Question 1

Which of the following statements best describes a chiral molecule?

Accepted Answer

A molecule that cannot be superimposed on its mirror image due to the presence of at least one carbon atom bonded to four different groups.

Question 2

Which of the following objects is achiral based on the images provided?

Accepted Answer

A drinking glass

Question 3

How many stereoisomers are possible for a molecule with three chiral centers?

Accepted Answer

$$2^3 = 8$

Question 4

Which of the following best describes an enantiomer?

Accepted Answer

A pair of molecules that are non-superimposable mirror images of each other.

Question 5

Which of the following is true about D- and L-glyceraldehyde?

Accepted Answer

They are enantiomers and differ in the direction they rotate plane-polarized light.

Question 6

Which of the following best describes the difference between an α-anomer and a β-anomer of glucose?

Accepted Answer

The α-anomer has the OH group on the anomeric carbon on the opposite side from the CH$$_2OH $$group, while the β-anomer has it on the same side.

Question 7

Which of the following sugars is a reducing sugar?

Accepted Answer

Maltose

Question 8

Which of the following best explains why humans cannot digest cellulose?

Accepted Answer

Cellulose contains β(1→4) glycosidic bonds, and humans lack the enzyme to hydrolyze these bonds.

Question 9

Which of the following is an epimer of D-glucose at carbon 2?

Accepted Answer

D-Mannose

Question 10

What is the product when D-glucose is oxidized at its aldehyde group?

Accepted Answer

D-Gluconic acid

Question 11

Which of the following best describes mutarotation?

Accepted Answer

The conversion between α and β anomers of a sugar via the open-chain form.

Question 12

Which of the following is a correct description of a Haworth projection?

Accepted Answer

A two-dimensional representation of a sugar ring with the plane of the ring perpendicular to the page.

Question 13

Which of the following best describes the glycosidic bond in sucrose?

Accepted Answer

An α(1→2)β bond between glucose and fructose.

Question 14

Which of the following is a function of polysaccharide branching in glycogen?

Accepted Answer

It provides multiple non-reducing ends for rapid enzymatic breakdown.

Question 15

Which of the following statements about enantiomers is correct?

Accepted Answer

They have identical physical properties except for their interaction with plane-polarized light and other chiral molecules.

Question 16

Which of the following is true about the digestion of disaccharides in humans?

Accepted Answer

Humans can digest lactose because they produce β-D-galactosidase (lactase), but not cellobiose.

Question 17

Which of the following best describes the difference between amylose and cellulose?

Accepted Answer

Amylose is a polymer of glucose with α(1→4) linkages, while cellulose is a polymer of glucose with β(1→4) linkages.

Question 18

Which of the following is a ketopentose?

Accepted Answer

D-Ribulose

Question 19

Which of the following best explains why D-sugars are more common in nature than L-sugars?

Accepted Answer

Enzymes in biological systems are stereospecific and typically recognize D-sugars.

Carbohydrates and Stereochemistry: Structure, Function, and Isomerism

Study Guide - Practice Questions