ENV 101 Exam 2 V3 | ENV 101
Environmental Science | StraighterLine |
Q&A with Rationale (StraighterLine
ENV101 Exam 2)
1. Which process describes the mechanism by which individuals with certain inherited traits
tend to survive and reproduce at higher rates than other individuals because of those traits?
A. Genetic Drift
B. Natural Selection
C. Artificial Selection
D. Mutation Rate
Answer: B
Rationale: Natural selection is the primary mechanism of evolution proposed by Charles
Darwin. It occurs when individuals with advantageous traits are more likely to survive and
pass those traits to the next generation. Over time, this process leads to adaptations that
better suit a population to its specific environment.
2. A species that has a wide range of tolerance and can live in many different places, eat a
variety of foods, and tolerate a wide range of environmental conditions is known as a:
A. Specialist species
B. Keystone species
,C. Generalist species
D. Indicator species
Answer: C
Rationale: Generalist species, such as cockroaches or raccoons, possess broad niches that
allow them to thrive in diverse habitats. Unlike specialists, they do not rely on a single food
source or narrow temperature range. This flexibility often makes them more resilient to
environmental changes compared to species with narrow niches.
3. The functional role of a species within its ecosystem, including its use of resources and
relationships with other species, is referred to as its:
A. Habitat
B. Trophic level
C. Ecological niche
D. Biotype
Answer: C
Rationale: An ecological niche encompasses everything a species does and needs to
survive and reproduce. It differs from a habitat, which is simply the physical location where
the organism lives. Understanding a species’ niche helps ecologists predict how it will
interact with other organisms and respond to resource competition.
, 4. When two species compete for the same limiting resource, one eventually outcompetes
the other, leading to the latter’s local extinction. This concept is known as:
A. Resource partitioning
B. Mutualism
C. Commensalism
D. Competitive exclusion
Answer: D
Rationale: The competitive exclusion principle states that two species cannot occupy the
exact same niche in the same habitat indefinitely. If resources are limited, the more
efficient competitor will eliminate the other. This drive often leads to resource partitioning,
where species evolve to use different parts of a resource to avoid direct competition.
5. Identify the type of symbiosis where one organism benefits while the other is neither
helped nor harmed.
A. Mutualism
B. Parasitism
C. Competition
D. Commensalism
Answer: D
Environmental Science | StraighterLine |
Q&A with Rationale (StraighterLine
ENV101 Exam 2)
1. Which process describes the mechanism by which individuals with certain inherited traits
tend to survive and reproduce at higher rates than other individuals because of those traits?
A. Genetic Drift
B. Natural Selection
C. Artificial Selection
D. Mutation Rate
Answer: B
Rationale: Natural selection is the primary mechanism of evolution proposed by Charles
Darwin. It occurs when individuals with advantageous traits are more likely to survive and
pass those traits to the next generation. Over time, this process leads to adaptations that
better suit a population to its specific environment.
2. A species that has a wide range of tolerance and can live in many different places, eat a
variety of foods, and tolerate a wide range of environmental conditions is known as a:
A. Specialist species
B. Keystone species
,C. Generalist species
D. Indicator species
Answer: C
Rationale: Generalist species, such as cockroaches or raccoons, possess broad niches that
allow them to thrive in diverse habitats. Unlike specialists, they do not rely on a single food
source or narrow temperature range. This flexibility often makes them more resilient to
environmental changes compared to species with narrow niches.
3. The functional role of a species within its ecosystem, including its use of resources and
relationships with other species, is referred to as its:
A. Habitat
B. Trophic level
C. Ecological niche
D. Biotype
Answer: C
Rationale: An ecological niche encompasses everything a species does and needs to
survive and reproduce. It differs from a habitat, which is simply the physical location where
the organism lives. Understanding a species’ niche helps ecologists predict how it will
interact with other organisms and respond to resource competition.
, 4. When two species compete for the same limiting resource, one eventually outcompetes
the other, leading to the latter’s local extinction. This concept is known as:
A. Resource partitioning
B. Mutualism
C. Commensalism
D. Competitive exclusion
Answer: D
Rationale: The competitive exclusion principle states that two species cannot occupy the
exact same niche in the same habitat indefinitely. If resources are limited, the more
efficient competitor will eliminate the other. This drive often leads to resource partitioning,
where species evolve to use different parts of a resource to avoid direct competition.
5. Identify the type of symbiosis where one organism benefits while the other is neither
helped nor harmed.
A. Mutualism
B. Parasitism
C. Competition
D. Commensalism
Answer: D
