Question 1

Which of the following best explains why water is considered the 'universal solvent' in biological systems?

Accepted Answer

Because water molecules are polar, allowing them to surround and dissociate ionic and other polar substances.

Question 2

A patient is experiencing muscle cramps due to an electrolyte imbalance. Which mineral is most likely deficient, and what is its chemical symbol?

Accepted Answer

Potassium (K)

Question 3

Which of the following statements about the pH scale is correct?

Accepted Answer

A solution with pH 3 is 100 times more acidic than a solution with pH 5.

Question 4

Which of the following best describes the difference between a molecule and a compound?

Accepted Answer

A molecule is a combination of two or more atoms; a compound is a molecule composed of different kinds of atoms.

Question 5

A solution is made by dissolving 10 grams of glucose in 100 mL of water. In this solution, which is the solvent and which is the solute?

Accepted Answer

Water is the solvent; glucose is the solute.

Question 6

Which of the following best explains why enzymes are essential for life?

Accepted Answer

Enzymes lower the activation energy of biochemical reactions, allowing them to proceed at a rate compatible with life.

Question 7

Which of the following is an example of a polar covalent bond?

Accepted Answer

The bond between oxygen and hydrogen in $$\mathrm{H}_2\mathrm{O}$$

Question 8

A patient’s blood pH drops to 7.1. Which of the following best describes the role of buffers in this situation?

Accepted Answer

Buffers will bind hydrogen ions to help raise the pH back toward normal.

Question 9

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

Accepted Answer

A glycerol backbone with three attached fatty acid chains

Question 10

Which of the following is a correct example of an exchange reaction?

Accepted Answer

$$\mathrm{AB} + \mathrm{CD} \rightarrow \mathrm{AD} + \mathrm{CB}$$

Question 11

Which of the following best explains why hydrogen bonds are important in biological molecules?

Accepted Answer

They stabilize the three-dimensional structure of large molecules like proteins and DNA.

Question 12

Which of the following statements about ATP is correct?

Accepted Answer

ATP is a nucleotide that serves as the energy carrier molecule in the cell.

Question 13

A solution has a pH of 2. Which of the following statements is true about this solution?

Accepted Answer

It is a strong acid and has a high concentration of hydrogen ions ($$\mathrm{H}^+).$$

Question 14

Which of the following best describes the difference between kinetic and potential energy in the human body?

Accepted Answer

Kinetic energy is energy in action, such as muscle contraction; potential energy is stored energy, such as in ATP.

Question 15

Which of the following is a trace element essential for the function of thyroid hormones?

Accepted Answer

Iodine (I)

Question 16

Which of the following best describes the role of phospholipids in the body?

Accepted Answer

They form the primary structure of cellular membranes.

Question 17

A protein loses its three-dimensional shape due to high fever. Which property of proteins is most directly affected?

Accepted Answer

Its ability to act as a catalyst for biochemical reactions.

Question 18

Which of the following best describes the composition of a nucleotide found in DNA?

Accepted Answer

A phosphate group, a sugar, and a nitrogen-containing base

Question 19

Which of the following is an example of a decomposition (catabolic) reaction?

Accepted Answer

$$\mathrm{AB} \rightarrow \mathrm{A} + \mathrm{B}$$

Question 20

Which of the following best explains why sodium chloride ($$\mathrm{NaCl}) $$forms an ionic bond?

Accepted Answer

Sodium transfers an electron to chlorine, resulting in oppositely charged ions that attract each other.

Chapter 2: Chemistry Comes Alive – Structured Study Notes

Study Guide - Practice Questions