MODULE 1A.2: Carbohydrate and Lipid Chemistry

Question 1

What is the empirical formula of carbohydrates?

Answer 1

(CH2O)n

Question 2

TRUE OR FALSE.

Glucose is the major metabolic fuel of all animals.

Answer 2

FALSE. Ruminant animals are exceptions.

Question 3

How much kilocalories can be produced from 1 gram of digestible carbohydrates?

Answer 3

4 kcal

Question 4

What is the composition of milk?

Answer 4

Lactose = Glucose + Galactose

Question 5

In excess, glucose is converted into its storage form __________.

Answer 5

Glycogen

Question 6

What happens to excess carbohydrates?

Answer 6

Converted into fat and stored in adipose tissue

Question 7

Which complex structures of carbohydrates are involved in cell-to-cell recognition?

Answer 7

Glycoproteins and glycolipids

Question 8

Carbohydrate-binding protein that mediates cell adhesion

Answer 8

Lectin

Question 9

Sugars that cannot be hydrolyzed into simpler carbohydrates

Answer 9

Monosaccharides

Question 10

Identify the number of carbons in each classification of carbohydrates:

1) Monosaccharide
2) Disaccharide
3) Oligosaccharide
4) Polysaccharide

Answer 10

1) 3-7 carbons
2) 2 monosaccharides
3) 3-10 monosaccharides
4) >10 monosaccharides

Question 11

What is the process of disaccharide formation and what is the bond formed?

Answer 11

Condensation; Glycosidic bond

Question 12

Substances consisting chiefly or entirely of a large number of similar units bonded together

Answer 12

Polymer

Question 13

Identify the following functional groups:

1) R-CO-R
2) R-CO-H
3) C=O
4) -COOH

Answer 13

1) Ketone
2) Aldehyde
3) Carbonyl group
4) Carboxyl group

Question 14

Monosaccharides that serve as intermediates in glycolysis

Answer 14

Dihydroxyacetone and glyceraldehyde

Question 15

Enumerate the classification of monosaccharides according to the number of carbons they contain.

Answer 15

1) Triose - 3 carbons
2) Tetrose - 4 carbons
3) Pentose - 5 carbons
4) Hexose - 6 carbons
5) Heptose - 7 carbons

Question 16

How are the atoms attached to an asymmetric carbon?

Answer 16

Covalent bonding

Question 17

In Haworth projections, what does it mean when a bond is bold or thickened?

Answer 17

It is the bond nearest to the viewer.

Question 18

What is the angle and shape of a monosaccharide?

Answer 18

109.5 degrees; tetrahedral

Question 19

Same molecular formula, different in the order of attachment of atoms

Answer 19

Constitutional Isomers

Question 20

Formed when hemiacetals or hemiketals react with a hydroyl group

Answer 20

Acetal and water

Question 21

Monosaccharides with a carboxyl group

Answer 21

Sugar (uronic) acids

Question 22

Formed when the carbonyl group of aldoses and ketoses is reduced to an alcohol

Answer 22

Sugar alcohol

Question 23

Formed when one or more hydroxyl groups of a monosaccharide is replaced by hydrogen

Answer 23

Deoxy sugar

Question 24

Isomer wherein the atoms are connected in the same order but differ in spatial arrangement

Answer 24

Stereoisomer

Question 25

Isomers that are non-superimposable mirror images of each other

Answer 25

Enantiomer

Question 26

Isomer that are not at all mirror images of each other

Answer 26

Diastereoisomer

Question 27

Isomers that differ in one of several asymmetric carbon atoms

Answer 27

Epimer

Question 28

Differ in a new asymmetric carbon atom or the anomeric carbon that is formed on link closure

Answer 28

Anomer