2026-2027 WGU C190 Introduction to Biology - Practice
Questions | Complete Objective Assessment (OA) Review
Test Bank with Verified Answers
Pass your Western Governors University Objective Assessment
on your first attempt with this comprehensive C190 Introduction to
Biology test bank featuring practice questions. This targeted
preparation guide provides verified correct answers and clear
explanations covering cell structure, DNA replication, genetics,
evolution, and ecosystem dynamics. It is the ultimate resource for
WGU students looking to master essential life science concepts
quickly and secure a passing grade.
Question 1: Which of the following represents a population?
A) All the organisms living in a lake
B) All the fish in a pond
C) All the bass in a lake
D) The bass and the water lilies in a lake
Answer: C) All the bass in a lake
Rationale: A population consists of all individuals of a single species living in
a specific area. "All the bass in a lake" represents a single species (bass) in a
defined area. Option A includes multiple species (community), option B
includes multiple species of fish (community), and option D includes different
species (community).
Question 2: A group of organisms of different species living together
in the same area is called a:
,A) Population
B) Community
C) Ecosystem
D) Biome
Answer: B) Community
Rationale: A community is an assemblage of populations of different species
living in the same area and interacting with each other. A population is a
single species, an ecosystem includes abiotic factors, and a biome is a large-
scale community type defined by climate and vegetation.
Question 3: The subatomic particle with no charge is the:
A) Proton
B) Electron
C) Neutron
D) Ion
Answer: C) Neutron
Rationale: Neutrons are neutral subatomic particles (charge = 0) found in the
nucleus of atoms. Protons have a positive charge (+1), electrons have a
negative charge (-1), and ions are charged atoms that have gained or lost
electrons.
Question 4: What determines the atomic number of an atom?
A) Number of neutrons
B) Number of protons
C) Number of electrons
D) Total number of protons and neutrons
,Answer: B) Number of protons
Rationale: The atomic number is defined as the number of protons in the
nucleus of an atom. It is unique for each element and determines the
element's identity. The number of neutrons determines the isotope, and the
mass number is the sum of protons and neutrons.
Question 5: Which type of bond is formed when electrons are
completely transferred from one atom to another?
A) Covalent bond
B) Ionic bond
C) Hydrogen bond
D) Metallic bond
Answer: B) Ionic bond
Rationale: An ionic bond forms when one atom completely transfers one or
more electrons to another atom, creating oppositely charged ions that attract
each other. Covalent bonds involve sharing electrons, hydrogen bonds are
weak intermolecular attractions, and metallic bonds occur between metal
atoms.
Question 6: When salt (NaCl) dissolves in water, what happens to the
ionic bonds?
A) They become stronger
B) They are broken by the water molecules
C) They form covalent bonds
D) They remain unchanged
Answer: B) They are broken by the water molecules
, Rationale: When salt dissolves in water, the polar water molecules interact
with the Na⁺ and Cl⁻ ions. The partial negative oxygen of water surrounds
Na⁺ ions, and the partial positive hydrogen surrounds Cl⁻ ions, breaking the
ionic bonds. This is why water is called the "universal solvent."
Question 7: A solution with a pH of 10 has how many times more
hydroxide ions (OH⁻) than a solution with a pH of 7?
A) 3 times
B) 10 times
C) 100 times
D) 1000 times
Answer: D) 1000 times
Rationale: The pH scale is logarithmic; each unit increase in pH represents a
10-fold decrease in H⁺ concentration and a 10-fold increase in OH⁻
concentration. A pH increase from 7 to 10 is a change of 3 units, so the OH⁻
concentration is 10 × 10 × 10 = 1000 times higher.
Question 8: Which carbohydrate is the primary storage form of energy
in animals?
A) Starch
B) Cellulose
C) Glycogen
D) Chitin
Answer: C) Glycogen
Rationale: Glycogen is the primary storage form of glucose in animals and is
stored primarily in the liver and muscles. Starch is the storage form in plants,
Questions | Complete Objective Assessment (OA) Review
Test Bank with Verified Answers
Pass your Western Governors University Objective Assessment
on your first attempt with this comprehensive C190 Introduction to
Biology test bank featuring practice questions. This targeted
preparation guide provides verified correct answers and clear
explanations covering cell structure, DNA replication, genetics,
evolution, and ecosystem dynamics. It is the ultimate resource for
WGU students looking to master essential life science concepts
quickly and secure a passing grade.
Question 1: Which of the following represents a population?
A) All the organisms living in a lake
B) All the fish in a pond
C) All the bass in a lake
D) The bass and the water lilies in a lake
Answer: C) All the bass in a lake
Rationale: A population consists of all individuals of a single species living in
a specific area. "All the bass in a lake" represents a single species (bass) in a
defined area. Option A includes multiple species (community), option B
includes multiple species of fish (community), and option D includes different
species (community).
Question 2: A group of organisms of different species living together
in the same area is called a:
,A) Population
B) Community
C) Ecosystem
D) Biome
Answer: B) Community
Rationale: A community is an assemblage of populations of different species
living in the same area and interacting with each other. A population is a
single species, an ecosystem includes abiotic factors, and a biome is a large-
scale community type defined by climate and vegetation.
Question 3: The subatomic particle with no charge is the:
A) Proton
B) Electron
C) Neutron
D) Ion
Answer: C) Neutron
Rationale: Neutrons are neutral subatomic particles (charge = 0) found in the
nucleus of atoms. Protons have a positive charge (+1), electrons have a
negative charge (-1), and ions are charged atoms that have gained or lost
electrons.
Question 4: What determines the atomic number of an atom?
A) Number of neutrons
B) Number of protons
C) Number of electrons
D) Total number of protons and neutrons
,Answer: B) Number of protons
Rationale: The atomic number is defined as the number of protons in the
nucleus of an atom. It is unique for each element and determines the
element's identity. The number of neutrons determines the isotope, and the
mass number is the sum of protons and neutrons.
Question 5: Which type of bond is formed when electrons are
completely transferred from one atom to another?
A) Covalent bond
B) Ionic bond
C) Hydrogen bond
D) Metallic bond
Answer: B) Ionic bond
Rationale: An ionic bond forms when one atom completely transfers one or
more electrons to another atom, creating oppositely charged ions that attract
each other. Covalent bonds involve sharing electrons, hydrogen bonds are
weak intermolecular attractions, and metallic bonds occur between metal
atoms.
Question 6: When salt (NaCl) dissolves in water, what happens to the
ionic bonds?
A) They become stronger
B) They are broken by the water molecules
C) They form covalent bonds
D) They remain unchanged
Answer: B) They are broken by the water molecules
, Rationale: When salt dissolves in water, the polar water molecules interact
with the Na⁺ and Cl⁻ ions. The partial negative oxygen of water surrounds
Na⁺ ions, and the partial positive hydrogen surrounds Cl⁻ ions, breaking the
ionic bonds. This is why water is called the "universal solvent."
Question 7: A solution with a pH of 10 has how many times more
hydroxide ions (OH⁻) than a solution with a pH of 7?
A) 3 times
B) 10 times
C) 100 times
D) 1000 times
Answer: D) 1000 times
Rationale: The pH scale is logarithmic; each unit increase in pH represents a
10-fold decrease in H⁺ concentration and a 10-fold increase in OH⁻
concentration. A pH increase from 7 to 10 is a change of 3 units, so the OH⁻
concentration is 10 × 10 × 10 = 1000 times higher.
Question 8: Which carbohydrate is the primary storage form of energy
in animals?
A) Starch
B) Cellulose
C) Glycogen
D) Chitin
Answer: C) Glycogen
Rationale: Glycogen is the primary storage form of glucose in animals and is
stored primarily in the liver and muscles. Starch is the storage form in plants,
