2. Regular lawn mowing selects for short-headed rather than tall-headed dandelions because 
A. Tall flowers spread their seeds farther
B. Tall flowers are cut before they can produce seeds
C. Short flowers can reproduce
D. Short flowers spread their seeds farther
E. Short flowers have less competition when the lawn is mowed often

3. Cheetahs can run extremely fast because  
A.  They need to outrun lions
B.  Their ancestors who were able to run fast had an advantage and passed those genes on to their offsprings
C.  Over time, they gradually built up speed as they adapted to faster and faster prey species
D.  They are competing with stronger lions and hyenas for their food, so they need to be fast
E.  All of the options above

4. Tolerance limits are _______ that limit a species' survival. 
A. Temperature ranges
B. Any environmental conditions
C. Population sizes
D. Narrow salinity levels
E. Undesirable toxin concentrations

5. There are usually many tolerance limits responsible for limiting the number and location of a species. However, some organisms have ____________ that limit/limits their distribution.  
A.  a specific critical factor
B.  other environmental conditions
C.  many factors
D.  nothing

6. A species can withstand a wide range of pH as an adult but the juveniles can only withstand a narrow range of pH. The abiotic factor, pH, would best be described as a 
A. Stress factor
B. Intolerance factor
C. Tolerance limit
D. Critical factor
E. Physical factor

7. Which of the following fish species would be the best indicator of clean, well-oxygenated water? 
A. Carp
B. Largemouth bass
C. Catfish
D. Rainbow trout
E. Sunfish

8. Indicator species, such as lichens, generally have a(n) ___________ tolerance range for a ____________.  
A.  Narrow; critical factor
B.  Narrow; number of physical factors
C.  Average; number of physical factors
D.  Broad; number of critical factors
E.  Broad; critical factor

9. Use the following example:
A species can withstand a narrow range of temperature. Above 100F there are no species present. In the range from 97F to 100F and 90F to 94F there are a few species present. Below 90F there are no species present.
What would you label the range of temperature from 90F to 94F for this particular species? 
A. Zone of intolerance
B. Zone of physiological stress
C. Tolerance limit range
D. Optimal range
E. Range of tolerance

10. The most common reason that introduced species negatively impact an environment is because they  
A.  Are larger than native species
B.  Disrupt preexisting niches
C.  Are unusually efficient predators
D.  None of these is correct

11. Which of the following are pioneer species? 
A. Wood warblers
B. Dandelions
C. Starlings
D. Lichens
E. Humans

12. Primary succession occurs when a community develops ____________ while secondary succession occurs when one ________. 
A. Into a climax community; species replaces another
B. And replaces another; ecosystem becomes stable
C. On bare rock; biological community replaces another
D. And then fails; niche changes
E. Intraspecific competition; experiences interspecific competition

13. A climax community is one that  
A.  Is relatively stable and long lasting
B.  Lasts forever
C.  Contains oaks or white spruce
D.  Is impervious to disruption
E.  Is adapted to periodic disruption

14. In the coastal forest of Oregon an area was clear-cut for logging
In the coastal forest of Oregon an area was clear-cut for logging. Trees at the edge of the clearing and 200 meters into the forest died within a few months after the logging began. What is the best explanation for the death of the trees? 
A. The trees at the edge of the forest were more prone to disease
B. Increased sunlight, wind and temperature negatively affected the trees
C. The roots of all of the trees were damaged
D. Nitrogen fixing bacteria in the roots of the trees were killed

15. A community with hundreds of different types of primary producers, a few herbivores and only one carnivore, has 
A. Little complexity
B. Little diversity
C. A great deal of complexity
D. Low productivity
E. A great deal of productivity

16. Complexity in an ecological community has to do with the number of 
A. Species in the population
B. Species at each trophic level
C. Genetic variations within a species
D. Primary producers available
E. Primary producers relative to the number of consumers

17. In a biological community where diversity is great, such as a tropical rainforest, the abundance of any one species is likely to be 
A. Great
B. Small
C. Widely variable from year to year
D. The same from year to year
E. None of these, abundance does not depend on diversity

18. "Abundance" describes the total number of _________ while "diversity" describes the number of _________. 
A. Species in a community; individual organisms in a community
B. Organisms in a community; species in a community
C. Individuals in a niche; niches available to a given species
D. Species in a bioregion; trophic levels in a community
E. Biomes; habitats available for different species

19. A viceroy butterfly that closely resembles the bad tasting monarch is an example of __________, and the example of beetles that look like stinging wasps is an example of __________.  
A.  Batesian mimicry; Batesian mimicry
B.  Batesian mimicry; Muellerian mimicry
C.  Muellerian mimicry; Muellerian mimicry
D.  Muellerian mimicry; Batesian mimicry
E.  Commensalism; symbiosis

20. Predation influences evolution when 
A. Prey species develop defensive characteristics over generations
B. An individual predator adapts and becomes more efficient in catching its prey
C. Predators kill off all of their prey
D. A population of predators develop defensive characteristics
E. Prey species change their reproductive rate to match predation in the local ecosystem

21. Intraspecific competition is competition among ________ for resources.  
A.  Predators and prey
B.  Plants and animals
C.  Producers, consumers and detritivores
D.  Members of different species
E.  Members of a single species