Question 1

Which of the following is NOT one of the four major classes of biomacromolecules found in living organisms?

Accepted Answer

Vitamins

Question 2

The general formula for a monosaccharide is given by $$ (CH_2O)_n . $$Which of the following best describes a hexose?

Accepted Answer

$$ n = 6 $$

Question 3

Which functional group is present in all monosaccharides and is essential for their classification as either aldoses or ketoses?

Accepted Answer

Carbonyl group

Question 4

Which process allows a linear monosaccharide to form a cyclic structure in aqueous solution?

Accepted Answer

Intramolecular hemiacetal or hemiketal formation

Question 5

In the context of carbohydrate stereochemistry, what distinguishes a D-sugar from an L-sugar?

Accepted Answer

The orientation of the hydroxyl group on the penultimate carbon

Question 6

Which of the following is the correct sequence for converting a monosaccharide from its linear form to its most stable chair conformation?

Accepted Answer

Fisher $$\rightarrow$$ Haworth $$\rightarrow$$ Chair

Question 7

Which of the following statements about glycosidic bonds is TRUE?

Accepted Answer

They link monosaccharides to form oligo- and polysaccharides.

Question 8

Which of the following is a common monosaccharide found in mammals and is represented by a blue square in glycan symbol nomenclature?

Accepted Answer

N-Acetylglucosamine (GlcNAc)

Question 9

Which of the following best describes the role of carbohydrates in cellular signaling?

Accepted Answer

They serve as recognition molecules on cell surfaces.

Question 10

A patient is unable to digest lactose due to a deficiency in the enzyme lactase. Which type of bond in lactose is not being hydrolyzed?

Accepted Answer

$$ \beta(1 \rightarrow 4) $$ glycosidic bond

Question 11

Which of the following is TRUE regarding the equilibrium between linear and cyclic forms of glucose in solution?

Accepted Answer

Both forms exist, but the cyclic form predominates.

Question 12

Which of the following is a pentose commonly found in mammalian cells?

Accepted Answer

D-Xylose

Question 13

Which of the following is the correct Haworth projection for the $$ \beta -$$isomer of the pyranose form of D-Galactose?

Accepted Answer

The anomeric hydroxyl group is equatorial and points up.

Question 14

Which chair conformation represents the MOST stable form of $$ \beta -D-$$Galactose?

Accepted Answer

The conformation with bulky groups in equatorial positions.

Question 15

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

Accepted Answer

Catalyzing chemical reactions

Question 16

Which of the following correctly matches a monosaccharide with its symbol in the Symbol Nomenclature for Glycans (SNFG)?

Accepted Answer

D-Mannose: green circle

Question 17

Which of the following statements about the formation of a hemiketal is correct?

Accepted Answer

It results from the reaction of a ketone with an alcohol.

Question 18

Which of the following is a direct consequence of the stereochemistry of monosaccharides in biological systems?

Accepted Answer

Only one stereoisomer (usually D-form) is metabolized by most organisms.

Question 19

Which of the following best explains why polysaccharides can quickly become complex in structure?

Accepted Answer

Glycosidic bonds can form between multiple hydroxyl groups, allowing branching.

Question 20

Which of the following is TRUE regarding the difference between furanose and pyranose forms of monosaccharides?

Accepted Answer

Furanose rings contain five atoms, while pyranose rings contain six.

Carbohydrates: Structure, Function, and Diversity (Chapter 8 Study Notes)

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