$CO_2 + H_2O + \text{sunlight} \rightarrow (CH_2O)_n + O_2$

Question 1

Which of the following best explains why cellulose is a good structural material in plant cell walls?

Accepted Answer

It contains B-1,4-glycosidic linkages that create linear strands with hydrogen bonds between them.

Question 2

A scientist is studying a carbohydrate with the formula $C_6H_{12}O_6$. Which of the following statements about this molecule is most likely true?

Accepted Answer

It is a monosaccharide and could be glucose, fructose, or galactose.

Question 3

Which of the following best describes the difference between an aldose and a ketose sugar?

Accepted Answer

Aldoses have a carbonyl group at the end of the carbon chain, while ketoses have it in the middle.

Question 4

Which of the following is a function of glycoproteins on the external surface of animal cells?

Accepted Answer

Contributing to cell-cell recognition.

Question 5

A patient is unable to digest dietary fiber efficiently. Which structural feature of fiber-forming carbohydrates is most responsible for this?

Accepted Answer

B-1,4-glycosidic linkages that most digestive enzymes cannot hydrolyze.

Question 6

Which of the following best explains why glycogen is more rapidly mobilized for energy than starch?

Accepted Answer

Glycogen is highly branched, allowing more sites for enzymatic hydrolysis.

Question 7

Which of the following equations correctly represents the process of photosynthesis as it relates to carbohydrate formation?

Accepted Answer

$CO_2 + H_2O + 	ext{sunlight} ightarrow (CH_2O)_n + O_2$

Question 8

Which of the following best describes the role of carbohydrates in cell identity?

Accepted Answer

Carbohydrates attached to proteins and lipids on the cell surface serve as molecular identification tags.

Question 9

A researcher is comparing the energy content of a carbohydrate and carbon dioxide. Which statement is correct regarding their potential energy?

Accepted Answer

Carbohydrates have more C-H and C-C bonds, so they store more energy than CO_2.

Question 10

Which of the following best explains why enzymes like amylase and phosphorylase are important for animal metabolism?

Accepted Answer

They hydrolyze a-glycosidic linkages in starch and glycogen to release glucose.

Question 11

Which of the following is a correct statement about the structure of chitin?

Accepted Answer

It contains N-acetylglucosamine monomers joined by B-1,4-glycosidic linkages.

Question 12

Which of the following best describes the process by which monosaccharides are joined to form polysaccharides?

Accepted Answer

Condensation reactions between hydroxyl groups forming glycosidic linkages.

Question 13

A mutation causes a plant to produce starch with only unbranched chains. Which type of glycosidic linkage is most likely present in this starch?

Accepted Answer

a-1,4-glycosidic linkages

Question 14

Which of the following is a real-world application of glycobiology in cancer therapy?

Accepted Answer

Targeting altered glycosylated surface molecules on cancer cells with protein therapies.

Question 15

Which of the following best explains why B-1,4-glycosidic linkages are resistant to hydrolysis?

Accepted Answer

Most organisms lack enzymes that can break B-1,4-glycosidic linkages.

Question 16

Which of the following best describes the role of carbohydrates in ATP production?

Accepted Answer

Carbohydrates are broken down to glucose, which is then used to generate ATP in cellular respiration.

Question 17

Which of the following statements about peptidoglycan is correct?

Accepted Answer

It is a structural polymer in bacterial cell walls, with B-1,4-glycosidic linkages and peptide cross-links.

Question 18

Which of the following best explains why carbohydrates are considered dietary fiber and important for digestive health?

Accepted Answer

They form fibers that are resistant to digestion, promoting gut motility and health.

Chapter 5: An Introduction to Carbohydrates – Structure, Function, and Biological Roles

Study Guide - Practice Questions