Question 1

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

Accepted Answer

Catalysis of metabolic reactions

Question 2

What is the general formula for a monosaccharide with $$n$$ carbon atoms?

Accepted Answer

$$C_n(H_2O)_n$$

Question 3

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

Accepted Answer

Aldoses have an aldehyde group, while ketoses have a ketone group

Question 4

Which of the following best describes an epimer?

Accepted Answer

A stereoisomer that differs in configuration at only one carbon atom other than the anomeric carbon

Question 5

Which of the following is true regarding the cyclization of monosaccharides?

Accepted Answer

Cyclization creates a new asymmetric center called the anomeric center

Question 6

Which of the following is a correct statement about the difference between D- and L- enantiomers of monosaccharides?

Accepted Answer

They differ in the configuration of the asymmetric carbon farthest from the carbonyl group

Question 7

Which of the following is a property of diastereomers?

Accepted Answer

They are optical isomers that are not mirror images

Question 8

Which of the following is a correct description of a glycosidic bond?

Accepted Answer

A bond formed by the elimination of water between the anomeric carbon of a cyclic saccharide and the hydroxyl group of another compound

Question 9

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

Accepted Answer

D-Glucitol (sorbitol)

Question 10

Which of the following is true about the formation of glycosidic bonds in disaccharides?

Accepted Answer

The reaction is thermodynamically unfavored and requires activation, such as by UDP-galactose

Question 11

Which of the following is a homopolysaccharide found in plant cell walls?

Accepted Answer

Cellulose

Question 12

Which of the following correctly describes the branching in amylopectin and glycogen?

Accepted Answer

Both amylopectin and glycogen have $$\alpha(1 \rightarrow 6)$$ branches, but glycogen has shorter and more frequent branch points

Question 13

Which of the following is a major structural polysaccharide in the exoskeleton of arthropods?

Accepted Answer

Chitin

Question 14

Which of the following is a function of glycosaminoglycans in vertebrates?

Accepted Answer

Structural support and lubrication

Question 15

Which of the following statements about peptidoglycans is correct?

Accepted Answer

They are found in the cell walls of gram-positive bacteria and consist of alternating N-acetylglucosamine and N-acetylmuramic acid crosslinked by peptides

Question 16

Which of the following is true about glycoproteins?

Accepted Answer

They are proteins with covalently attached oligosaccharide or polysaccharide chains

Question 17

Which of the following is a correct statement about the ABO blood group antigens?

Accepted Answer

They are O-linked glycoproteins

Question 18

Which of the following is a correct description of the role of erythropoietin (EPO)?

Accepted Answer

It is a glycoprotein hormone that stimulates red blood cell production

Question 19

Which of the following is true about the configuration of the anomeric carbon in cyclic monosaccharides?

Accepted Answer

It determines whether the sugar is in the $$\alpha or$$ $$\beta$$ form

Question 20

Which of the following is a correct statement about conformational isomers of pyranose rings?

Accepted Answer

They have the same stereochemical configuration but differ in three-dimensional conformation, such as chair and boat forms

Carbohydrates: Structure, Classification, and Biological Roles

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