Question 1

Which of the following statements best explains why glucose is classified as a reducing sugar?

Accepted Answer

Because it contains a free aldehyde group in its open-chain form that can react with oxidizing agents.

Question 2

Which type of glycosidic bond is found at the branch points of glycogen?

Accepted Answer

$$\alpha-1$$,6-glycosidic bond

Question 3

A patient with diabetes has elevated levels of hemoglobin A1c. This is due to which biochemical process?

Accepted Answer

Non-enzymatic glycation of hemoglobin by glucose

Question 4

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

Accepted Answer

Amylose has $$\alpha-1$$,4-glycosidic bonds, while cellulose has $$\beta-1$$,4-glycosidic bonds.

Question 5

Which of the following modifications to a monosaccharide would most likely prevent it from leaving the cell and facilitate its metabolism?

Accepted Answer

Phosphorylation

Question 6

Which enzyme is responsible for catalyzing the formation of glycosidic bonds during oligosaccharide assembly?

Accepted Answer

Glycosyltransferase

Question 7

A disaccharide is composed of two monosaccharides joined by which type of bond?

Accepted Answer

O-glycosidic bond

Question 8

Which of the following best explains why cellulose is a good structural material in plants?

Accepted Answer

Its $$\beta-1$$,4-glycosidic linkages allow for straight chains that form strong fibrils via hydrogen bonding.

Question 9

Which of the following is a correct statement about glycoproteins?

Accepted Answer

They are proteins covalently attached to carbohydrates, often functioning as membrane proteins.

Question 10

Which of the following best describes the role of lectins in biological systems?

Accepted Answer

They are proteins that bind specific carbohydrate structures to mediate cell-cell interactions.

Question 11

Which of the following statements about sucrose is correct?

Accepted Answer

It is a disaccharide composed of glucose and fructose linked by an $$\alpha-1$$,2-glycosidic bond.

Question 12

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

Accepted Answer

Humans lack enzymes that can hydrolyze $$\beta-1$$,4-glycosidic bonds.

Question 13

Which of the following is a correct pairing of a glycoprotein linkage and the amino acid involved?

Accepted Answer

N-linked glycosidic bond to asparagine

Question 14

A scientist is studying a polysaccharide that is highly branched and serves as a glucose storage form in animals. Which polysaccharide is she most likely studying?

Accepted Answer

Glycogen

Question 15

Which of the following best describes the function of proteoglycans in cartilage?

Accepted Answer

They provide cushioning by releasing and rebinding water upon impact.

Question 16

Which of the following is a correct statement about the formation of cyclic forms of monosaccharides?

Accepted Answer

A hemiacetal is formed when an aldehyde reacts with an alcohol within the same molecule.

Question 17

Which of the following best explains the significance of advanced glycation end products (AGEs) in human health?

Accepted Answer

AGEs are formed by non-enzymatic reactions between carbohydrates and proteins and are implicated in pathological conditions.

Question 18

Which of the following best describes the role of sialic acid residues in viral infection?

Accepted Answer

They serve as binding sites for influenza virus on cell-surface glycoproteins.

Question 19

Which of the following statements about chitin is correct?

Accepted Answer

Chitin is a glycosaminoglycan found in the exoskeletons of insects, crustaceans, and arachnids.

Question 20

A patient is unable to digest lactose. Which enzyme is most likely deficient, and what is the glycosidic linkage in lactose?

Accepted Answer

Lactase; $$\beta-1$$,4-glycosidic bond

Chapter 11: Carbohydrates – Structure, Isomerism, and Biological Roles

Guida di studio - Domande di pratica

Study guide - Flashcard