$$[H^+] = 1 \times 10$$^{-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 of the following best explains why water is a good solvent for polar substances?

Accepted Answer

Water molecules form hydrogen bonds with polar molecules due to their polar covalent bonds.

Question 4

Which of the following is true regarding the formation of a cation?

Accepted Answer

A cation is formed when an atom loses electrons.

Question 5

Which of the following molecules is amphipathic and plays a key role in forming cellular membranes?

Accepted Answer

Phospholipid

Question 6

A protein's tertiary structure is primarily stabilized by which of the following interactions?

Accepted Answer

Hydrogen bonds, ionic bonds, van der Waals interactions, and disulfide bridges

Question 7

Which of the following best describes the difference between organic and inorganic molecules?

Accepted Answer

Organic molecules contain both carbon and hydrogen; inorganic molecules may contain carbon but lack associated hydrogen.

Question 8

Which of the following bonds is responsible for connecting nucleotides in a DNA strand?

Accepted Answer

Phosphodiester bond

Question 9

A solution changes from pH 7 to pH 5. How does the hydrogen ion concentration change?

Accepted Answer

It increases by 100-fold.

Question 10

Which of the following is a function of carbohydrates in cells?

Accepted Answer

Energy storage, structural support, and cellular communication

Question 11

Which of the following best describes a peptide bond?

Accepted Answer

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

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 best explains why buffers are important in biological systems?

Accepted Answer

They stabilize pH by absorbing or releasing hydrogen ions.

Question 14

Which of the following is true about the primary structure of a protein?

Accepted Answer

It is the sequence of amino acids in a polypeptide chain.

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 describes the role of ATP in cells?

Accepted Answer

It serves as the main energy currency by releasing energy when phosphate groups are cleaved.

Question 17

Which of the following is a characteristic of hydrogen bonds?

Accepted Answer

They are noncovalent attractions between a hydrogen atom and an electronegative atom.

Question 18

Which of the following best describes the difference between DNA and RNA?

Accepted Answer

DNA is double-stranded and contains deoxyribose; RNA is single-stranded and contains ribose.

Question 19

Which of the following is a function of cholesterol in animal cells?

Accepted Answer

It is incorporated into plasma membranes to modulate fluidity.

Question 20

A patient’s arterial blood pH is measured at 7.25. Which condition does this indicate?

Accepted Answer

Acidosis

Biochemistry Basics for Microbiology Students

Study Guide - Practice Questions