BIS 2B Final Exam Questions with Correct Answers Latest Update 2026/2027
Intraspecific - Answers Interactions between members of the same species (Individual
Interactions).
Interspecific - Answers Interactions between individuals from two different species.
-Sources of selection (evolution)
-Determine distribution and abundance of species (ecology)
-Important in determining population regulation - Answers Why should we study interspecific
interactions?
Competition - Answers Each species has a negative effect on the other.
(-,-)
Amensalism - Answers One species injured but the interaction, the other is unaffected by the
other species. (-,0)
Predation/Parasitism/Herbivory - Answers One species benefits at the cost of another. (+,-)
Commensalism - Answers One species benefits and the other is unaffected. (+,0)
-Often refers to mobile associates.
Facilitation - Answers One species benefits and the other is unaffected. (+,0)
-Often refers to sessile associates
Mutualism - Answers Both species benefit. (+,+)
-Have both costs and benefits, and the outcome is only mutualistic when benefits outweigh
costs for both species.
Obligate Mutualism - Answers Mutually beneficial interaction between two species in which
each species REQUIRES the other to persist.
ex: Yucca plant and Yucca Moth
Facultative Mutualism - Answers Beneficial interaction between two species in which each
species benefits, but does not require the other to persist.
-More likely to be conditional.
Conditionality - Answers When outcomes of species interactions depend on the environment.
Satiation - Answers Number of prey is so abundant that predators cannot possibly eat them all.
, -Underground networks to allow escape from larger predators
-Refuge at High Densities: Safety in Numbers; reduces efficiency of predators - Answers What
are the different types of refuges?
Competition - Answers When individuals use a shared resource that is in short supply (not
enough resource for all).
-Results in decreased rates of growth, survival or reproduction that alter population growth rates.
Interspecific Competition - Answers Competition between members of different species.
Intraspecific Competition - Answers Competition between members of the same species.
Competitive Exclusion Principle - Answers Two species that use the same resources in the
same way cannot coexist. One will drive the other to extinction.
Competitors can coexist when resources are "partitioned". - Answers What is an exception to
the Competitive Exclusion Principle?
Exploitative Competition - Answers Resource depletion. What one individuals uses, another
cannot. Individuals need not encounter one another to compete.
Interference Competition - Answers Competitors confront each other, and harass, chase or
otherwise prohibit others from using resources.
The Fundamental Niche - Answers The range of resource types (ex: seeds of different sizes)
that are used by a species in the absence of interactions with other species
Degree of niche overlap. - Answers What determines coexistence?
Niche Overlap - Answers Corresponds to the shaded region of overlap between resource use
curves for two competing species.
Resource Partitioning - Answers Relatively little shared resources between species, making it
easier for the two to coexist.
Competitive Exclusion - Answers When there is large niche overlap, one species will out-
compete the other.
Fundamental Niche - Answers Defined by physical conditions (and resource conditions) under
which a species can persist.
Realized Niche - Answers Alteration of fundamental niche by species interactions.
-Species actually occurs over a narrower range of nutrients due to competition from other
species.
Intraspecific - Answers Interactions between members of the same species (Individual
Interactions).
Interspecific - Answers Interactions between individuals from two different species.
-Sources of selection (evolution)
-Determine distribution and abundance of species (ecology)
-Important in determining population regulation - Answers Why should we study interspecific
interactions?
Competition - Answers Each species has a negative effect on the other.
(-,-)
Amensalism - Answers One species injured but the interaction, the other is unaffected by the
other species. (-,0)
Predation/Parasitism/Herbivory - Answers One species benefits at the cost of another. (+,-)
Commensalism - Answers One species benefits and the other is unaffected. (+,0)
-Often refers to mobile associates.
Facilitation - Answers One species benefits and the other is unaffected. (+,0)
-Often refers to sessile associates
Mutualism - Answers Both species benefit. (+,+)
-Have both costs and benefits, and the outcome is only mutualistic when benefits outweigh
costs for both species.
Obligate Mutualism - Answers Mutually beneficial interaction between two species in which
each species REQUIRES the other to persist.
ex: Yucca plant and Yucca Moth
Facultative Mutualism - Answers Beneficial interaction between two species in which each
species benefits, but does not require the other to persist.
-More likely to be conditional.
Conditionality - Answers When outcomes of species interactions depend on the environment.
Satiation - Answers Number of prey is so abundant that predators cannot possibly eat them all.
, -Underground networks to allow escape from larger predators
-Refuge at High Densities: Safety in Numbers; reduces efficiency of predators - Answers What
are the different types of refuges?
Competition - Answers When individuals use a shared resource that is in short supply (not
enough resource for all).
-Results in decreased rates of growth, survival or reproduction that alter population growth rates.
Interspecific Competition - Answers Competition between members of different species.
Intraspecific Competition - Answers Competition between members of the same species.
Competitive Exclusion Principle - Answers Two species that use the same resources in the
same way cannot coexist. One will drive the other to extinction.
Competitors can coexist when resources are "partitioned". - Answers What is an exception to
the Competitive Exclusion Principle?
Exploitative Competition - Answers Resource depletion. What one individuals uses, another
cannot. Individuals need not encounter one another to compete.
Interference Competition - Answers Competitors confront each other, and harass, chase or
otherwise prohibit others from using resources.
The Fundamental Niche - Answers The range of resource types (ex: seeds of different sizes)
that are used by a species in the absence of interactions with other species
Degree of niche overlap. - Answers What determines coexistence?
Niche Overlap - Answers Corresponds to the shaded region of overlap between resource use
curves for two competing species.
Resource Partitioning - Answers Relatively little shared resources between species, making it
easier for the two to coexist.
Competitive Exclusion - Answers When there is large niche overlap, one species will out-
compete the other.
Fundamental Niche - Answers Defined by physical conditions (and resource conditions) under
which a species can persist.
Realized Niche - Answers Alteration of fundamental niche by species interactions.
-Species actually occurs over a narrower range of nutrients due to competition from other
species.
