Question 1

Which of the following best describes a hydrocarbon?

Accepted Answer

A molecule consisting only of carbon and hydrogen atoms

Question 2

Which type of isomerism is responsible for the difference between 11-cis retinal and all-trans retinal, which is crucial for vision?

Accepted Answer

Cis-trans (geometric) isomerism

Question 3

A pharmaceutical company accidentally produces the right-handed enantiomer of a drug instead of the left-handed form. What is a likely consequence?

Accepted Answer

The drug may be ineffective or cause harmful side effects because biological systems are sensitive to molecular chirality.

Question 4

Which functional group is present in all amino acids and is responsible for their acidic properties?

Accepted Answer

Carboxyl group $(-COOH)$

Question 5

Which of the following statements about dehydration synthesis is correct?

Accepted Answer

It joins monomers by removing a water molecule, forming a covalent bond.

Question 6

A patient with a rare genetic disorder cannot convert all-trans retinal back to 11-cis retinal. What symptom would you expect?

Accepted Answer

Difficulty adapting to changes in light, such as night blindness

Question 7

Which of the following best explains why glucose and fructose, both with the formula $C_6H_{12}O_6$, have different properties?

Accepted Answer

They are structural isomers with different arrangements of atoms.

Question 8

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

Accepted Answer

A covalent bond formed between two monosaccharides by a dehydration reaction

Question 9

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

Accepted Answer

They have different types of glycosidic linkages, resulting in different three-dimensional structures.

Question 10

Which of the following is NOT a function of carbohydrates in living organisms?

Accepted Answer

Catalyzing chemical reactions

Question 11

A dehydration reaction between two glucose molecules produces which disaccharide and what byproduct?

Accepted Answer

Maltose and water

Question 12

Which of the following best explains why humans can digest starch but not cellulose?

Accepted Answer

Humans have enzymes that hydrolyze the $\alpha$ glycosidic linkages in starch but not the $\beta$ linkages in cellulose.

Question 13

Which of the following is a correct statement about enantiomers?

Accepted Answer

They are isomers that are non-superimposable mirror images of each other.

Question 14

Which of the following is a real-world consequence of the different isomers of thalidomide?

Accepted Answer

One isomer is a sedative, while the other causes birth defects.

Question 15

Which of the following best describes the process of hydrolysis?

Accepted Answer

It breaks down polymers into monomers by adding a water molecule.

Question 16

Which of the following is a correct statement about the structure of glucose in aqueous solution?

Accepted Answer

It predominantly exists in a ring form.

Question 17

Which of the following best explains why high fructose corn syrup is associated with health risks?

Accepted Answer

Fructose is rapidly converted to fat in the liver and can promote bad cholesterol.

Question 18

Which of the following is a correct pairing of a biological molecule and its monomer?

Accepted Answer

Protein – amino acid

Question 19

Which of the following best describes the role of functional groups in organic molecules?

Accepted Answer

They determine the unique chemical properties and reactivity of molecules.

Question 20

A scientist is studying a new sugar with the formula $C_5H_{10}O_5$. Which class of monosaccharide does this sugar belong to?

Accepted Answer

Pentose

Carbon and Biological Molecules: Structure and Function

Study Guide - Practice Questions