Question 1

Which of the following statements best describes the difference between an atom and an ion?

Accepted Answer

An atom has an equal number of protons and electrons, while an ion has an unequal number of protons and electrons.

Question 2

Carbon-12 and Carbon-14 are both isotopes of carbon. What is the main difference between them?

Accepted Answer

Carbon-14 has more neutrons than Carbon-12.

Question 3

Which element can form the greatest number of covalent bonds according to Table 2.2?

Accepted Answer

Carbon

Question 4

A sodium atom loses one electron to become a sodium ion. What is the charge of the sodium ion?

Accepted Answer

Na$$^{+}$$

Question 5

Which of the following best explains why ionic compounds like NaCl dissolve easily in water?

Accepted Answer

Water is a polar molecule, and its charges disrupt the electrostatic attraction between Na$$^{+}$$ and Cl$$^{-}$$ ions.

Question 6

Which type of bond is responsible for holding the two strands of DNA together?

Accepted Answer

Hydrogen bonds

Question 7

What is the pH of pure water, and what does this value indicate about the concentrations of H$$^{+}$$ and OH$$^{-}$$ ions?

Accepted Answer

pH = 7; [H$$^{+}$$] = [OH$$^{-}$$]

Question 8

Which macromolecule is primarily responsible for energy storage in animals?

Accepted Answer

Glycogen

Question 9

Which of the following is a characteristic of lipids?

Accepted Answer

They are insoluble in water due to their nonpolar C-H bonds.

Question 10

Which molecule is the primary component of all cell membranes?

Accepted Answer

Phospholipids

Question 11

Which of the following best describes the structure of a nucleotide?

Accepted Answer

A sugar, a phosphate group, and a nitrogenous base

Question 12

Which of the following is NOT a function of proteins?

Accepted Answer

Energy storage

Question 13

Which of the following statements about ATP is correct?

Accepted Answer

ATP is the energy currency in all cells and is produced using glucose as fuel.

Question 14

Which of the following best explains why fungi can tolerate more acidic environments than most microbes?

Accepted Answer

Fungi have adaptations that allow their enzymes to function at lower pH values.

Question 15

Which of the following is a correct representation of a double covalent bond?

Accepted Answer

$$\mathrm{C=C}$$

Question 16

Which of the following is true about the polarity of water molecules?

Accepted Answer

Water molecules are polar because oxygen 'hogs' the electrons, creating partial charges.

Question 17

Which of the following is a polymer of glucose used for energy storage in plants?

Accepted Answer

Starch

Question 18

Which of the following best describes the relationship between pH and H$$^{+}$$ concentration?

Accepted Answer

pH is the exponent on the concentration of H$$^{+}$$ ions.

Question 19

Which of the following is a correct description of the structure of steroids?

Accepted Answer

Steroids have four fused carbon rings.

Question 20

Which of the following is a correct statement about the structure of proteins?

Accepted Answer

The unique 3D shape of a protein is determined by interactions between the R groups of amino acids.

Chemical Principles in Microbiology: Atoms, Bonds, and Biological Macromolecules

Study Guide - Practice Questions