Ch. 8: Simple Carbohydrates Flashcards Preview

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Flashcards in Ch. 8: Simple Carbohydrates Deck (23):
1

Types of CHO (classification)?

Monosaccharides
Disaccharides
Oligosaccharides: 2-10 monosaccharides
Polysaccharides (glycans): > 10 monosaccharides

2

Classification of CHO: aldoses vs. ketoses?

Aldose: contains reactive aldehyde group

Ketose: contains reactive ketone group

3

3 C CHOs?

D-glycerose (D-glyceraldehyde)
D-erythrose

4

5 C CHOs?

D-lyxose
D-xylose
D-arabinose
D-ribose

5

Examples of aldoses?

D-galactose
D-mannose
D-glucose

6

Examples of ketoses?

Dihydroxyacetone
D-xylulose
D-ribulose
D-fructose
D-sedoheptulose

7

What types of sugar linkages can humans digest? Can't digest?

Can digest: alpha-linkage

Can't digest: beta-linkage

8

How to determine D & L sugars?

Config of asymmetric C farthest from CHO or C=O

L: OH on left
D: OH on right

9

What are stereoisomers?

Same chemical formula
Different position of OH on 1 or more asymmetric Cs

10

What are enantiomers?

Stereoisomers that are mirror images

11

What are epimers?

Stereoisomers w/different position of OH at only 1 asymmetric C

12

How to differ between alpha and beta config of CHOs in ring structure?

OH group on anomeric C

Alpha: OH on right (Fischer projection), BELOW ring
Beta: OH on left (Fischer projection), ABOVE ring

13

Alpha & beta D-glucose: which is more stable?

Beta-D-glucose (majority in water)

14

What is the major form of fructose? Differs in what situation?

Beta-D-fructopyranose (6 membered ring)

When phosphorylated, forms 5 membered ring (furanose)

15

CHO derivatives: sugar alcohols ➡️ describe?

Examples?

Carbonyl group reduced to OH group

Glycerol
D-sorbitol

16

CHO derivatives: sugar acids ➡️ describe?

Examples?

Carbonyl or OH group oxidized to COOH group

D-gluconate
Ascorbic acid

17

CHO derivatives: amino sugars ➡️ describe?

Examples?

Replace a OH group w/NH2 group

D-glucosamine
D-galactosamine

18

CHO derivatives: sugar phosphates ➡️ describe?

Examples?

Phosphoric esters of CHOs

Glucose-6-P
Ribose-5-P

19

CHO derivatives: deoxy sugars ➡️ describe?

Examples?

1 or more OH groups of pyranose or furanose substituted w/H

2-deoxy-alpha-D-ribose
Alpha-L-fucose

20

CHO derivatives: glycosides ➡️ describe?

Examples?

Condensation of anomeric OH group w/OH group of 2nd molecule (H2O eliminated)

Streptomycin (antibiotic)
Ouabain (cardiac glycoside)

21

How are disaccharides formed?

What are the 4 types (& which monosaccharides are they made from)?

2 monosaccharides linked via O-glycosidic bond

Sucrose = Glu + fru
Lactose = gal + Glu
Maltose = Glu + Glu
Lactulose = gal + fru
Trehalose
Cellobiose

22

Examples of homopolysaccharides? Important info about each?

Glycogen (animal, alpha(1➡️4 & 1➡️6) links)
Starch: amylose, amylopectin (plants, alpha(1➡️4 & 1➡️6) links)

Cellulose (beta(1➡️4) links)
Chitin (N-acetylglucosamine polymer)

23

Examples of heteropolysaccharides?

Proteoglycan (polysaccharide + protein)
Glycosphingolipids (polysaccharide + lipids)