$$[H^+] = 1 \times 10$$^{-4}$$ \ \mathrm{M}$$

Question 1

Which of the following statements best describes an isotope?

Accepted Answer

An atom with the same number of protons but a different number of neutrons.

Question 2

A solution has a pH of 4. What is the concentration of hydrogen ions $$[H^+] in $$this solution?

Accepted Answer

$$[H^+] = 1 	imes 10$$^{-4}$$ \ \mathrm{M}$$

Question 3

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

Accepted Answer

Carboxyl group ($$\mathrm{R-COOH})$$

Question 4

Which of the following best explains why water is a good solvent for ionic compounds like NaCl?

Accepted Answer

Water molecules are polar and can stabilize both cations and anions through hydrogen bonding.

Question 5

Which of the following is a correct molecular formula for a disaccharide formed from two glucose molecules by dehydration synthesis?

Accepted Answer

$$\mathrm{C$$_{12}$$H_{22}O$$_{11}}$

Question 6

A patient’s blood pH drops to 7.1. Which of the following best describes this condition?

Accepted Answer

The patient is experiencing acidosis.

Question 7

Which type of chemical bond is primarily responsible for the secondary structure of proteins (e.g., alpha-helices and beta-sheets)?

Accepted Answer

Hydrogen bonds

Question 8

Which of the following best describes an amphipathic molecule?

Accepted Answer

A molecule that contains both hydrophobic and hydrophilic regions.

Question 9

Which of the following reactions is an example of a decomposition reaction?

Accepted Answer

$$\mathrm{C$$_{12}$$H_{22}O$$_{11} + H_2O \rightarrow C_6H_{12}$$O_6 + C_6H$$_{12}$$O_6$$}$

Question 10

Which of the following statements about buffers is correct?

Accepted Answer

Buffers stabilize pH by absorbing or releasing $$\mathrm{H^+}$$ ions.

Question 11

Which of the following best describes the difference between a cation and an anion?

Accepted Answer

A cation has lost electrons and an anion has gained electrons.

Question 12

Which of the following is a property of saturated fatty acids?

Accepted Answer

They are usually solid at room temperature.

Question 13

Which of the following bonds connects nucleotides in a DNA or RNA strand?

Accepted Answer

Phosphodiester bonds

Question 14

Which of the following best describes an exergonic reaction?

Accepted Answer

A reaction in which products have lower energy than reactants and energy is released.

Question 15

Which of the following is a real-life example of a molecule with a glycosidic bond?

Accepted Answer

Sucrose

Question 16

Which of the following best explains why mutations in DNA can affect protein function?

Accepted Answer

Mutations change the primary structure of proteins, which can alter higher-order structures and function.

Question 17

Which of the following is a correct description of a peptide bond?

Accepted Answer

A covalent bond between the amine group of one amino acid and the carboxyl group of another.

Question 18

Which of the following best describes the role of ATP in cells?

Accepted Answer

ATP serves as the main energy currency, releasing energy when phosphate groups are cleaved.

Question 19

Which of the following is true about the pH scale?

Accepted Answer

A solution with pH 3 is ten times more acidic than a solution with pH 4.

Biochemistry Basics for Microbiology: Atoms, Molecules, and Macromolecules

Study Guide - Practice Questions