Question 1

Suggest a reason why sorbitol prevents water loss in candy.

Accepted Answer

Moisture loss is pre...

Question 2

Raffinose, the most abundant trisaccharide in nature, occurs in whole grains and numerous vegetables. It is the F1F1F1S1F1F1F10-galactosyl derivative of sucrose. Is raffinose a reducing or nonreducing sugar?

Accepted Answer

Raffinsoe is a reducing sugar because the galactosyl ring can open.

Question 3

Which of the following sugars lacks a chiral center?

Accepted Answer

A)   Glucose
B)   Glyceraldehyde
C)   Dihydroxyacetone
D)   Ribose
E)   FructoseF) A) and C)
G) C) and D)

Question 4

The polymer chains of glycosaminoglycans are widely spread apart and bind large amounts of water. What functional groups of the polymer are responsible for this phenomenon?

Accepted Answer

GAGs are widely spread apart a...

Question 5

Which of the following is a glycoside?

Accepted Answer

A)   
B)  
C)  
D)  
E)  F) A) and E)
G) A) and D)

Question 6

The production of the glycan components of each type of glycoprotein as a series of slightly different forms is referred to as __________

Accepted Answer

A)   glycoformation
B)   glycolation
C)   microheterogeneity
D)   posttranslational modification
E)   alternative splicingF) A) and B)
G) C) and D)

Question 7

Which of the following carbohydrates does not belong to the family of naturally occurring sugars?

Accepted Answer

A)  
B)  
C)  
D)  
E)   F) B) and E)
G) B) and D)

Question 8

The three most common homoglycans found in nature are cellulose, starch, and __________.

Accepted Answer

A)   amylose
B)   lactose
C)   fructose
D)   glycogen
E)   sucroseF) None of the above
G) A) and C)

Question 9

Which of the following compounds is an aldaric acid?

Accepted Answer

A)  
B)  
C)  
D)  
E)  F) A) and B)
G) A) and C) E

Question 10

What is an enediol?

Accepted Answer

An enediol is the intermediate...

Question 11

Phosphate esters can form at position 2 to 6 of an aldohexose but not in position 1. Explain.

Accepted Answer

Phosphate esters can form at p...

Question 12

The simplest chiral aldose has three carbon atoms, but the simplest chiral ketose has four carbons. Explain. Include structures in your answer.

Accepted Answer

Chiral molecules must have a carbon cent...

Question 13

Toxic compounds in plants frequently have bitter tastes that are detectable at very low concentrations. The sweet taste of carbohydrates is only detectable at much higher levels. Can you suggest a reason why this is true?

Accepted Answer

Certain plants contain toxic molecules t...

Question 14

The two polysaccharides used to store glucose as an energy reserve are starch and __________.

Accepted Answer

A)   glycogen
B)   cellulose
C)   fructose
D)   sucrose
E)   maltoseF) A) and D)
G) B) and D)

Question 15

There are two chemically distinct forms of glucose. How is it possible for a single molecule to behave as two distinct molecules?

Accepted Answer

Glucose can form a ring and in so doing ...

Question 16

What sugar is produced by the epimerization of galactose?

Accepted Answer

Three sugars are possible. Talose is the sugar produced by the epimerization of galactose at C2. The C4 epimer is glucose, and the C3 epimer is galactose.

Question 17

In an aldohexopyranose how many methyl groups will be incorporated on treatment with methyl iodide?

Accepted Answer

A)   One
B)   Two
C)   Three
D)   Four
E)   FiveF) B) and D)
G) A) and B)

Question 18

Why is it advantageous for a plant toxin to elicit a bitter taste when an animal eats the plant rather than a bland or sweet taste?

Accepted Answer

A bitter taste is sufficiently unpleasan...

Question 19

Classify D-glucose and D-mannose as enantiomers, diastereomers, epimers, or an aldose ketose pair.

Accepted Answer

D-glucose ...

Question 20

How does glycosylation improve the water solubility of a water-insoluble molecule?

Accepted Answer

The OH groups of the sugar int...

Exam 7: Carbohydrates

Suggest a reason why sorbitol prevents water loss in candy.

Correct AnswerverifiedMoisture loss is pre...View AnswerShow Answer

Raffinose, the most abundant trisaccharide in nature, occurs in whole grains and numerous vegetables. It is the -galactosyl derivative of sucrose. Is raffinose a reducing or nonreducing sugar?

Correct AnswerverifiedRaffinsoe is a reducing sugar because the galactosyl ring can open.

Which of the following sugars lacks a chiral center?

Correct AnswerverifiedShow Answer

The polymer chains of glycosaminoglycans are widely spread apart and bind large amounts of water. What functional groups of the polymer are responsible for this phenomenon?

Correct AnswerverifiedGAGs are widely spread apart a...View AnswerShow Answer

Which of the following is a glycoside?

Correct AnswerverifiedShow Answer

The production of the glycan components of each type of glycoprotein as a series of slightly different forms is referred to as __________

Correct AnswerverifiedShow Answer

Which of the following carbohydrates does not belong to the family of naturally occurring sugars?

Correct AnswerverifiedShow Answer

The three most common homoglycans found in nature are cellulose, starch, and __________.

Correct AnswerverifiedShow Answer

Which of the following compounds is an aldaric acid?

Correct AnswerverifiedE

What is an enediol?

Correct AnswerverifiedAn enediol is the intermediate...View AnswerShow Answer

Phosphate esters can form at position 2 to 6 of an aldohexose but not in position 1. Explain.

Correct AnswerverifiedPhosphate esters can form at p...View AnswerShow Answer

The simplest chiral aldose has three carbon atoms, but the simplest chiral ketose has four carbons. Explain. Include structures in your answer.

Correct AnswerverifiedChiral molecules must have a carbon cent...View AnswerShow Answer

Toxic compounds in plants frequently have bitter tastes that are detectable at very low concentrations. The sweet taste of carbohydrates is only detectable at much higher levels. Can you suggest a reason why this is true?

Correct AnswerverifiedCertain plants contain toxic molecules t...View AnswerShow Answer

The two polysaccharides used to store glucose as an energy reserve are starch and __________.

Correct AnswerverifiedShow Answer

There are two chemically distinct forms of glucose. How is it possible for a single molecule to behave as two distinct molecules?

Correct AnswerverifiedGlucose can form a ring and in so doing ...View AnswerShow Answer

What sugar is produced by the epimerization of galactose?

Correct AnswerverifiedThree sugars are possible. Talose is the sugar produced by the epimerization of galactose at C2. The C4 epimer is glucose, and the C3 epimer is galactose.

In an aldohexopyranose how many methyl groups will be incorporated on treatment with methyl iodide?

Correct AnswerverifiedShow Answer

Why is it advantageous for a plant toxin to elicit a bitter taste when an animal eats the plant rather than a bland or sweet taste?

Correct AnswerverifiedA bitter taste is sufficiently unpleasan...View AnswerShow Answer

Classify D-glucose and D-mannose as enantiomers, diastereomers, epimers, or an aldose ketose pair.

Correct AnswerverifiedD-glucose ...View AnswerShow Answer

How does glycosylation improve the water solubility of a water-insoluble molecule?

Correct AnswerverifiedThe OH groups of the sugar int...View AnswerShow Answer

Correct Answer
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Moisture loss is pre...
View Answer

Correct Answer
verified
Raffinsoe is a reducing sugar because the galactosyl ring can open.

Correct Answer
verified

Correct Answer
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GAGs are widely spread apart a...
View Answer

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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E

Correct Answer
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An enediol is the intermediate...
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Correct Answer
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Phosphate esters can form at p...
View Answer

Correct Answer
verified
Chiral molecules must have a carbon cent...
View Answer

Correct Answer
verified
Certain plants contain toxic molecules t...
View Answer

Correct Answer
verified

Correct Answer
verified
Glucose can form a ring and in so doing ...
View Answer

Correct Answer
verified
Three sugars are possible. Talose is the sugar produced by the epimerization of galactose at C2. The C4 epimer is glucose, and the C3 epimer is galactose.

Correct Answer
verified

Correct Answer
verified
A bitter taste is sufficiently unpleasan...
View Answer

Correct Answer
verified
D-glucose ...
View Answer

Correct Answer
verified
The OH groups of the sugar int...
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