Question 1

Which functional group is most likely to increase the solubility of a molecule in water due to its polarity?

Accepted Answer

Amino group ($$-NH_2$)

Question 2

A molecule contains both a carboxyl group and an amino group. At physiological pH (around 7.4), what is the likely charge of this molecule?

Accepted Answer

It will have both a positive and a negative charge (zwitterion).

Question 3

Which of the following best explains why the methyl group ($$-CH_3$) is classified as nonpolar?

Accepted Answer

It consists of atoms with similar electronegativities, resulting in equal sharing of electrons.

Question 4

Which functional group is responsible for making a molecule act as a base by accepting a hydrogen ion ($$H^+) $$from solution?

Accepted Answer

Amino group ($$-NH_2$)

Question 5

A scientist is studying a molecule that contains a phosphate group. Which property is most likely associated with this molecule?

Accepted Answer

It is charged and acidic.

Question 6

Which of the following functional groups is most likely to participate in hydrogen bonding with water molecules?

Accepted Answer

Hydroxyl group ($$-OH)$$

Question 7

A molecule with a carboxyl group ($$-COOH) is $$added to water. What is the most likely result?

Accepted Answer

The carboxyl group will donate a proton to water, becoming negatively charged.

Question 8

Which functional group is found in ATP and is critical for energy transfer in cells?

Accepted Answer

Phosphate group ($$-PO_4$^{2-})$$

Question 9

A mutation causes a serine residue (which contains a hydroxyl group) in a protein to be replaced by alanine (which contains a methyl group). What is the most likely effect on the protein's properties?

Accepted Answer

The protein will lose the ability to form hydrogen bonds at that site.

Question 10

Which of the following best describes the difference between polar and nonpolar functional groups?

Accepted Answer

Polar groups have uneven sharing of electrons, leading to partial charges, while nonpolar groups have even sharing of electrons.

Question 11

A researcher adds a molecule with a sulfhydryl group ($$-SH) to a $$solution containing another molecule with a sulfhydryl group. What type of bond might form between these two molecules?

Accepted Answer

Disulfide bond

Question 12

Which functional group is most likely to be found in fatty acids and is responsible for their acidic properties?

Accepted Answer

Carboxyl group ($$-COOH)$$

Question 13

A molecule contains both a phosphate group and a methyl group. Which statement best describes its likely properties?

Accepted Answer

It is likely to be charged and acidic due to the phosphate group.

Question 14

Which of the following functional groups is most likely to be found in nucleic acids and is essential for their backbone structure?

Accepted Answer

Phosphate group ($$-PO_4$^{2-})$$

Question 15

A solution contains a molecule with an amino group. If the pH of the solution decreases, what is the most likely effect on the amino group?

Accepted Answer

It will gain a proton and become positively charged.

Question 16

Which functional group is most likely to be involved in the formation of peptide bonds between amino acids?

Accepted Answer

Both carboxyl ($$-COOH) $$and amino ($$-NH_2$) groups

Question 17

A molecule with a hydroxyl group is added to water. Which of the following best describes its interaction with water?

Accepted Answer

It will form hydrogen bonds with water, increasing solubility.

Question 18

Which of the following best explains why carboxyl groups are acidic?

Accepted Answer

They can donate a proton to solution, leaving behind a negatively charged ion.

Question 19

A molecule contains a sulfhydryl group ($$-SH). $$Which of the following is a likely function of this group in proteins?

Accepted Answer

It forms disulfide bridges that stabilize protein structure.

Question 20

Which of the following functional groups is most likely to be found in alcohols and is responsible for their polar nature?

Accepted Answer

Hydroxyl group ($$-OH)$$

UNIT 1: Functional Groups and Their Properties in Biology

Study Guide - Practice Questions

Study Guide - Flashcards