ASU BIO 182 EXAM 2- COMPLETE QUESTIONS AND
DETAILED SOLUTIONS LATEST UPDATE THIS YEAR
JUST RELEASED
Question 1: 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
Question 2: Does natural selection lead to even greater
complexity?
Answer:
Evolution is a non-directional process
Question 3: 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
Question 4: 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
Question 5: What is the genealogical concept?
Answer:
,• defines a species as a set of organisms with a unique genetic history
Question 6: What is the morphological species concept?
Answer:
defines a species in terms of its unique structural features (its
morphology)
Question 7: 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
Question 8: 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
Question 9: 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
,Question 10: 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
Question 11: What is the key to speciation?
Answer:
Reproductive isolation
- even w/o geographic isolation
Question 12: What is sympatric speciation?
Answer:
When populations are in the same physical area
•But become genetically isolated by genetic events
• e.g., polyploidy
•Or behavioral or other isolating mechanisms • e.g., mating patterns,
feeding behavior
Question 13: 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
Question 14: What are the types of reproductive isolation?
Answer:
Prezygotic and Postzygotic
Question 15: What is Prezygotic (reproductive isolation)?
, Answer:
Impede mating between species or hinder fertilization if mating is
attempted
Question 16: What is Postzygotic (reproductive isolation)?
Answer:
If fertilization occurs, presents hybrids from developing into a viable,
fertile adult
Question 17: 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
Gametic Isolation - species gametes are incompatible
Question 18: 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
Question 19: 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
DETAILED SOLUTIONS LATEST UPDATE THIS YEAR
JUST RELEASED
Question 1: 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
Question 2: Does natural selection lead to even greater
complexity?
Answer:
Evolution is a non-directional process
Question 3: 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
Question 4: 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
Question 5: What is the genealogical concept?
Answer:
,• defines a species as a set of organisms with a unique genetic history
Question 6: What is the morphological species concept?
Answer:
defines a species in terms of its unique structural features (its
morphology)
Question 7: 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
Question 8: 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
Question 9: 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
,Question 10: 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
Question 11: What is the key to speciation?
Answer:
Reproductive isolation
- even w/o geographic isolation
Question 12: What is sympatric speciation?
Answer:
When populations are in the same physical area
•But become genetically isolated by genetic events
• e.g., polyploidy
•Or behavioral or other isolating mechanisms • e.g., mating patterns,
feeding behavior
Question 13: 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
Question 14: What are the types of reproductive isolation?
Answer:
Prezygotic and Postzygotic
Question 15: What is Prezygotic (reproductive isolation)?
, Answer:
Impede mating between species or hinder fertilization if mating is
attempted
Question 16: What is Postzygotic (reproductive isolation)?
Answer:
If fertilization occurs, presents hybrids from developing into a viable,
fertile adult
Question 17: 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
Gametic Isolation - species gametes are incompatible
Question 18: 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
Question 19: 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
