ENV 101 GRADED MIDTERM – ENVIRONMENTAL
SCIENCE, ACTUAL QUESTIONS & CORRECT ANSWERS
UPDATED 2026 LATEST STUDY GUIDE - STRAIGHTER
LINE
THIS EXAM IS DESIGNED BASED ON THE CORE CURRICULUM AND COMMON
TESTING PATTERNS FOUND IN THE ENV 101 (ENVIRONMENTAL SCIENCE)
COURSE THROUGH STRAIGHTERLINE. IT COVERS 100 QUESTIONS DIVIDED INTO
KEY THEMATIC SECTIONS.
ENV 101: Environmental Science Midterm Exam
Prep Total Questions: 100
Format: Multiple Choice & Short Answer
Table of Contents
1. Section 1: Introduction to Environmental Science & Ethics (1-10)
2. Section 2: Ecology, Ecosystems, and Biomes (11-30)
3. Section 3: Population Dynamics (Human & Biological) (31-45)
4. Section 4: Evolution and Biodiversity (46-60)
5. Section 5: Energy Resources & Renewable Energy (61-75)
6. Section 6: Atmosphere, Climate Change & Air Pollution (76-90)
7. Section 7: Water, Soil, and Waste Management (91-100)
<a name="section1"></a>
Section 1: Introduction to Environmental Science & Ethics (1-10)
1. Which of the following is the best definition of "Sustainability"?
• Answer: Meeting the needs of the present without compromising the ability of
future generations to meet their own needs.
• Rationale: Sustainability focuses on the long-term health of the biosphere and
ensures that resources are not depleted beyond their rate of recovery.
2. What is an "Ecological Footprint"?
, • Answer: A measure of the amount of land and water required to provide the
resources a person or population consumes and to dispose of their waste.
• Rationale: It quantifies human impact on nature by comparing resource
consumption to the Earth's regenerative capacity.
3. Define the "Tragedy of the Commons."
• Answer: A situation where individuals acting in their own self-interest deplete a
shared resource, ultimately harming the entire group.
• Rationale: Originally described by Garrett Hardin, it explains why
unregulated open-access resources (like air or oceans) are prone to
overexploitation.
4. True or False: Environmental Science is exactly the same as Environmentalism.
• Answer: False.
• Rationale: Environmental science is an objective, interdisciplinary
study of the environment, while environmentalism is a social and
political movement.
5. What are the three pillars of the "Triple Bottom Line"?
• Answer: Social, Environmental, and Economic (People, Planet, Profit).
• Rationale: Sustainable development requires balancing these three
factors to be successful in the long term.
6. Who was the founder of the Sierra Club and an advocate for the Preservationist
ethic?
• Answer: John Muir.
• Rationale: Muir believed nature should be protected in its pristine state for its
own sake, rather than for human use.
7. Define "Anthropocentrism."
• Answer: A human-centered view of our relationship with the environment.
• Rationale: It evaluates environmental actions based solely on their impact on
human health and economics.
8. What is a "Hypothesis" in the scientific method?
• Answer: A testable, tentative explanation for a scientific observation.
• Rationale: To be scientific, a hypothesis must be capable of being
proven wrong (falsifiable).
, 9. In an experiment, what is the "Independent Variable"?
• Answer: The factor that the scientist manipulates or changes.
• Rationale: The independent variable is the "cause," while the dependent
variable is the "effect" being measured.
10. What is "Biocentrism"?
• Answer: The view that all living things (not just humans) have intrinsic value.
• Rationale: It extends ethical consideration to all living organisms regardless
of their utility to humans.
<a name="section2"></a>
Section 2: Ecology, Ecosystems, and Biomes (11-30)
11. What is the primary source of energy for most ecosystems on Earth?
• Answer: Solar Radiation (The Sun).
• Rationale: Photosynthesis converts solar energy into chemical energy, which
supports the rest of the food web.
12. Organisms that produce their own food are called .
• Answer: Autotrophs (or Primary Producers).
• Rationale: They use photosynthesis or chemosynthesis to create energy-rich
molecules.
13. In a food chain, how much energy is typically transferred from one trophic
level to the next?
• Answer: Approximately 10%.
• Rationale: The "10% Rule" explains why there are fewer top predators than
producers; the rest of the energy is lost as heat.
14. What is a "Niche"?
• Answer: The functional role and position of a species within its ecosystem.
• Rationale: A niche includes what the species eats, where it lives, and how it
interacts with other organisms.
15. Which biome is characterized by permafrost and low-growing vegetation?
SCIENCE, ACTUAL QUESTIONS & CORRECT ANSWERS
UPDATED 2026 LATEST STUDY GUIDE - STRAIGHTER
LINE
THIS EXAM IS DESIGNED BASED ON THE CORE CURRICULUM AND COMMON
TESTING PATTERNS FOUND IN THE ENV 101 (ENVIRONMENTAL SCIENCE)
COURSE THROUGH STRAIGHTERLINE. IT COVERS 100 QUESTIONS DIVIDED INTO
KEY THEMATIC SECTIONS.
ENV 101: Environmental Science Midterm Exam
Prep Total Questions: 100
Format: Multiple Choice & Short Answer
Table of Contents
1. Section 1: Introduction to Environmental Science & Ethics (1-10)
2. Section 2: Ecology, Ecosystems, and Biomes (11-30)
3. Section 3: Population Dynamics (Human & Biological) (31-45)
4. Section 4: Evolution and Biodiversity (46-60)
5. Section 5: Energy Resources & Renewable Energy (61-75)
6. Section 6: Atmosphere, Climate Change & Air Pollution (76-90)
7. Section 7: Water, Soil, and Waste Management (91-100)
<a name="section1"></a>
Section 1: Introduction to Environmental Science & Ethics (1-10)
1. Which of the following is the best definition of "Sustainability"?
• Answer: Meeting the needs of the present without compromising the ability of
future generations to meet their own needs.
• Rationale: Sustainability focuses on the long-term health of the biosphere and
ensures that resources are not depleted beyond their rate of recovery.
2. What is an "Ecological Footprint"?
, • Answer: A measure of the amount of land and water required to provide the
resources a person or population consumes and to dispose of their waste.
• Rationale: It quantifies human impact on nature by comparing resource
consumption to the Earth's regenerative capacity.
3. Define the "Tragedy of the Commons."
• Answer: A situation where individuals acting in their own self-interest deplete a
shared resource, ultimately harming the entire group.
• Rationale: Originally described by Garrett Hardin, it explains why
unregulated open-access resources (like air or oceans) are prone to
overexploitation.
4. True or False: Environmental Science is exactly the same as Environmentalism.
• Answer: False.
• Rationale: Environmental science is an objective, interdisciplinary
study of the environment, while environmentalism is a social and
political movement.
5. What are the three pillars of the "Triple Bottom Line"?
• Answer: Social, Environmental, and Economic (People, Planet, Profit).
• Rationale: Sustainable development requires balancing these three
factors to be successful in the long term.
6. Who was the founder of the Sierra Club and an advocate for the Preservationist
ethic?
• Answer: John Muir.
• Rationale: Muir believed nature should be protected in its pristine state for its
own sake, rather than for human use.
7. Define "Anthropocentrism."
• Answer: A human-centered view of our relationship with the environment.
• Rationale: It evaluates environmental actions based solely on their impact on
human health and economics.
8. What is a "Hypothesis" in the scientific method?
• Answer: A testable, tentative explanation for a scientific observation.
• Rationale: To be scientific, a hypothesis must be capable of being
proven wrong (falsifiable).
, 9. In an experiment, what is the "Independent Variable"?
• Answer: The factor that the scientist manipulates or changes.
• Rationale: The independent variable is the "cause," while the dependent
variable is the "effect" being measured.
10. What is "Biocentrism"?
• Answer: The view that all living things (not just humans) have intrinsic value.
• Rationale: It extends ethical consideration to all living organisms regardless
of their utility to humans.
<a name="section2"></a>
Section 2: Ecology, Ecosystems, and Biomes (11-30)
11. What is the primary source of energy for most ecosystems on Earth?
• Answer: Solar Radiation (The Sun).
• Rationale: Photosynthesis converts solar energy into chemical energy, which
supports the rest of the food web.
12. Organisms that produce their own food are called .
• Answer: Autotrophs (or Primary Producers).
• Rationale: They use photosynthesis or chemosynthesis to create energy-rich
molecules.
13. In a food chain, how much energy is typically transferred from one trophic
level to the next?
• Answer: Approximately 10%.
• Rationale: The "10% Rule" explains why there are fewer top predators than
producers; the rest of the energy is lost as heat.
14. What is a "Niche"?
• Answer: The functional role and position of a species within its ecosystem.
• Rationale: A niche includes what the species eats, where it lives, and how it
interacts with other organisms.
15. Which biome is characterized by permafrost and low-growing vegetation?
