Question 1

Which of the following statements best describes the difference between mass and weight?

Accepted Answer

Mass is the amount of matter a substance contains, while weight is the force of gravity acting on that mass.

Question 2

Which chemical element is most abundant in the human body by mass and is essential for generating ATP?

Accepted Answer

Oxygen (O)

Question 3

A patient is experiencing muscle cramps due to an imbalance of the most plentiful cation in intracellular fluid. Which ion is most likely involved?

Accepted Answer

K$^{+}$ (Potassium)

Question 4

Which of the following best explains why water is considered the most important inorganic compound in living organisms?

Accepted Answer

Water acts as a solvent, participates in chemical reactions, and helps regulate temperature.

Question 5

Which type of chemical bond is responsible for the surface tension of water?

Accepted Answer

Hydrogen bonds

Question 6

A solution is prepared by dissolving 58.44 g of NaCl in enough water to make 1 liter. What is the molarity of this solution?

Accepted Answer

$1\ \mathrm{M}$

Question 7

Which of the following is a correct example of a synthesis (anabolic) reaction?

Accepted Answer

$2\mathrm{H}_2 + \mathrm{O}_2 \rightarrow 2\mathrm{H}_2\mathrm{O}$

Question 8

Which property of water allows it to help regulate body temperature during exercise?

Accepted Answer

High heat of vaporization

Question 9

Which of the following best describes the role of buffer systems in the body?

Accepted Answer

Buffers maintain pH homeostasis by converting strong acids or bases into weak ones.

Question 10

Which functional group is found at the end of an amino acid and gives it acidic properties?

Accepted Answer

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

Question 11

Which of the following is a polysaccharide that serves as the main energy storage molecule in animals?

Accepted Answer

Glycogen

Question 12

A patient has a deficiency in Vitamin K. Which physiological process is most likely to be affected?

Accepted Answer

Synthesis of blood-clotting proteins

Question 13

Which type of lipid is the major component of cell membranes?

Accepted Answer

Phospholipids

Question 14

Which of the following best describes the structure of DNA?

Accepted Answer

Double helix with thymine as a base

Question 15

Which process produces the most ATP per molecule of glucose in human cells?

Accepted Answer

Aerobic respiration

Question 16

Which of the following is true about enzymes?

Accepted Answer

Enzymes are highly specific and act as catalysts in living cells.

Question 17

Which of the following reactions is an example of an oxidation-reduction (redox) reaction?

Accepted Answer

Transfer of electrons from one molecule to another, resulting in one being oxidized and the other reduced.

Question 18

Which of the following best explains why carbon is the backbone of organic molecules?

Accepted Answer

Carbon can combine in a variety of shapes and forms stable covalent bonds.

Question 19

A patient is found to have low levels of Fe$^{2+}$ in their blood. Which function is most likely impaired?

Accepted Answer

Oxygen transport by hemoglobin

Question 20

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

Accepted Answer

Organic compounds always contain carbon and hydrogen, and have covalent bonds; inorganic compounds usually lack carbon and are simple molecules.

Chapter 2: The Chemical Level of Organization – Principles of Anatomy and Physiology

Study Guide - Practice Questions