Environmental Science (2026) Q&A | StraighterLine
1. Which of the following is NOT a defining characteristic shared by all living
organisms?
A) The ability to move from one location to another
B) Cellular organization
C) Metabolism
D) Homeostasis
Correct Answer: The ability to move from one location to another
Rationale: While many organisms can move, mobility is not universal. All living
things exhibit cellular organization, metabolism, homeostasis, growth,
reproduction, and response to stimuli. Movement is not a requirement for life.
2. The chemical processes that occur within a living organism to maintain life
are collectively termed:
A) Homeostasis
B) Metabolism
C) Adaptation
D) Reproduction
Correct Answer: Metabolism
Rationale: Metabolism encompasses all chemical reactions in an organism,
including breaking down nutrients for energy and building cellular components.
,Homeostasis is internal stability, adaptation is evolutionary change, and
reproduction is producing offspring.
3. Maintaining a stable internal environment despite changing external
conditions is the definition of:
A) Natural selection
B) Speciation
C) Homeostasis
D) Evolution
Correct Answer: Homeostasis
Rationale: Homeostasis is crucial for survival; examples include temperature
regulation and pH balance. Natural selection and evolution operate over
generations, not within an individual’s lifetime. Speciation is the formation of
new species.
4. A single bacterium in a pond is considered a(n):
A) Abiotic factor
B) Biotic factor
C) Ecosystem service
D) Keystone species
Correct Answer: Biotic factor
, Rationale: Biotic factors include all living components of an environment—
bacteria, plants, animals. Abiotic factors are nonliving (sunlight, water).
Ecosystem services are benefits to humans; a keystone species has a
disproportionate ecological role.
5. The number of different species present in a given area is referred to as:
A) Species richness
B) Species evenness
C) Genetic diversity
D) Ecosystem diversity
Correct Answer: Species richness
Rationale: Species richness counts the variety of species regardless of their
population sizes. Evenness describes how equally individuals are distributed
among species. Genetic diversity is variation within a species; ecosystem
diversity refers to habitat variety.
6. How equally individuals are distributed among the species in a community is
measured by:
A) Species richness
B) Species evenness
C) Population density
D) Carrying capacity
Correct Answer: Species evenness