Campbell Biology AP® Edition 11th Edition
Comprehensive Practice Exam 2026/2027
TABLE OF CONTENTS
Section Topic Area Questions
I Evolution, Themes of Biology & Scientific Inquiry 1–10
II The Chemical Context of Life 11–18
III Water and Life 19–24
IV Carbon & Molecular Diversity of Life 25–30
V Structure & Function of Large Biological Molecules 31–40
VI A Tour of the Cell 41–50
VII Membrane Structure and Function 51–58
VIII An Introduction to Metabolism 59–66
IX Cellular Respiration and Fermentation 67–76
X Photosynthesis 77–84
XI Cell Communication 85–90
XII The Cell Cycle 91–96
XIII Meiosis and Sexual Life Cycles 97–102
XIV Mendel and the Gene Idea 103–110
XV The Molecular Basis of Inheritance 111–118
XVI Gene Expression: From Gene to Protein 119–126
XVII Regulation of Gene Expression 127–130
SECTION I: EVOLUTION, THEMES OF BIOLOGY & SCIENTIFIC INQUIRY
,Questions 1–10
1. A researcher is studying a population of bacteria that has been exposed to a new antibiotic. Over several generations, the
bacteria become increasingly resistant. Which of the following best describes the mechanism driving this change?
A) Acquired characteristics inherited from the parent generation
B) Natural selection acting on existing genetic variation
C) Directed mutation in response to the antibiotic
D) Genetic drift reducing diversity in the population
E) Gene flow introducing resistance genes from other species
🔵 B — Natural selection acts on heritable variation present in the population. Bacteria with resistance-conferring
mutations survive and reproduce, passing these traits to offspring. Antibiotic exposure does not cause mutations; it selects
for pre-existing resistant variants. Acquired characteristics are not inherited (Lamarckian inheritance is rejected). Directed
mutation is not supported by evidence. Genetic drift is random and would not consistently produce resistance.
2. Which of the following is NOT a unifying theme of biology as described in the Campbell Biology AP Edition?
A) Evolution accounts for the unity and diversity of life
B) Living organisms use energy and matter to maintain organization
C) All biological systems are closed systems that do not exchange matter with their surroundings
D) Structure and function are correlated at all levels of biological organization
E) Feedback mechanisms regulate biological systems
🔵 C — Living systems are open systems that exchange energy and matter with their surroundings. Evolution, energy
processing, structure-function correlation, and regulation are all core themes of biology. The statement that biological
systems are closed is incorrect—organisms constantly take in energy and matter and release waste products.
3. Cells are the fundamental units of life. Which statement accurately distinguishes prokaryotic and eukaryotic cells?
A) Prokaryotic cells contain membrane-bound organelles, while eukaryotic cells do not
B) Eukaryotic cells have a nucleus; prokaryotic cells lack a true nucleus
C) Prokaryotic cells are always larger than eukaryotic cells
D) Eukaryotic cells lack ribosomes, while prokaryotic cells contain them
E) Prokaryotic cells contain linear DNA; eukaryotic cells contain circular DNA
🔵 B — The presence of a membrane-enclosed nucleus is the defining characteristic that distinguishes eukaryotic from
prokaryotic cells. Prokaryotic cells lack membrane-bound organelles, have circular DNA, and contain ribosomes (70S).
Eukaryotic cells have membrane-bound organelles (including the nucleus), linear DNA, and ribosomes (80S). Prokaryotic
cells are generally smaller than eukaryotic cells.
4. A scientist designs an experiment to test whether a new fertilizer increases plant growth. She divides 100 plants into two
groups: 50 receive the fertilizer, and 50 receive water only. All other conditions (light, temperature, soil type) are identical.
What is the independent variable in this experiment?
A) Plant growth rate
B) The amount of water given
C) The presence or absence of fertilizer
,D) The type of soil used
E) The temperature of the growth chamber
🔵 C — The independent variable is the factor that the researcher manipulates—in this case, the presence or absence of
fertilizer. Plant growth rate is the dependent variable (what is measured). Water, soil, and temperature are controlled
variables that must be kept constant.
5. A controlled experiment is one that:
A) Proceeds slowly enough that a scientist can make careful records
B) Tests experimental and control groups in parallel
C) Is repeated many times to ensure accuracy
D) Includes at least two groups, one differing from the other by a single variable
E) Both B and D
🔵 E — A controlled experiment compares an experimental group with a control group that differs by only one variable.
This allows the researcher to attribute any differences in outcome to the manipulated variable. Multiple repetitions
(replication) increase confidence in results but are not the defining feature of a controlled experiment.
6. Which level of biological organization is the simplest level that exhibits all characteristics of life?
A) Organelle
B) Cell
C) Tissue
D) Organ
E) Organism
🔵 B — The cell is the smallest unit of life that can perform all necessary functions of living organisms. Cells are the basic
structural and functional units of life. Organelles are not independently living; tissues, organs, and organisms are composed
of cells and represent higher levels of organization.
7. The process by which information in a gene directs the synthesis of a protein is called:
A) Replication
B) Transcription
C) Translation
D) Gene expression
E) Post-translational modification
🔵 D — Gene expression is the overall process by which genetic information flows from gene to protein. It encompasses
both transcription (DNA → mRNA) and translation (mRNA → protein). Replication is DNA copying. Post-translational
modification occurs after protein synthesis.
8. A biologist discovers a new organism that is unicellular, lacks a nucleus, and has a cell wall composed of peptidoglycan.
This organism most likely belongs to which domain?
A) Eukarya
B) Bacteria
C) Archaea
, D) Protista
E) Fungi
🔵 B — The presence of peptidoglycan in the cell wall is a characteristic feature of Bacteria. Archaea have cell walls but lack
peptidoglycan. Eukarya have a nucleus and membrane-bound organelles. Protista and Fungi are eukaryotic kingdoms.
9. Which of the following best describes the relationship between structure and function in biology?
A) Structure and function are unrelated; organisms can have any structure regardless of function
B) Function determines structure; organisms evolve structures based on what they need
C) Structure determines function; the physical form of a biological structure enables its specific function
D) Structure is fixed by genetics and never changes regardless of environmental conditions
E) Function is always more important than structure in determining evolutionary fitness
🔵 C — The correlation between structure and function is a fundamental theme in biology. The specific shape and
composition of a biological structure enable it to perform its function (e.g., the shape of enzymes allows them to bind
specific substrates; the structure of lungs maximizes gas exchange surface area).
10. Which of the following is an example of negative feedback in a biological system?
A) The release of oxytocin during childbirth, which stimulates stronger contractions
B) Blood glucose levels rising after a meal, triggering insulin release, which lowers blood glucose
C) A platelet releasing chemicals that attract more platelets to a wound site
D) An action potential triggering the opening of more sodium channels
E) Fruit ripening releasing ethylene, which stimulates more ripening
🔵 B — Negative feedback counteracts a change to maintain homeostasis. When blood glucose rises, insulin is released to
lower it, returning the system to its set point. All other options describe positive feedback, where a response amplifies the
initial stimulus.
SECTION II: THE CHEMICAL CONTEXT OF LIFE
Questions 11–18
11. The four most abundant elements in living organisms are:
A) Carbon, hydrogen, oxygen, and nitrogen
B) Carbon, hydrogen, oxygen, and phosphorus
C) Carbon, nitrogen, oxygen, and sulfur
D) Hydrogen, oxygen, nitrogen, and calcium
E) Carbon, oxygen, nitrogen, and potassium
🔵 A — Carbon, hydrogen, oxygen, and nitrogen make up approximately 96% of living matter. These elements are
essential for forming organic molecules. Phosphorus and sulfur are also important but are present in smaller amounts
(about 1% and 0.2-1%, respectively).
Comprehensive Practice Exam 2026/2027
TABLE OF CONTENTS
Section Topic Area Questions
I Evolution, Themes of Biology & Scientific Inquiry 1–10
II The Chemical Context of Life 11–18
III Water and Life 19–24
IV Carbon & Molecular Diversity of Life 25–30
V Structure & Function of Large Biological Molecules 31–40
VI A Tour of the Cell 41–50
VII Membrane Structure and Function 51–58
VIII An Introduction to Metabolism 59–66
IX Cellular Respiration and Fermentation 67–76
X Photosynthesis 77–84
XI Cell Communication 85–90
XII The Cell Cycle 91–96
XIII Meiosis and Sexual Life Cycles 97–102
XIV Mendel and the Gene Idea 103–110
XV The Molecular Basis of Inheritance 111–118
XVI Gene Expression: From Gene to Protein 119–126
XVII Regulation of Gene Expression 127–130
SECTION I: EVOLUTION, THEMES OF BIOLOGY & SCIENTIFIC INQUIRY
,Questions 1–10
1. A researcher is studying a population of bacteria that has been exposed to a new antibiotic. Over several generations, the
bacteria become increasingly resistant. Which of the following best describes the mechanism driving this change?
A) Acquired characteristics inherited from the parent generation
B) Natural selection acting on existing genetic variation
C) Directed mutation in response to the antibiotic
D) Genetic drift reducing diversity in the population
E) Gene flow introducing resistance genes from other species
🔵 B — Natural selection acts on heritable variation present in the population. Bacteria with resistance-conferring
mutations survive and reproduce, passing these traits to offspring. Antibiotic exposure does not cause mutations; it selects
for pre-existing resistant variants. Acquired characteristics are not inherited (Lamarckian inheritance is rejected). Directed
mutation is not supported by evidence. Genetic drift is random and would not consistently produce resistance.
2. Which of the following is NOT a unifying theme of biology as described in the Campbell Biology AP Edition?
A) Evolution accounts for the unity and diversity of life
B) Living organisms use energy and matter to maintain organization
C) All biological systems are closed systems that do not exchange matter with their surroundings
D) Structure and function are correlated at all levels of biological organization
E) Feedback mechanisms regulate biological systems
🔵 C — Living systems are open systems that exchange energy and matter with their surroundings. Evolution, energy
processing, structure-function correlation, and regulation are all core themes of biology. The statement that biological
systems are closed is incorrect—organisms constantly take in energy and matter and release waste products.
3. Cells are the fundamental units of life. Which statement accurately distinguishes prokaryotic and eukaryotic cells?
A) Prokaryotic cells contain membrane-bound organelles, while eukaryotic cells do not
B) Eukaryotic cells have a nucleus; prokaryotic cells lack a true nucleus
C) Prokaryotic cells are always larger than eukaryotic cells
D) Eukaryotic cells lack ribosomes, while prokaryotic cells contain them
E) Prokaryotic cells contain linear DNA; eukaryotic cells contain circular DNA
🔵 B — The presence of a membrane-enclosed nucleus is the defining characteristic that distinguishes eukaryotic from
prokaryotic cells. Prokaryotic cells lack membrane-bound organelles, have circular DNA, and contain ribosomes (70S).
Eukaryotic cells have membrane-bound organelles (including the nucleus), linear DNA, and ribosomes (80S). Prokaryotic
cells are generally smaller than eukaryotic cells.
4. A scientist designs an experiment to test whether a new fertilizer increases plant growth. She divides 100 plants into two
groups: 50 receive the fertilizer, and 50 receive water only. All other conditions (light, temperature, soil type) are identical.
What is the independent variable in this experiment?
A) Plant growth rate
B) The amount of water given
C) The presence or absence of fertilizer
,D) The type of soil used
E) The temperature of the growth chamber
🔵 C — The independent variable is the factor that the researcher manipulates—in this case, the presence or absence of
fertilizer. Plant growth rate is the dependent variable (what is measured). Water, soil, and temperature are controlled
variables that must be kept constant.
5. A controlled experiment is one that:
A) Proceeds slowly enough that a scientist can make careful records
B) Tests experimental and control groups in parallel
C) Is repeated many times to ensure accuracy
D) Includes at least two groups, one differing from the other by a single variable
E) Both B and D
🔵 E — A controlled experiment compares an experimental group with a control group that differs by only one variable.
This allows the researcher to attribute any differences in outcome to the manipulated variable. Multiple repetitions
(replication) increase confidence in results but are not the defining feature of a controlled experiment.
6. Which level of biological organization is the simplest level that exhibits all characteristics of life?
A) Organelle
B) Cell
C) Tissue
D) Organ
E) Organism
🔵 B — The cell is the smallest unit of life that can perform all necessary functions of living organisms. Cells are the basic
structural and functional units of life. Organelles are not independently living; tissues, organs, and organisms are composed
of cells and represent higher levels of organization.
7. The process by which information in a gene directs the synthesis of a protein is called:
A) Replication
B) Transcription
C) Translation
D) Gene expression
E) Post-translational modification
🔵 D — Gene expression is the overall process by which genetic information flows from gene to protein. It encompasses
both transcription (DNA → mRNA) and translation (mRNA → protein). Replication is DNA copying. Post-translational
modification occurs after protein synthesis.
8. A biologist discovers a new organism that is unicellular, lacks a nucleus, and has a cell wall composed of peptidoglycan.
This organism most likely belongs to which domain?
A) Eukarya
B) Bacteria
C) Archaea
, D) Protista
E) Fungi
🔵 B — The presence of peptidoglycan in the cell wall is a characteristic feature of Bacteria. Archaea have cell walls but lack
peptidoglycan. Eukarya have a nucleus and membrane-bound organelles. Protista and Fungi are eukaryotic kingdoms.
9. Which of the following best describes the relationship between structure and function in biology?
A) Structure and function are unrelated; organisms can have any structure regardless of function
B) Function determines structure; organisms evolve structures based on what they need
C) Structure determines function; the physical form of a biological structure enables its specific function
D) Structure is fixed by genetics and never changes regardless of environmental conditions
E) Function is always more important than structure in determining evolutionary fitness
🔵 C — The correlation between structure and function is a fundamental theme in biology. The specific shape and
composition of a biological structure enable it to perform its function (e.g., the shape of enzymes allows them to bind
specific substrates; the structure of lungs maximizes gas exchange surface area).
10. Which of the following is an example of negative feedback in a biological system?
A) The release of oxytocin during childbirth, which stimulates stronger contractions
B) Blood glucose levels rising after a meal, triggering insulin release, which lowers blood glucose
C) A platelet releasing chemicals that attract more platelets to a wound site
D) An action potential triggering the opening of more sodium channels
E) Fruit ripening releasing ethylene, which stimulates more ripening
🔵 B — Negative feedback counteracts a change to maintain homeostasis. When blood glucose rises, insulin is released to
lower it, returning the system to its set point. All other options describe positive feedback, where a response amplifies the
initial stimulus.
SECTION II: THE CHEMICAL CONTEXT OF LIFE
Questions 11–18
11. The four most abundant elements in living organisms are:
A) Carbon, hydrogen, oxygen, and nitrogen
B) Carbon, hydrogen, oxygen, and phosphorus
C) Carbon, nitrogen, oxygen, and sulfur
D) Hydrogen, oxygen, nitrogen, and calcium
E) Carbon, oxygen, nitrogen, and potassium
🔵 A — Carbon, hydrogen, oxygen, and nitrogen make up approximately 96% of living matter. These elements are
essential for forming organic molecules. Phosphorus and sulfur are also important but are present in smaller amounts
(about 1% and 0.2-1%, respectively).
