carbohydrate structure

Question 1

constitutional isomers

Answer 1

order of atoms change

Question 2

constitutional isomers are

Answer 2

tautomers

Question 3

fisher projections are

Answer 3

linear versions of carbohydrates

Question 4

stereoisomers

Answer 4

have the same connectivity but different spatial organizations

Question 5

types of stereoisomers

Answer 5

configurational isomers and conformational isomers

Question 6

configurational isomers

Answer 6

have chiral carbons

Question 7

types of configurational isomers

Answer 7

diastereomers and enantiomers

Question 8

enantiomers

Answer 8

are mirror images at all chiral centers

Question 9

diastereomers

Answer 9

have multiple chiral centers; not all chiral carbons are mirror images

Question 10

D/L nomenclature is determined by

Answer 10

direction of last chiral carbon’s -OH group

Question 11

haworth projections

Answer 11

are the cyclical versions of carbohydrates

Question 12

steps to convert from fisher to haworth projections

Answer 12

1. choose ring
2. the carbonyl carbon goes 1 position clockwise from the oxygen
3. number carbons clockwise
4. the =O becomes OH, and UP is beta while DOWN is alpha

Question 13

types of diastereomers

Answer 13

epimers and anomers

Question 14

anomers differ at

Answer 14

the anomeric carbon only (i.e. alpha vs. beta)

Question 15

epimers differ

Answer 15

at any other carbon than the anomeric carbon (i.e. same alpha or beta but different somewhere else)

Question 16

conformational isomers

Answer 16

have reversible rotation changes

e.g. nucleotides

Question 17

glycosides

Answer 17

are formed when one or more hydroxyls are replaced

Question 18

fucose

Answer 18

• galactose derivative - methyl added onto C-
• only L-monosaccharide made and used by animals
• part of A/B/O blood antigens

Question 19

excess free fucose in blood

Answer 19

liver damage

cancer

diabetes

heart disease

Question 20

modified monosacchrides - phosphorylation

phosphates have _____ linkages

Answer 20

ester

• sugar phosphate backbone in nucleic acids
• important reactive intermediates in carbohydrate metabolism
• adds negative charge
• phosphate from ATP
• name tells where to put the phosphate

Question 21

modified monosaccharides - oxidation

• reducing sugars are:
• 2 step process, makes:
• an antiquated:

Answer 21

• oxidized at the carbonyl (anomeric carbon)
• acids and lactones
• diabetes urine test

Question 22

reducing sugars are

Answer 22

monosaccharides

Question 23

modified monosacchardies - reduction

• reduction at the carbonyl makes:
• ______ can cause cataracts it if accumaultes in the lens of the eye

Answer 23

• alditols
• sorbitol

Question 24

modified monosaccharides - amino sugars

• found in branched:
• common additions to:
• ___ - linked glycosides

Answer 24

• polysaccharides (e.g. cell walls)
• proteins
• N-linked

Question 25

modified monosaccharides - methylation * ____ - linked * same reaction that creates _________ , but with a non-sugar

Answer 25

* O-linked * polysaccharides

Question 26

some important toxins are

Answer 26

O-linked glycosides

Question 27

essential monosaccharides

Answer 27

_Regular monosaccharides:_ * D-Glucose * D-Galactose * D-Mannose * D-Xylose _the oddball:_ * L-Fucose _Amino sugars:_ * GlcNAc * GalNAc * Sialic Acid

Question 28

Maltose: anomeric carbons:

Answer 28

disaccharide consisting of 2 glucoses 1 and 4

Question 29

lactose anomeric carbons:

Answer 29

disaccharide consisting of 1 galactose and 1 glucose 1 galactose and 4 glucose

Question 30

sucrose anomeric carbons

Answer 30

disaccharide consisting of 1 glucose and 1 fructose 1 glucose and 2 fructose

Question 31

roles for polysaccharides

Answer 31

1. glucose storage (alpha linkages) 2. structure (beta-linkages) e.g cellulose 3. protein diversity (N-linkages through Asn) (O-linkages through Ser or Thr)

Question 32

is amylose branched or unbranched

Answer 32

unbranched

Question 33

one structural polysaccharides essentially is universal:

Answer 33

chitin

Question 34

_glycoproteins:_ 1. protein ____ sugar (by weight) 2. on membranes, involved in: 3. on soluble protesin, involved in:

Answer 34

1. \> 2. cell adhesion 3. cell signaling

Question 35

_glycosaminoglycans:_ 1. sugar ____ protein (by weight) 2. repeating ____ units 3. sugar component of proteoglycans are involved in:

Answer 35

1. \> 2. dissacharide 3. cartilage, blood clotting, chitin

Question 36

_mucins:_ 1. sugar ____ protein (by weight) 2. more complex patterns than ____ repeats 3. lubrication = ____ + \_\_\_\_

Answer 36

1. \> 2. disaccharide 3. protection + hydration

Question 37

glycolipids decorate cell ____ and are used to recognize \_\_\_\_

Answer 37

membranes self/others (ABO blood typing)

Question 38

difference between O-B blood types

Answer 38

addition of a galactose

Question 39

difference between O-A blood types

Answer 39

acetyl-galactose amine group

Question 40

difference between A-B blood types

Answer 40

difference is only an N-linked acetyl