Question 1

Which enzyme is responsible for the digestion of lactose in the human small intestine, and what is the consequence of its deficiency?

Accepted Answer

Lactase; symptoms such as nausea, cramps, and bloating

Question 2

Why are carbon atoms uniquely suited to form the backbone of organic molecules?

Accepted Answer

They can form four covalent bonds, allowing for large and diverse compounds

Question 3

Which of the following best describes a hydrocarbon?

Accepted Answer

A molecule composed only of carbon and hydrogen

Question 4

What is the main reason that functional groups such as hydroxyl, carbonyl, and amino groups make organic compounds hydrophilic?

Accepted Answer

Their oxygen or nitrogen atoms exert a strong pull on shared electrons, making them polar

Question 5

Which functional group acts as an acid by donating an $$H^+$$ ion to a solution?

Accepted Answer

Carboxyl group ($$-COOH)$$

Question 6

A molecule with the formula $$C_4H_8$$ can be either 1-butene or 2-butene. What is the relationship between these two molecules?

Accepted Answer

They are isomers

Question 7

Which of the following statements about ring structures in organic chemistry is correct?

Accepted Answer

Cyclohexane and benzene are examples of hydrocarbons with ring structures

Question 8

Which functional group is present in all amino acids and acts as a base by picking up an $$H^+$$ from solution?

Accepted Answer

Amino group ($$-NH_2$)

Question 9

ATP (adenosine triphosphate) contains which functional group that is critical for energy transfer in cells?

Accepted Answer

Phosphate group

Question 10

Which of the following best explains why sexual differences in mammals have a biological basis?

Accepted Answer

The functional groups attached to the carbon skeletons of sex hormones differ, leading to different biological effects

Question 11

Which of the following is an example of a molecule with a hydroxyl group?

Accepted Answer

Ethanol ($$CH_3CH_2OH)$$

Question 12

A compound with the structure $$R-CHO is $$classified as which type of molecule?

Accepted Answer

Aldehyde

Question 13

Which of the following statements about isomers is correct?

Accepted Answer

Isomers have the same molecular formula but different structures

Question 14

Which functional group is most likely to make a molecule act as a weak acid in water?

Accepted Answer

Carboxyl group

Question 15

Which of the following best describes the role of genes in the production of enzymes such as lactase?

Accepted Answer

Genes encode the information to produce enzymes; if a gene is inactive, the enzyme is not produced

Question 16

Which of the following functional groups is found in both ATP and nucleic acids, and is essential for energy transfer?

Accepted Answer

Phosphate group

Question 17

Which of the following is a property of hydrocarbons such as cyclohexane and benzene?

Accepted Answer

They are nonpolar due to their C-H bonds

Question 18

Which of the following best explains why sugars are soluble in water?

Accepted Answer

They contain polar functional groups such as hydroxyl and carbonyl groups

Question 19

Which of the following is a correct match between a functional group and its example?

Accepted Answer

Carboxyl group — Acetic acid

Question 20

A molecule with the structure $$R-CO-CH_3$ is classified as which type of molecule?

Accepted Answer

Ketone

The Molecules of Cells: Organic Compounds and Functional Groups

Study Guide - Practice Questions