Question 1

Which of the following is NOT a function of carbohydrates in biological systems?

Accepted Answer

Catalysis of metabolic reactions

Question 2

A monosaccharide is defined as a simple sugar with how many carbon atoms?

Accepted Answer

3 to 9

Question 3

Which general formula best represents a carbohydrate with $$n$$ carbon atoms?

Accepted Answer

$$C_n(H_2O)_n$$

Question 4

Which of the following statements about aldoses and ketoses is correct?

Accepted Answer

Aldoses contain an aldehyde group and ketoses contain a ketone group

Question 5

Which property makes monosaccharides chiral molecules?

Accepted Answer

Presence of a carbon atom with four different substituents

Question 6

Which projection is most commonly used to represent the stereochemistry of monosaccharides?

Accepted Answer

Fischer projection

Question 7

D-Threose and L-Erythrose are examples of which type of stereoisomer?

Accepted Answer

Diastereomers

Question 8

Which statement about ketotetrose erythrose is correct?

Accepted Answer

It has only two enantiomers and no diastereomers

Question 9

Cyclization of monosaccharides creates a new asymmetric center called the anomeric carbon. The resulting stereoisomers are called:

Accepted Answer

Anomers

Question 10

Which of the following pairs are epimers, differing only in the configuration at one carbon atom?

Accepted Answer

Glucose and mannose

Question 11

Which type of isomerism is observed between the chair and boat forms of $$\beta-D-$$glucopyranose?

Accepted Answer

Conformational isomerism

Question 12

Which derivative of glucose is formed by reduction of its carbonyl group?

Accepted Answer

D-glucitol (sorbitol)

Question 13

Which of the following is a carbohydrate in which at least one hydroxyl group has been replaced by an amine group?

Accepted Answer

D-glucosamine

Question 14

The elimination of water between the hydroxyl group of the anomeric carbon of a cyclic saccharide and the hydroxyl group of another compound yields:

Accepted Answer

An O-glycosidic bond

Question 15

Which of the following is NOT a major feature used to distinguish disaccharides?

Accepted Answer

The number of phosphate groups attached

Question 16

In the biosynthesis of lactose, which activated sugar is required for glycosidic bond formation?

Accepted Answer

UDP-galactose

Question 17

Which of the following polysaccharides is a linear homopolymer of $$\beta-D-$$glucose connected by $$\beta-1$$,4 linkages?

Accepted Answer

Cellulose

Question 18

Which statement best describes the difference between amylopectin and glycogen?

Accepted Answer

Glycogen has higher molecular weight and more frequent branch points than amylopectin

Question 19

Which of the following is a homopolymer of N-acetyl-D-glucosamine and is a major structural component of arthropod exoskeletons?

Accepted Answer

Chitin

Question 20

Which type of glycoprotein linkage involves attachment of the oligosaccharide chain to the side chain amide group of an asparagine residue?

Accepted Answer

N-linked

Carbohydrates: Structure, Classification, and Biological Roles

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