNAc = GlcA = GlcUA =

Answer 56

glucose fructose galactose mannose ribose xylose glucosamine N-acetylglucosamine galactosamine N-acetylgalactosamine gluconic acid glucuronic acid