Deck 17: Carbohydrates

Question 1

The following structure is shown in what form?  

A)a D form
B)an L form
C)neither D nor L
D)both D and L

Answer 1

an L form

Question 2

The carbohydrate below may be classified as a(n)________.

A)aldopentose
B)aldohexose
C)ketopentose
D)ketohexose

Answer 2

ketopentose

Question 3

Which of the following monosaccharides is a ketohexose?

A)ribose
B)glucose
C)galactose
D)fructose

Answer 3

fructose

Question 4

Which of the following statements about chiral carbons is correct?

A)A chiral carbon is one that has four different groups attached.
B)A chiral carbon is one that determines the possibility of stereoisomerism.
C)A chiral carbon can be an interior carbon.
D)There is more than one correct response.

Question 5

A short description of a stereoisomer would be?

A)Stereoisomers are all of the isomers for compounds that can have in excess of two isomers.
B)Stereoisomers are those compounds that can have two isomers that are straight chain and the right side is different from the left side.
C)Stereoisomers are two isomers that resemble each other in the sense that one of the isomers is the mirror image of the other.
D)There is more than one correct response.

Question 6

How many chiral carbons are contained in ribose, which is shown below?

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

Question 7

Which of the following is NOT a carbohydrate?

A)amylopectin
B)deoxyribose
C)glycogen
D)cellulose

Question 8

How many stereoisomers of an aldopentose exist?

A)2
B)4
C)6
D)8

Question 9

Carbohydrates which contain two sugar units chemically linked together are called a(n)_____ .

A)monosaccharides
B)disaccharides
C)trisaccharides
D)polysaccharides

Question 10

Which carbon atoms in the following structure are correctly called chiral carbon atoms?

A)carbons 1 and 2
B)carbons 2 and 3
C)carbons 3 and 4
D)carbons, 1, 2, 3, and 5

Question 11

Which of the following choices is a carbohydrate?

A)progestin
B)formaldehyde
C)galactose
D)hexamide

Question 12

Which of the following groups are expected to be found in carbohydrates?

A)alcohol
B)thiol
C)methyl
D)amide

Question 13

What characteristic of carbohydrates is not commonly found in the previously studied classes of compounds?

A)Carbohydrates are unique in that they do not contain any nitrogen.
B)Carbohydrates often contain a functional group on each carbon.
C)The carbohydrate class is the only class composed solely of cyclic compounds.
D)There is more than one correct response.

Question 14

Which of the following can exist in enantiomers?

A)
B)
C)
D)all of these choices

Question 15

The following structure is shown in what form?

A)a D form
B)an L form
C)neither D nor L
D)both D and L

Question 16

The simplest carbohydrates are called  _____ .

A)monosaccharides
B)disaccharides
C)polysaccharides
D)oligosaccharides

Question 17

Which of the following compounds is the enantiomer of the structure shown below?

A)
B)
C)
D)

Question 18

Which form of monosaccharides is preferred by human cells?

A)D
B)L
C)both
D)neither

Question 19

Which of the following is a disaccharide?

A)glucose
B)fructose
C)galactose
D)maltose

Question 20

How many chiral carbons are contained in the following structure?

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

Question 21

Of the 16 aldohexoses, how many exist in the D form?

A)8
B)16
C)4
D)6

Question 22

A monosaccharide used to form nucleic acids is _____ .

A)glucose
B)galactose
C)ribose
D)maltose

Question 23

The body stores carbohydrates as _____ .

A)cellulose
B)glycogen
C)sucrose
D)starch

Question 24

A sugar present in honey in a 1:1 ratio with glucose is _____ .

A)fructose
B)maltose
C)sucrose
D)galactose

Question 25

The sweetest of the common sugars is _____ .

A)fructose
B)glucose
C)galactose
D)maltose

Question 26

Which of the following sugars fails to give a positive Benedict's test?

A)glucose
B)galactose
C)lactose
D)sucrose

Question 27

A component of lactose is the sugar _____ .

A)ribose
B)deoxyribose
C)fructose
D)galactose

Question 28

Maltose upon hydrolysis yields

A)glucose and galactose.
B)glucose and fructose.
C)only glucose.
D)Hydrolysis does not occur

Question 29

Of the monosaccharides, which is the most important nutritionally?

A)ribose
B)glucose
C)galactose
D)fructose

Question 30

Structurally, glycogen is most similar to _____ .

A)amylose
B)amylopectin
C)cellulose
D)sucrose

Question 31

The disaccharide formed during the digestion of starch is _____ .

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

Question 32

The linkage between the two monosaccharide units of a disaccharide is a

A)hemiacetal linkage.
B)alpha linkage.
C)ester linkage.
D)glycosidic linkage.

Question 33

The cyclic form of glucose has how many possible stereoisomers compared to the noncyclic form?

A)double
B)triple
C)reduced by half
D)remains the same

Question 34

A carbohydrate present in the blood is _____ .

A)sucrose
B)glucose
C)fructose
D)maltose

Question 35

Which polysaccharide usually makes up 80-90% of plant starch?

A)chitin
B)amylopectin
C)heparin
D)hyaluronic acid

Question 36

Sugars which contain an aldehyde group that can be oxidized are called _____ .

A)reducing sugars
B)oxidizing sugars
C)glycosides
D)simple sugars

Question 37

Which of the following carbohydrates yields invert sugar upon hydrolysis?

A)fructose
B)sucrose
C)starch
D)glycogen

Question 38

A polysaccharide containing β (1 → 4)linkages is _____ .

A)cellulose
B)glycogen
C)amylose
D)amylopectin

Question 39

The cyclic form of glucose results from the formation of a(n)  _____ .

A)ester
B)acetal
C)hemiacetal
D)amide

Question 40

The cyclic form of ____ contains a furanose ring.

A)glucose
B)maltose
C)galactose
D)fructose

Question 41

What is the name of the following sugar?

A)sucrose
B)maltose
C)lactose
D)xylobiose

Question 42

Glyceraldehyde is the simplest member of the carbohydrates and is shown below.  What is the total number of functional groups that this molecule contain?

A)0
B)1
C)2
D)3

Question 43

Artificial sweeteners should be avoided by people suffering from phenylketonuria (PKU)due to their body's inability to metabolize ____ properly.

A)aldehydes
B)phenols
C)ketones
D)phenylalanine

Question 44

Carbohydrates serve a number of important functions in our bodies.  Which of the following is NOT one of those functions?

A)They provide energy through their oxidation.
B)They serve as a carbon supply for the synthesis of cell components.
C)They serve as a way to store chemical energy.
D)They are used as structural elements in cell walls.

Question 45

The structure given below has what type of glycosidic linkage?

A)α (1 → 6)
B)β (1 → 4)
C)β (1 → 6)
D)α (1 → 4)

Question 46

The maximum number of stereoisomers for a compound containing 6 chiral carbon atoms is  _____ .

A)6
B)16
C)64
D)132

Question 47

Which is a test for the presence of starch?

A)Benedict's test
B)exposure to iodine
C)sweet taste
D)acid-base titration

Question 48

When the compound below  is treated with Benedict's reagent, that is the product of the reaction?

A)
B)
C)
D)no reaction

Question 49

What is the major difference between glucose and sorbitol?

A)Glucose has 6 carbons; sorbitol has 5 carbons.
B)Glucose has 6 carbons; sorbitol has 7 carbons.
C)Glucose contains hydroxy groups; sorbitol does not contain hydroxy groups.
D)Glucose contains an aldehyde carbon; sorbitol has an alcohol carbon in that location.

Question 50

The structure given below has what type of glycosidic linkage?

A)α (1 → 6)
B)β (1 → 4)
C)β (1 → 6)
D)α (1 → 4)

Question 51

The following two monosaccharides form a disaccharide by forming a bond between the two carbons indicated with an asterisk (*).  What type of linkage results?

A)
B)
C)
D)

Question 52

The structure shown in what anomeric form?

A)α
B)β
C)cis
D)trans

Question 53

What is the name of the following sugar?

A)sucrose
B)maltose
C)lactose
D)xylobiose

Question 54

Which of the following correctly describes the structure shown?

A)aldopentose with 5 chiral carbon atoms
B)aldopentose with 3 chiral carbon atoms
C)ketopentose with 5 chiral carbon atoms
D)ketopentose with 3 chiral carbon atoms

Question 55

What is the name of the following sugar?

A)sucrose
B)maltose
C)lactose
D)xylobiose

Question 56

What polysaccaride would NOT exhibit the following type of linkage for all or a major portion of its structure?

A)amylose
B)amylopectin
C)glycogen
D)cellulose

Question 57

The structure shown is in what anomeric form?

A)α
B)β
C)cis
D)trans

Question 58

Monosaccharides and disaccharides both have a sweet taste. What taste does a polysaccharide have?

A)sweet
B)sour
C)bitter
D)tasteless

Question 59

Many commercials sell fiber supplements but you do not have the money to buy them.  Which of the following is a poor source of fiber?

A)steak
B)beans
C)carrots
D)banana

Question 60

The following structure is best represented as

A)pyranose with a beta hydroxy group.
B)pyranose with an alpha hydroxy group.
C)furanose with a beta hydroxy group.
D)furanose with an alpha hydroxy group.

Question 61

Cellulose does not contribute to the caloric intake in humans.

Question 62

Cellulose is a polysaccharide composed of glucose units.

Question 63

One function of carbohydrates is to form structural elements of some cells and tissues.

Question 64

There is no biological significance attributed to stereoisomers.

Question 65

All sugars are ketoses.

Question 66

A characteristic of carbohydrates is that a carbonyl carbon is usually incorporated in their structures.

Question 67

Starch is made up of 50 to 100 glucose units.

Question 68

The hydrolysis of cellulose and starch would give the same monosaccharide.

Question 69

Carbohydrates have their name because the ratio of carbon to water is always 1:1.

Question 70

In order for molecules to be mirror images, there must be at least one carbon that does not have duplicate groups attached.

Question 71

Polysaccharides usually give a negative Benedict's test.

Question 72

There are currently several artificial sweeteners on the market.  Which of the following is NOT one of those artificial sweeteners?

A)maltose
B)aspartame
C)sorbitol
D)acesulfame-K

Question 73

Molecules that are mirror images are enantiomers.

Question 74

CH₄ could exist as a pair of enantiomers.

Question 75

Polysaccharides tend to be very sweet.

Question 76

The two forms of the glucose ring resulting from the substituents on the C-1 carbon are anomers.

Question 77

sec-butyl alcohol has two stereoisomers.

Question 78

One of the characteristics of organic molecules is that they all can exist as stereoisomers.

Question 79

A molecule with 3 chiral atoms would have 6 stereoisomers.

Question 80

All aldopentoses have 5 carbon atoms.