Chapter 10: Carbohydrates

Question 1

Monosaccharides are […] or […] that have two or more […] groups.

Answer 1

ketones; aldehydes; hydroxyl

Question 2

List the smallest monosaccharides (2):

Answer 2

1. dihydroxyacetone

2. D/L glyceraldehyde

Question 3

How many carbons are within the smallest monosaccharides?

Answer 3

three

Question 4

Dihydroxyacetone is called a […] while D/L glyceraldehyde are known as […].

Answer 4

ketose; aldoses

Question 5

Stereoisomers vs constitutional isomers:

Answer 5

stereoisomers– isomers that differ in spatial arrangement

constitutional isomers– differ in how the atoms are ordered

Question 6

What type of stereoisomer are L/D glyceraldehyde?

Answer 6

enantiomers

Question 7

What are the categories of isomers?

Answer 7

1. constitutional isomers
2. stereoisomers
   2a. enantiomers
   2b. diastereoisomers
   ba. epimers
   bb. anomers

Question 8

The designation of alpha means that the hydroxyl group attached to C-1 is […]; beta means that it is […].

Answer 8

below the plane of the ring; above the plane of the ring

Question 9

In the chair form, the substituents on the ring carbon atoms have two orientations: […] and […].

Axial bonds are […] to the average plane of the ring, whereas equatorial bonds are […].

Answer 9

axial; equatorial

perpendicular; parallel

Question 10

Axial substituents […] each other if they emerge on the same side of the ring. In contrast, equatorial substituents are […].

Answer 10

sterically hinder; less crowded

Question 11

The biochemical properties of monosaccharides can be modified by reaction with other molecules. What are the common reactants?

Answer 11

1. alcohols
2. amines
3. phosphates

Question 12

Glycosidic bond is a bond formed between…

Answer 12

anomeric carbon atom of glucose and the oxygen atom of an alcohol

Question 13

Oligosaccharides are built by…

Answer 13

the linkage of two or more monosaccharides by O-glycosidic bonds

Question 14

Which enzymes act to synthesize olgiosaccharides?

Answer 14

glycosyltransferases

Question 15

What are the abundant disaccharides we encounter?

Answer 15

sucrose, lactose, maltose

Question 16

Beta-1,4 glycosidic linkage forms:

The two monomers brought together are:

Answer 16

lactose

galactose and glucose

Question 17

Alpha-1,4-glycosidic linkage forms:

The two monomers that form this are:

Answer 17

maltose

glucose and glucose

Question 18

Role of large polymeric oligosaccharides:

Answer 18

1. energy storage

2. maintaining the structural integrity of an organism

Question 19

What is the most common homopolymer in animal cells? What is its main role?

Answer 19

glycogen– the storage of glucose

Question 20

The most common homopolymer in plants is […] which comes in two forms […] and […].

Answer 20

starch; amylose; amylopectin

Question 21

Amylose vs amylopectin:

Answer 21

As– unbranched type of starch; glucose residues in an alpha-1,4 linkage

Ap: branched form of starch; one alpha-1,6 linkage per 30 alpha-1,4 linkages

Question 22

Amylopectin, amylose, and glycogen are rapidly hydrolyzed by […] secreted by […] and the […].

Answer 22

alpha-amylase; salivary glands; pancreas