Question 1

Which of the following best describes a chemical element, and which four elements make up the majority of the human body by mass?

Accepted Answer

A chemical element is a substance that cannot be broken down into simpler substances by ordinary chemical means; the four elements are carbon, hydrogen, oxygen, and nitrogen.

Question 2

Which subatomic particle is responsible for the chemical behavior of atoms, and where is it located?

Accepted Answer

The electron, which has a negligible mass, a negative charge, and is located in orbitals surrounding the nucleus.

Question 3

Given an atom with 11 protons, 12 neutrons, and 11 electrons, what is its atomic number and atomic mass?

Accepted Answer

Atomic number: 11; Atomic mass: 23

Question 4

Which of the following best distinguishes a compound from a mixture?

Accepted Answer

A compound has atoms chemically bonded in fixed ratios, while a mixture contains substances physically combined in variable proportions.

Question 5

Which of the following best describes a colloid?

Accepted Answer

A mixture with particles larger than those in a solution but small enough to remain suspended and not settle out.

Question 6

According to the octet rule, how do atoms achieve chemical stability?

Accepted Answer

By gaining, losing, or sharing electrons to have eight electrons in their valence shell.

Question 7

Which of the following is an example of an ionic bond?

Accepted Answer

The transfer of an electron from sodium to chlorine to form NaCl.

Question 8

Which statement correctly compares polar and nonpolar covalent bonds?

Accepted Answer

Polar covalent bonds involve unequal sharing of electrons, resulting in partial charges; nonpolar covalent bonds involve equal sharing of electrons.

Question 9

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

Accepted Answer

$$ AB \rightarrow A + B $$

Question 10

Why are many chemical reactions in the human body considered irreversible?

Accepted Answer

Because products are often removed from the reaction site or used in other reactions, preventing the reverse reaction.

Question 11

Which factor would increase the rate of a chemical reaction in the body?

Accepted Answer

Increasing the temperature, which raises kinetic energy and collision frequency.

Question 12

What is the primary role of water in maintaining body homeostasis?

Accepted Answer

It acts as a universal solvent, facilitating chemical reactions and transport of substances.

Question 13

Which of the following best defines an acid and its effect on pH?

Accepted Answer

An acid is a substance that releases $$ H^+ $$ ions in solution, lowering the pH.

Question 14

Which process is responsible for joining two monosaccharides to form a disaccharide, and what is released during this reaction?

Accepted Answer

Dehydration synthesis; water ($$ H_2O ) is $$released.

Question 15

Which of the following correctly matches a macromolecule with its monomer and primary function?

Accepted Answer

Protein – amino acid – catalyzes biochemical reactions.

Question 16

Which level of protein structure is defined by the sequence of amino acids in a polypeptide chain?

Accepted Answer

Primary structure

Question 17

How do enzymes speed up chemical reactions in the body?

Accepted Answer

By lowering the activation energy required for the reaction to proceed.

Question 18

Which of the following statements best contrasts DNA and RNA?

Accepted Answer

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

Question 19

A patient is given a solution with a pH of 4. How does this solution compare to a solution with a pH of 7 in terms of hydrogen ion concentration?

Accepted Answer

It has 1,000 times more $$ H^+ $$ ions than the solution with pH 7.

Question 20

Which of the following best describes an oxidation-reduction (redox) reaction in the body?

Accepted Answer

A reaction in which one molecule loses electrons (is oxidized) and another gains electrons (is reduced).

Chapter 2: Basic Chemistry for Anatomy & Physiology

Study Guide - Practice Questions

Study Guide - Flashcards