Deck 16: Carbohydrates

Question 1

Which of the following can be classified as a ketohexose? _

A) 1
B) 2
C) 3
D) 4
E) 1, 3, and 4

Answer 1

2

Question 2

Which of the following can be classified as an aldopentose?

A) 1
B) 2
C) 3
D) 4
E) 3 and 4

Answer 2

1

Question 3

Which of the following can be considered a polysaccharide?

A) sucrose
B) cellobiose
C) lactose
D) maltose
E) cellulose

Answer 3

cellulose

Question 4

Glucose can be classified as a:

A) monosaccharide
B) disaccharide
C) trisaccharide
D) polysaccharide
E) table sugar

Question 5

The linkage between the sugar units in starch are:

A) ( $\alpha$ )
B) ( $\beta$ )
C) ( $\gamma$ )
D)( $\delta$ )
E) none of these

Question 6

The acyclic structure of D-glucose is: The formula for ethyl $\alpha$ -D-glucopyranoside is:

A)
B)
C)
D)
E)

Question 7

Reduction of an optically active aldopentose with NaBH₄ gives an optically inactive alditol.The aldopentose could be:

A)
B)
C)
D)
E)

Question 8

Another name for the disaccharide, 4-O-( $\beta$ -D-galactopyranosyl)- $\beta$ -glucopyranose, is:

A) sucrose
B) cellobiose
C) lactose
D) maltose
E) amylose

Question 9

A 1,4- $\beta$ -linkage between two glucose units produces a disaccharide called:

A) dextrose
B) cellobiose
C) ribose
D) maltose
E) amylose

Question 10

A 1,4- $\alpha$ -linkage between two glucose units produces a disaccharide called:

A) dextrose
B) cellobiose
C) ribose
D) maltose
E) amylose

Question 11

Which of the following structures represent glycosides?

A) only 1
B) only 2
C) only 3
D) 1 and 2
E) 1, 2, and 3

Question 12

Hydrolysis of the disaccharide maltose produces:

A) sucrose
B) glucose
C) mannose
D) glucose and fructose
E) glucose and galactose

Question 13

The difference between the pyranose and furanose forms of a given aldohexose is:

A) the ring size
B) the number of the anomeric C
C) the type of functional groups
D) the number of functional groups
E) there is no difference

Question 14

The formula for maltose is: The acetal carbon(s) is(are):

A) C1
B) C1 and C1'
C) C1 and C4
D) C1'
E) C1' and C4'

Question 15

How many hydroxyl groups are present in the pyranose form of glucose?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 16

Which of the following can be classified as epimers?

A) 1 and 2
B) 1 and 3
C) 1 and 4
D) 3 and 4
E) none are epimers

Question 17

The anomeric carbon of is:

A) C1
B) C2
C) C3
D) C5
E) C6

Question 18

The Haworth projection formula for the pyranose form of $\beta$ -D-galactose is:

A)
B)
C)
D)
E)

Question 19

D-Glucose can exist in how many isomeric cyclic hemiacetal forms?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 20

Which of the following can be considered reducing sugars?

A) 1
B) 2
C) 3
D) 4
E) 1, 2, 3, and 4

Question 21

The product of the reaction below is:

A)
B)
C)
D)
E)

Question 22

How many stereogenic centers are in the $\beta$ -cyclic form of glucose?

A) 1
B) 2
C) 3
D) 4
E) 5

Question 23

Acid-catalyzed hydrolysis of gives:

A)
B)
C)
D)
E)

Question 24

The anomeric carbon in the structure below is numbered:

A) 1
B) 2
C) 3
D) 4
E) 5

Question 25

The term that best describes the relationship between is

A) conformers.
B) epimers.
C) enantiomers.
D) meso forms.
E) constitutional isomers.

Question 26

The product of is:

A)
B)
C)
D)
E)

Question 27

Reduction of which of the following aldoses provides an optically active alditol?

A) 1
B) 2
C) 3
D) 1 and 2
E) 3 and 4

Question 28

The following monosaccharide has ________ equatorial hydroxyl groups. _

A) 1
B) 2
C) 3
D) 4
E) 5

Question 29

D-Glucose reacts with acetic anhydride to produce:

A) ethers
B) esters
C) carboxylic acids
D) alcohols
E) aldehydes

Question 30

Starch is a polysaccharide that is found in many food sources.When starch is completely hydrolyzed, the monosaccharide that is produced is:

A) glucose
B) mannose
C) maltose
D) galactose
E) amylose

Question 31

The equilibrium rotation of an aqueous solution of $\alpha$ - and $\beta$ -D-glucose is +50°, and the rotations of the pure $\alpha$ and $\beta$ forms are +102° and +24°, respectively. Assuming no other forms are present, the percent $\alpha$ form at equilibrium is:

A) 66.7%
B) 50.0%
C) 22.5%
D) 33.3%
E) 24.0%

Question 32

Treatment of D-(+)-mannose with Fehling's reagent (Cu⁺²) gives:

A) an aldose
B) a ketose
C) an alditol
D) an aldonic acid
E) an aldaric acid

Question 33

Oxidation of optically active D-erythrose with nitric acid produces optically inactive meso-tartaric acid (below).What is the structure of D-erythrose?

A)
B)
C)
D)
E)

Question 34

The configurations at C2, C3, and C4 of are:

A) 2R, 3R, 4R
B) 2R, 3S, 4R
C) 2S, 3R, 4S
D) 2S, 3R, 4R
E) 2R, 3S, 4S

Question 35

The pyranose form of glucose is a(n):

A) linear aldehyde
B) cyclic hemiacetal
C) cyclic acetal
D) acyclic acetal
E) acyclic hemiacetal

Question 36

Hydrolysis of lactose gives:

A) glucose and galactose
B) glucose and fructose
C) mannose and fructose
D) galactose and fructose
E) allose and mannose

Question 37

A glycoside is formed upon reaction of glucopyranose with:

A) KMnO₄
B) HNO₃
C) Cu⁺²/OH^-
D) CH₃OH/H⁺
E) NaBH₄

Question 38

Which of the following reagents will convert the hydroxyl groups of a monosaccharide to methyl ethers?

A) H₂/Ni
B) Ag₂O/CH₃I
C) HNO₃
D) NaBH₄/H₂O
E) Br₂/H₂O

Question 39

The difference between $\alpha$ and $\beta$ -glucopyranose is:

A) the stereochemistry at the anomeric carbon
B) the number of carbons in the ring
C) the position of all the OH's on the ring
D) all of these reasons
E) none of these reasons

Question 40

A Newman projection formula for is:

A)
B)
C)
D)
E)

Question 41

The product of the following reaction sequence is:

A)
B)
C)
D)
E)

Question 42

Which of the following compounds will give a positive Tollens' test (silver mirror)?

A)
B)
C)
D)
E)

Question 43

Which of the following reagents will oxidize an aldose to an aldaric acid?

A) HNO₃
B) Br₂, H₂O
C) NaBH₄
D) PCC
E) Tollens' reagent

Question 44

The structure of an L-aldotetrose that would give an optically inactive alditol upon reduction with sodium borohydride (NaBH₄) is:

A)
B)
C)
D)
E)

Question 45

Treatment of methyl $\alpha$ -D-glucopyranose with silver oxide and iodomethane (Ag₂O, CH₃I) followed by hydrolysis (H₃O⁺) gives:

A)
B)
C)
D)
E)

Question 46

An intermediate in the following glycoside hydrolysis is:

A)
B)
C)
D)
E)