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CAMPBELL BIOLOGY AP EDITION, 11TH
EDITION | PRACTICE QUESTIONS AND
VERIFIED ANSWERS | EXAM REVIEW | STUDY
GUIDE.
Table of Contents
1. Exam Overview and AP Biology Framework
2. Unit 1: Chemistry of Life
3. Unit 2: Cell Structure and Function
4. Unit 3: Cellular Energetics
5. Unit 4: Cell Communication and Cell Cycle
6. Unit 5: Heredity
7. Unit 6: Gene Expression and Regulation
8. Unit 7: Natural Selection
9. Unit 8: Ecology
10. Practice Questions with Detailed Solutions
11. Study Strategies and Exam-Day Tips
EXAM OVERVIEW AND AP BIOLOGY FRAMEWORK
The AP Biology exam consists of two sections. Section I includes 60 multiple-choice questions
(90 minutes) and 6 grid-in questions (10 minutes). Section II includes 2 long free-response
questions and 4 short free-response questions (90 minutes plus a 10-minute reading period). The
exam is scored on a 1–5 scale, with a score of 3 or higher generally considered passing. The
course is organized around four Big Ideas: Evolution, Energetics, Information Storage and
Transmission, and Systems Interactions. The eight units are: Chemistry of Life, Cell Structure
and Function, Cellular Energetics, Cell Communication and Cell Cycle, Heredity, Gene
Expression and Regulation, Natural Selection, and Ecology.
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UNIT 1: CHEMISTRY OF LIFE
Question 1: Which of the following types of cells utilize deoxyribonucleic acid (DNA) as their
genetic material but do not have their DNA encased within a nuclear envelope?
A) Animal
B) Plant
C) Archaean
D) Fungi
Correct Answer: C) Archaean
Archaea are prokaryotes, meaning they lack a membrane-bound nucleus. Their DNA is not
encased within a nuclear envelope. Animal, plant, and fungal cells are eukaryotes and have a
true nucleus that encloses their DNA.
Question 2: The main source of energy for producers in an ecosystem comes from:
A) Solar energy
B) Other animals as a food source
C) The atmosphere
D) Plants
Correct Answer: A) Solar energy
Producers (autotrophs) convert solar energy into chemical energy through photosynthesis. This
is the primary source of energy for nearly all ecosystems on Earth.
Question 3: A localized group of organisms that belong to the same species is called a:
A) Biosystem
B) Community
C) Population
D) Ecosystem
Correct Answer: C) Population
A population is a group of individuals of the same species living in the same area at the same
time. A community includes all populations in an area. An ecosystem includes both living and
nonliving components.
Question 4: Which subatomic particle determines the atomic number of an element?
A) Neutron
B) Proton
C) Electron
D) Photon
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Correct Answer: B) Proton
The atomic number is the number of protons in the nucleus of an atom. This number is unique to
each element and determines its identity.
Question 5: Which of the following best describes the difference between an element and a
compound?
A) Elements are made of molecules; compounds are made of atoms.
B) An element is a pure substance consisting of one type of atom; a compound is a substance
consisting of two or more different elements chemically bonded.
C) Elements are found only in living things; compounds are found only in nonliving things.
D) Elements are gases; compounds are solids.
Correct Answer: B) An element is a pure substance consisting of one type of atom; a
compound is a substance consisting of two or more different elements chemically bonded.
This is the fundamental distinction between elements and compounds. Elements cannot be broken
down into simpler substances by chemical means, while compounds can be broken down into
their constituent elements.
Question 6: What are the four most abundant elements found in living systems?
A) Carbon, hydrogen, oxygen, nitrogen
B) Carbon, sodium, chlorine, potassium
C) Oxygen, calcium, phosphorus, sulfur
D) Hydrogen, helium, lithium, beryllium
Correct Answer: A) Carbon, hydrogen, oxygen, nitrogen
These four elements make up approximately 96% of the mass of living organisms. Carbon is the
backbone of organic molecules, while hydrogen, oxygen, and nitrogen are essential components
of biological macromolecules.
Question 7: How many covalent bonds can a hydrogen atom form?
A) 1
B) 2
C) 3
D) 4
Correct Answer: A) 1
A hydrogen atom has one electron and can form one covalent bond by sharing its electron with
another atom. This is why hydrogen is often found at the periphery of organic molecules.
Question 8: Which of the following is a hydrophobic molecule?
A) Glucose
B) Sodium chloride
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C) Cholesterol
D) Water
Correct Answer: C) Cholesterol
Cholesterol is a lipid, which is hydrophobic (water-fearing) because it is nonpolar. Glucose and
sodium chloride are hydrophilic (water-loving). Water itself is polar and hydrophilic.
Question 9: The process by which the information in a gene directs the synthesis of a protein is
called:
A) Gene expression
B) Replication
C) Post-translation modification
D) Cloning
Correct Answer: A) Gene expression
Gene expression is the process by which the information encoded in a gene is used to direct the
synthesis of a protein. It involves transcription (DNA to mRNA) and translation (mRNA to
protein).
Question 10: Once labor begins in childbirth, contractions increase in intensity and frequency
until delivery. This is an example of:
A) A bioinformatic system
B) Positive feedback
C) Negative feedback
D) Feedback inhibition
Correct Answer: B) Positive feedback
Positive feedback occurs when the response to a stimulus amplifies the original stimulus. In
childbirth, each contraction stimulates stronger contractions until delivery. This is a classic
example of positive feedback.
UNIT 2: CELL STRUCTURE AND FUNCTION
Question 11: When biologists wish to study the internal ultrastructure of cells, they can achieve
the finest resolution by using:
A) A phase-contrast light microscope
B) A scanning electron microscope
C) A transmission electron microscope
D) A confocal fluorescence microscope
Correct Answer: C) A transmission electron microscope
Transmission electron microscopy (TEM) provides the highest resolution for studying internal
CAMPBELL BIOLOGY AP EDITION, 11TH
EDITION | PRACTICE QUESTIONS AND
VERIFIED ANSWERS | EXAM REVIEW | STUDY
GUIDE.
Table of Contents
1. Exam Overview and AP Biology Framework
2. Unit 1: Chemistry of Life
3. Unit 2: Cell Structure and Function
4. Unit 3: Cellular Energetics
5. Unit 4: Cell Communication and Cell Cycle
6. Unit 5: Heredity
7. Unit 6: Gene Expression and Regulation
8. Unit 7: Natural Selection
9. Unit 8: Ecology
10. Practice Questions with Detailed Solutions
11. Study Strategies and Exam-Day Tips
EXAM OVERVIEW AND AP BIOLOGY FRAMEWORK
The AP Biology exam consists of two sections. Section I includes 60 multiple-choice questions
(90 minutes) and 6 grid-in questions (10 minutes). Section II includes 2 long free-response
questions and 4 short free-response questions (90 minutes plus a 10-minute reading period). The
exam is scored on a 1–5 scale, with a score of 3 or higher generally considered passing. The
course is organized around four Big Ideas: Evolution, Energetics, Information Storage and
Transmission, and Systems Interactions. The eight units are: Chemistry of Life, Cell Structure
and Function, Cellular Energetics, Cell Communication and Cell Cycle, Heredity, Gene
Expression and Regulation, Natural Selection, and Ecology.
, Page |2
UNIT 1: CHEMISTRY OF LIFE
Question 1: Which of the following types of cells utilize deoxyribonucleic acid (DNA) as their
genetic material but do not have their DNA encased within a nuclear envelope?
A) Animal
B) Plant
C) Archaean
D) Fungi
Correct Answer: C) Archaean
Archaea are prokaryotes, meaning they lack a membrane-bound nucleus. Their DNA is not
encased within a nuclear envelope. Animal, plant, and fungal cells are eukaryotes and have a
true nucleus that encloses their DNA.
Question 2: The main source of energy for producers in an ecosystem comes from:
A) Solar energy
B) Other animals as a food source
C) The atmosphere
D) Plants
Correct Answer: A) Solar energy
Producers (autotrophs) convert solar energy into chemical energy through photosynthesis. This
is the primary source of energy for nearly all ecosystems on Earth.
Question 3: A localized group of organisms that belong to the same species is called a:
A) Biosystem
B) Community
C) Population
D) Ecosystem
Correct Answer: C) Population
A population is a group of individuals of the same species living in the same area at the same
time. A community includes all populations in an area. An ecosystem includes both living and
nonliving components.
Question 4: Which subatomic particle determines the atomic number of an element?
A) Neutron
B) Proton
C) Electron
D) Photon
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Correct Answer: B) Proton
The atomic number is the number of protons in the nucleus of an atom. This number is unique to
each element and determines its identity.
Question 5: Which of the following best describes the difference between an element and a
compound?
A) Elements are made of molecules; compounds are made of atoms.
B) An element is a pure substance consisting of one type of atom; a compound is a substance
consisting of two or more different elements chemically bonded.
C) Elements are found only in living things; compounds are found only in nonliving things.
D) Elements are gases; compounds are solids.
Correct Answer: B) An element is a pure substance consisting of one type of atom; a
compound is a substance consisting of two or more different elements chemically bonded.
This is the fundamental distinction between elements and compounds. Elements cannot be broken
down into simpler substances by chemical means, while compounds can be broken down into
their constituent elements.
Question 6: What are the four most abundant elements found in living systems?
A) Carbon, hydrogen, oxygen, nitrogen
B) Carbon, sodium, chlorine, potassium
C) Oxygen, calcium, phosphorus, sulfur
D) Hydrogen, helium, lithium, beryllium
Correct Answer: A) Carbon, hydrogen, oxygen, nitrogen
These four elements make up approximately 96% of the mass of living organisms. Carbon is the
backbone of organic molecules, while hydrogen, oxygen, and nitrogen are essential components
of biological macromolecules.
Question 7: How many covalent bonds can a hydrogen atom form?
A) 1
B) 2
C) 3
D) 4
Correct Answer: A) 1
A hydrogen atom has one electron and can form one covalent bond by sharing its electron with
another atom. This is why hydrogen is often found at the periphery of organic molecules.
Question 8: Which of the following is a hydrophobic molecule?
A) Glucose
B) Sodium chloride
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C) Cholesterol
D) Water
Correct Answer: C) Cholesterol
Cholesterol is a lipid, which is hydrophobic (water-fearing) because it is nonpolar. Glucose and
sodium chloride are hydrophilic (water-loving). Water itself is polar and hydrophilic.
Question 9: The process by which the information in a gene directs the synthesis of a protein is
called:
A) Gene expression
B) Replication
C) Post-translation modification
D) Cloning
Correct Answer: A) Gene expression
Gene expression is the process by which the information encoded in a gene is used to direct the
synthesis of a protein. It involves transcription (DNA to mRNA) and translation (mRNA to
protein).
Question 10: Once labor begins in childbirth, contractions increase in intensity and frequency
until delivery. This is an example of:
A) A bioinformatic system
B) Positive feedback
C) Negative feedback
D) Feedback inhibition
Correct Answer: B) Positive feedback
Positive feedback occurs when the response to a stimulus amplifies the original stimulus. In
childbirth, each contraction stimulates stronger contractions until delivery. This is a classic
example of positive feedback.
UNIT 2: CELL STRUCTURE AND FUNCTION
Question 11: When biologists wish to study the internal ultrastructure of cells, they can achieve
the finest resolution by using:
A) A phase-contrast light microscope
B) A scanning electron microscope
C) A transmission electron microscope
D) A confocal fluorescence microscope
Correct Answer: C) A transmission electron microscope
Transmission electron microscopy (TEM) provides the highest resolution for studying internal
