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ASU BIO 182 Exam 2 Study Guide 2025 – Biology II Review,
Practice Questions, Flashcards & Key Concepts Explained
ASU BIO 182 exam 2 study guide 2025
BIO 182 exam 2 ASU review
ASU biology 182 practice test
BIO 182 exam 2 questions and answers
ASU BIO 182 flashcards and notes
Arizona State University biology 182 exam 2
how to pass ASU BIO 182 exam 2
What is Cladogenesis? - ANSWER-A pattern of speciation
- Branching evolution
- Branching off of one or more new species from a parent species that continues to exist
- increases the number of species
Hence the increase of biological diversity
E.g. Adaptive radiation
What is allopathic speciation? - ANSWER-- Population splits into two geographically isolated groups
- Genetic changes accumulate
- Cumulative differences prevent breeding between individuals of the two populations
- Two species have evolved
What is the key to speciation? - ANSWER-Reproductive isolation
- even w/o geographic isolation
What is sympatric speciation? - ANSWER-When populations are in the same physical area
,2|Page
•But become genetically isolated by genetic events
• e.g., polyploidy
•Or behavioral or other isolating mechanisms • e.g., mating patterns, feeding behavior
What is Parapatric speciation? - ANSWER-Contiguous populations
•But individuals more likely to mate with local neighbors
• gene flow limited
•Helped by heterogeneous environment and disruptive selection
What are the types of reproductive isolation? - ANSWER-Prezygotic and Postzygotic
What are the advantages of being complex? - ANSWER-- If small enough, you can get oxygen to your
cells through diffusion
-If not, a specialized respiratory systems is needed
Being bigger (more complex)
- can eat larger things
- are harder to kill
- able to exploit new niches
Does natural selection lead to even greater complexity? - ANSWER-Evolution is a non-directional process
What is the biological species concept? - ANSWER-A species is a population or group of populations
whose members have the potential to interbreed in nature and produce viable, fertile offspring
• ... Are reproductively isolated from other such populations
What is the Ecological species concept? - ANSWER-• defines a species in terms of it's ecological niche
• a species' niche depends on its unique adaptations to its role in the biological community
What is the genealogical concept? - ANSWER-• defines a species as a set of organisms with a unique
genetic history
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What is the morphological species concept? - ANSWER-defines a species in terms of its unique structural
features (its morphology)
How do groups undergo speciation? (Become reproductively isolated) - ANSWER-Two populations
become so different that they are considered different species
A population becomes so different from its ancestral state that it is considered another species
What is anagenesis? - ANSWER-A pattern of speciation
- Phyletic evolution
- is an accumulation of changes with the transformation of one species to another
- these processes can lead to change within a population (or species)
- but has no increase in number of species
What is Prezygotic (reproductive isolation)? - ANSWER-Impede mating between species or hinder
fertilization if mating is attempted
What is Postzygotic (reproductive isolation)? - ANSWER-If fertilization occurs, presents hybrids from
developing into a viable, fertile adult
What are some prezygotic barriers? - ANSWER-Habitat isolation - two species live in different habitats (in
the same area) and rarely meet (spider tree and trunk spiders )
Behavioral Isolation - species do no recognize signals or mating cues of other species (spiders, dancing vs
drumming)
Temporal Isolation - species breed at different times (times of day, seasons)
Mechanical Isolation - species are anatomically incompatible
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Gametic Isolation - species gametes are incompatible
What are the postzygotic barriers? - ANSWER-Reduced hybrid viability - hybrids fail to develop or reach
sexual maturity, hybrids are mostly or completely sterile, hybrid breakdown - offspring of hybrids have
reduced viability or fertility
What are the different models of speciation? - ANSWER-Allopatric - Geographically isolated groups--
>become reproductively isolated
Sympatric - Genetic or behavioral patterns while living in same area
Parapatric - pop. Spread over large area, but individuals mate with closest geographic neighbor--
>reduces gene flow and varying selection pressures
What is Coevolution? - ANSWER-An adaption in one species may lead to the evolution of an adaptation
in a species it interacts with
What is convergent evolution? - ANSWER-Independently evolved traits subjected to similar selection
pressures may become superficially similar
- Similar traits generated by convergent evolution are called homoplastic traits or homoplasies
What is a monophyletic group? - ANSWER-Graph that includes the common ancestor and all of its
descendents
What is a paraphyletic group? - ANSWER-Graph that includes the common ancestor and some but not all
of its descendants
What is a polyphyletic group? - ANSWER-Graph that does not include the common ancestor
What is a synapomorphies? - ANSWER-Shared derived characters
What is Parsimony? - ANSWER-Choosing the hypothesis that has the lowest number of changes
ASU BIO 182 Exam 2 Study Guide 2025 – Biology II Review,
Practice Questions, Flashcards & Key Concepts Explained
ASU BIO 182 exam 2 study guide 2025
BIO 182 exam 2 ASU review
ASU biology 182 practice test
BIO 182 exam 2 questions and answers
ASU BIO 182 flashcards and notes
Arizona State University biology 182 exam 2
how to pass ASU BIO 182 exam 2
What is Cladogenesis? - ANSWER-A pattern of speciation
- Branching evolution
- Branching off of one or more new species from a parent species that continues to exist
- increases the number of species
Hence the increase of biological diversity
E.g. Adaptive radiation
What is allopathic speciation? - ANSWER-- Population splits into two geographically isolated groups
- Genetic changes accumulate
- Cumulative differences prevent breeding between individuals of the two populations
- Two species have evolved
What is the key to speciation? - ANSWER-Reproductive isolation
- even w/o geographic isolation
What is sympatric speciation? - ANSWER-When populations are in the same physical area
,2|Page
•But become genetically isolated by genetic events
• e.g., polyploidy
•Or behavioral or other isolating mechanisms • e.g., mating patterns, feeding behavior
What is Parapatric speciation? - ANSWER-Contiguous populations
•But individuals more likely to mate with local neighbors
• gene flow limited
•Helped by heterogeneous environment and disruptive selection
What are the types of reproductive isolation? - ANSWER-Prezygotic and Postzygotic
What are the advantages of being complex? - ANSWER-- If small enough, you can get oxygen to your
cells through diffusion
-If not, a specialized respiratory systems is needed
Being bigger (more complex)
- can eat larger things
- are harder to kill
- able to exploit new niches
Does natural selection lead to even greater complexity? - ANSWER-Evolution is a non-directional process
What is the biological species concept? - ANSWER-A species is a population or group of populations
whose members have the potential to interbreed in nature and produce viable, fertile offspring
• ... Are reproductively isolated from other such populations
What is the Ecological species concept? - ANSWER-• defines a species in terms of it's ecological niche
• a species' niche depends on its unique adaptations to its role in the biological community
What is the genealogical concept? - ANSWER-• defines a species as a set of organisms with a unique
genetic history
,3|Page
What is the morphological species concept? - ANSWER-defines a species in terms of its unique structural
features (its morphology)
How do groups undergo speciation? (Become reproductively isolated) - ANSWER-Two populations
become so different that they are considered different species
A population becomes so different from its ancestral state that it is considered another species
What is anagenesis? - ANSWER-A pattern of speciation
- Phyletic evolution
- is an accumulation of changes with the transformation of one species to another
- these processes can lead to change within a population (or species)
- but has no increase in number of species
What is Prezygotic (reproductive isolation)? - ANSWER-Impede mating between species or hinder
fertilization if mating is attempted
What is Postzygotic (reproductive isolation)? - ANSWER-If fertilization occurs, presents hybrids from
developing into a viable, fertile adult
What are some prezygotic barriers? - ANSWER-Habitat isolation - two species live in different habitats (in
the same area) and rarely meet (spider tree and trunk spiders )
Behavioral Isolation - species do no recognize signals or mating cues of other species (spiders, dancing vs
drumming)
Temporal Isolation - species breed at different times (times of day, seasons)
Mechanical Isolation - species are anatomically incompatible
, 4|Page
Gametic Isolation - species gametes are incompatible
What are the postzygotic barriers? - ANSWER-Reduced hybrid viability - hybrids fail to develop or reach
sexual maturity, hybrids are mostly or completely sterile, hybrid breakdown - offspring of hybrids have
reduced viability or fertility
What are the different models of speciation? - ANSWER-Allopatric - Geographically isolated groups--
>become reproductively isolated
Sympatric - Genetic or behavioral patterns while living in same area
Parapatric - pop. Spread over large area, but individuals mate with closest geographic neighbor--
>reduces gene flow and varying selection pressures
What is Coevolution? - ANSWER-An adaption in one species may lead to the evolution of an adaptation
in a species it interacts with
What is convergent evolution? - ANSWER-Independently evolved traits subjected to similar selection
pressures may become superficially similar
- Similar traits generated by convergent evolution are called homoplastic traits or homoplasies
What is a monophyletic group? - ANSWER-Graph that includes the common ancestor and all of its
descendents
What is a paraphyletic group? - ANSWER-Graph that includes the common ancestor and some but not all
of its descendants
What is a polyphyletic group? - ANSWER-Graph that does not include the common ancestor
What is a synapomorphies? - ANSWER-Shared derived characters
What is Parsimony? - ANSWER-Choosing the hypothesis that has the lowest number of changes
