ENV 101 Exam 3 V2 | ENV 101
Environmental Science | StraighterLine |
Q&A with Rationale (StraighterLine
ENV101 Exam 3)
1. Which of the following represents the largest reservoir of liquid freshwater on Earth?
A. Lakes and rivers
B. Glaciers and ice caps
C. Atmospheric water vapor
D. Groundwater
Answer: D
Rationale: Groundwater accounts for approximately 95 percent of all liquid freshwater
available on Earth. While glaciers and ice caps hold more total freshwater, they are in a
solid state and not readily accessible for use. Surface waters like lakes and rivers contain
significantly less volume compared to the vast underground aquifers.
2. What is the primary cause of cultural eutrophication in aquatic ecosystems?
A. High levels of dissolved oxygen
B. Thermal pollution from power plants
C. Introduction of invasive predatory fish
D. Excessive nutrient runoff from fertilizers
,Answer: D
Rationale: Cultural eutrophication occurs when human activities accelerate the input of
nutrients, specifically nitrogen and phosphorus, into water bodies. This excess of nutrients
triggers massive algal blooms that eventually die and decompose. The decomposition
process consumes dissolved oxygen, creating hypoxic conditions that threaten aquatic life.
3. The ‘cradle-to-grave’ tracking of hazardous waste is a requirement established by which
federal legislation?
A. The Clean Water Act (CWA)
B. The Safe Drinking Water Act (SDWA)
C. The Resource Conservation and Recovery Act (RCRA)
D. The Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA)
Answer: C
Rationale: The Resource Conservation and Recovery Act (RCRA) provides the legal
framework for managing non-hazardous and hazardous solid wastes. It specifically
mandates a system to track hazardous waste from its generation point to its final disposal
site. This ensures that hazardous materials are accounted for throughout their entire life
cycle to prevent illegal dumping.
, 4. Which layer of the atmosphere contains the ozone layer that protects Earth from
ultraviolet radiation?
A. Troposphere
B. Thermosphere
C. Mesosphere
D. Stratosphere
Answer: D
Rationale: The stratosphere is the second major layer of Earth’s atmosphere, located
above the troposphere. It contains a high concentration of ozone (O3) molecules that
absorb the majority of the sun’s harmful ultraviolet (UV) radiation. Without this protective
layer, life on the surface would be subjected to damaging levels of mutagenic radiation.
5. Which air pollutant is a colorless, odorless gas that binds to hemoglobin, preventing
oxygen transport in the blood?
A. Carbon monoxide
B. Carbon dioxide
C. Sulfur dioxide
D. Nitrogen dioxide
Answer: A
Environmental Science | StraighterLine |
Q&A with Rationale (StraighterLine
ENV101 Exam 3)
1. Which of the following represents the largest reservoir of liquid freshwater on Earth?
A. Lakes and rivers
B. Glaciers and ice caps
C. Atmospheric water vapor
D. Groundwater
Answer: D
Rationale: Groundwater accounts for approximately 95 percent of all liquid freshwater
available on Earth. While glaciers and ice caps hold more total freshwater, they are in a
solid state and not readily accessible for use. Surface waters like lakes and rivers contain
significantly less volume compared to the vast underground aquifers.
2. What is the primary cause of cultural eutrophication in aquatic ecosystems?
A. High levels of dissolved oxygen
B. Thermal pollution from power plants
C. Introduction of invasive predatory fish
D. Excessive nutrient runoff from fertilizers
,Answer: D
Rationale: Cultural eutrophication occurs when human activities accelerate the input of
nutrients, specifically nitrogen and phosphorus, into water bodies. This excess of nutrients
triggers massive algal blooms that eventually die and decompose. The decomposition
process consumes dissolved oxygen, creating hypoxic conditions that threaten aquatic life.
3. The ‘cradle-to-grave’ tracking of hazardous waste is a requirement established by which
federal legislation?
A. The Clean Water Act (CWA)
B. The Safe Drinking Water Act (SDWA)
C. The Resource Conservation and Recovery Act (RCRA)
D. The Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA)
Answer: C
Rationale: The Resource Conservation and Recovery Act (RCRA) provides the legal
framework for managing non-hazardous and hazardous solid wastes. It specifically
mandates a system to track hazardous waste from its generation point to its final disposal
site. This ensures that hazardous materials are accounted for throughout their entire life
cycle to prevent illegal dumping.
, 4. Which layer of the atmosphere contains the ozone layer that protects Earth from
ultraviolet radiation?
A. Troposphere
B. Thermosphere
C. Mesosphere
D. Stratosphere
Answer: D
Rationale: The stratosphere is the second major layer of Earth’s atmosphere, located
above the troposphere. It contains a high concentration of ozone (O3) molecules that
absorb the majority of the sun’s harmful ultraviolet (UV) radiation. Without this protective
layer, life on the surface would be subjected to damaging levels of mutagenic radiation.
5. Which air pollutant is a colorless, odorless gas that binds to hemoglobin, preventing
oxygen transport in the blood?
A. Carbon monoxide
B. Carbon dioxide
C. Sulfur dioxide
D. Nitrogen dioxide
Answer: A
