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Chapter 5 & 6 Practice



Multiple Choice
Identify the choice that best completes the statement or answers the question.
 

 1. 

What is most significant when determining the diversity of an ecosystem?
a.
The number of organisms present
b.
The number of species present
c.
The amount of land the ecosystem covers
d.
The amount of precipitation an ecosystem receives
e.
The interactions between producers and consumers
 
 
Figure 5-2

nar001-1.jpg
 

 2. 

Use Figure 5-2. The diagram shown is known as a:
a.
Branching diagram
b.
Phylogenetic tree
c.
Evolutionary diagram
d.
Ancestral trace
e.
Species evolutionary tree
 

 3. 

Use Figure 5-2. Based on the diagram, which structure would be considered the most primitive?
a.
Notochord
b.
Vertebrae
c.
Hinged jaw
d.
4 legs
e.
Mammary glands
 

 4. 

If a bird that normally has green feathers produces offspring with blue, this is most likely the result of:
a.
A genetic mutation
b.
Evolution
c.
Natural selection
d.
Natural variation
e.
Genotypic variation
 

 5. 

When part of one chromosome breaks off and reattaches to another chromosome, this is known as:
a.
A mutation
b.
Reattachment disorder
c.
Natural selection
d.
Recombination
e.
Genetic merging
 

 6. 

Which of the following are processes in which evolution occurs?
I. Artificial selection
II. Natural selection
III. Genetic Drift
a.
I only
b.
II only
c.
III only
d.
II and III
e.
I, II, and III
 

 7. 

Which two scientists are credited with developing the theory of evolution by natural selection?
a.
Watson and Crick
b.
Darwin and Wallace
c.
Mendel and Darwin
d.
Shannon and Simpson
e.
Muir and Carson
 

 8. 

Which of the following does not contribute to the increase in biodiversity of an ecosystem?
a.
Habitat loss
b.
Evolution
c.
Founder effect
d.
Intermediate disturbances
e.
Natural selection
 

 9. 

A population of rabbits with typical variations of traits lives in a meadow with a depression that runs through the middle. Over time, the depression fills in with water and becomes a river, separating the one population into two over a period of several years.  This is an example of:
a.
Artificial selection
b.
Mutation
c.
Sympatric speciation
d.
Bottleneck effect
e.
Allopatric speciation
 

 10. 

Which of the following is not an example of geographic isolation?
a.
Founder effect
b.
Natural disturbance that separates a population into two
c.
Allopatric speciation
d.
Sympatric speciation
e.
A group of birds colonizes a new island
 

 11. 

If allopatric speciation has occurred after a population has split into two distinct populations, what is the most likely result if the two species were reunited after many generations?
a.
The two populations would not be able to interbreed
b.
The two populations would be able to breed, producing fertile offspring
c.
Individuals that shared similar phenotypes would be able breed
d.
The two new populations would become polyploids
e.
The two new populations would go through a series of mutations to become more similar
 

 12. 

Under what conditions would sympatric speciation most likely occur?
a.
Geographic isolation
b.
Bottleneck effect
c.
Founder effect
d.
Polyploidy
e.
Genetic drift
 

 13. 

Which of the following would result in the highest rate of evolution?
a.
A rapidly changing environment
b.
A population with high genetic variation
c.
A long generation time
d.
Few variations of phenotypes and genotypes
e.
Drastic changes to the environment
 
 
Figure 5-3
nar002-1.jpg
 

 14. 

Use Figure 5-3. How would you classify species 2?
a.
Niche generalist
b.
Niche specialist
c.
Vulnerable to extinction
d.
Specialized species
e.
Vulnerable to environmental change
 

 15. 

Approximately what percentage of species that have lived on the planet is now thought to be extinct?
a.
10%
b.
33%
c.
50%
d.
85%
e.
99%
 
 
Figure 5-5

nar003-1.jpg
 

 16. 

Use Figure 5-5. Based on the fossils found at each level in the diagram, which of the following conclusions would be most valid?
a.
The area changed from land to swamp to ocean
b.
There was a rise in sea level
c.
The area was primarily swamp land
d.
There was a decrease in sea level
e.
The area has always been covered by water
 

 17. 

How would a collision with a meteorite lead to a worldwide, mass extinction?
a.
A large meteorite would produce a dust cloud that blocked sunlight, reducing photosynthesis
b.
A large meteorite would crush a large number of organisms, reducing population sizes
c.
A large meteorite would destroy a large area of habitat, reducing population sizes
d.
The collision would increase global temperatures rapidly and populations would not be able to adapt
e.
A large meteorite would produce a large dust cloud, reducing overall air quality
 

 18. 

Which of the following is not considered to be contributing to the current increase in extinction rates?
a.
Habitat destruction
b.
Natural selection
c.
Overharvesting
d.
Introduction of invasive species
e.
Climate change
 
 
Figure 5-6

nar004-1.jpg
 

 19. 

Use Figure 5-6. Which of the communities listed has the highest species evenness?
a.
Community 1
b.
Community 2
c.
Community 3
d.
Community 4
e.
Both Communities 3 and 4
 

 20. 

Use Figure 5-6. Which of the communities listed most clearly represents a community with low species evenness?
a.
Community 1
b.
Community 2
c.
Community 3
d.
Community 4
e.
All communities show relatively equal evenness
 

 21. 

Use Figure 5-6. Which of the communities listed would be least vulnerable to the effects of environmental disturbances?
a.
Community 1
b.
Community 2
c.
Community 3
d.
Community 4
e.
All communities are equally vulnerable
 

 22. 

Which of the following decreases genetic variation?
I. Bottleneck effect
II. Mutation
III. Genetic drift
a.
I
b.
II
c.
I and III
d.
II and III
e.
I, II, and III
 

 23. 

The organisms that represent all of the different interacting species within an ecosystem make up a
a.
population
b.
community
c.
trophic level
d.
biosphere
e.
Genus
 

 24. 

Which type of population distribution can enhance protection from predators?
a.
Random distribution
b.
Uniform distribution
c.
Clumped distribution
d.
Both a and c
e.
None of the above are correct.
 

 25. 

Which of the following is true?
a.
Some populations grow without restraint as long as resources are not limiting.
b.
The size of some populations tends to remain relatively constant over time.
c.
In some populations size fluctuates in a cyclical pattern.
d.
Population size may vary sporadically in response to environmental changes.
e.
All of the above are true.
 

 26. 

At the start of a study there were 200 spotted salamanders in an old-growth forest patch in western Oregon.  Over the next year a biologist tracking the salamanders saw that 25 new salamanders hatched and 5 died.  Thus r for this year was _____.
a.
0.1
b.
5
c.
20
d.
25
e.
200
 

 27. 

The intrinsic growth rate of a population
a.
directly affects environmental resistance.
b.
causes changes in birth rates without affecting death rates.
c.
causes changes in death rates without affecting birth rates.
d.
is the maximum rate at which a population may increase.
e.
all of the above
 

 28. 

A population of rabbits, introduced to an island, has rapid growth for a few years; then its growth slows.  The population becomes stable because
a.
the carrying capacity has been reached.
b.
environmental  resistance declines.
c.
immigration is reduced.
d.
r declines.
e.
Bergman’s Principle takes effect.
 

 29. 

Rapid growth may be temporarily be observed in a population in response to all of these EXCEPT
a.
elimination of a pollutant.
b.
elimination of predators.
c.
increase in food supply.
d.
introduction of a new parasite.
e.
introduction into a new habitat.
 

 30. 

During the winter of 1999, minimum temperatures did not get much below freezing in an Oregon pond, and the following summer large mosquito populations were observed.  In the winter of 2000, frost came early, and most ponds froze for 3 months.  In the following summer, very low mosquito populations were observed.  This is an example of
a.
density-independent regulation.
b.
density-dependent regulation.
c.
ecosystem carrying capacity.
d.
community carrying capacity.
e.
exotic regulation
 

 31. 

An important density-independent factor limiting population size is _____.
a.
predation
b.
weather
c.
environmental resistance
d.
competition
e.
food quantity
 

 32. 

The classic study of the number of lynx and snowshoe hares purchased from trappers by the Hudson Bay Company in northern Canada between 1845 and 1935 showed dramatic, closely linked population cycles of these predators and their prey.  But this was not a carefully controlled scientific study.  The results of this study could have been skewed because
a.
there was no control study to show whether the number of hares fluctuated even in the absence of lynx.
b.
there may have been other predators for hares in the ecosystem other than lynx.
c.
lynx might eat other small prey.
d.
weather and other environmental conditions might have affected pelt collection.
e.
all of the above
 

 33. 

A study conducted in the laboratory used wasps as predators and bean weevils as prey.  The wasps lay their eggs on weevil larvae, which provide food for the newly hatched wasps.  What would be the most likely hypothesis for the outcome of this experiment?
a.
The prey population increased and decreased slightly later than the predator population.
b.
The predator population increased and decreased slightly later than the prey population.
c.
The two populations fluctuated synchronously.
d.
The two populations fluctuated asynchronously
e.
There was no correlation between the fluctuations in the two populations.
 

 34. 

Which of the following is a density-independent event that could limit the size of a population?
a.
a mild winter, which reduces death rates
b.
the accidental spill of a pesticide that causes the population to decrease
c.
an increase in a predator population
d.
the reduction of a competitor species
e.
an outbreak of a parasite that spreads through close contact
 

 35. 

If you were studying the niche of a species of bird, you might study
a.
the food it eats.
b.
its predators.
c.
the temperatures it needs to survive.
d.
the places where it builds its nests.
e.
all of the above
 

 36. 

Two species that have a high degree of niche overlap will
a.
compete intensely.
b.
speciate.
c.
interbreed.
d.
be a predator-prey pair.
e.
coexist peacefully.
 

 37. 

If similar species each occupy a smaller niche when they live together than they would if they lived alone, they are said to be
a.
involved in succession.
b.
partitioning resources.
c.
coevolving.
d.
increasing niche overlap.
e.
engaging in mimicry.
 

 38. 

Scientists visiting a remote island find two species of birds that appear nearly identical except for bill size.  The species with the larger bill eats large seeds, and the species with the smaller bill eats small seeds.  According to genetic evidence, the two species are extremely closely related to each other.  Which of the following is the most likely explanation of the different bill sizes in these species?
a.
Convergent Evolution has led to similar genetic fingerprints
b.
natural and random variability between species
c.
competition between the two species resulted in resource partitioning
d.
mutations resulted in an inferior species with small, defective bills
e.
the two species recently arrived on the island from distant continents, where their bill sizes had previously evolved in response to the types of foods they ate in their native lands.
 

 39. 

Earthworms live in many grass and forest ecosystems, and aerate soil as they burrow.  They ingest organic matter and travel between soil horizons.  These traits, taken collectively, refer to the _____ of the earthworm.
a.
niche
b.
habitat
c.
community profile
d.
ecosystem profile
e.
resource partition profile
 

 40. 

Two species of buttercup can be found in the same field in South Dakota.  They emerge at different times: one species emerges and flowers in early spring, and the other species emerges in late summer, after the first species has set seed. Both flower species are pollinated by the same insect species, which is common in spring and summer.  The different flowering times are likely due to
a.
competitive exclusion.
b.
niche fragmentation.
c.
niche realignment.
d.
resource partitioning.
e.
parasitism.
 

 41. 

Two species of aster can be found in a field in New York, and they tend to flower at the same approximate time in early spring.  When some ecology students decide to conduct an experiment in community dynamics, they selectively remove one species from the field by handpicking all plants of that species.  When the one species is removed, the other species shows a significant increase in its population the next season.  This study demonstrates
a.
competitive exclusion.
b.
niche fragmentation.
c.
niche realignment.
d.
resource partitioning.
e.
interspecific competition
 

 42. 

In his 1961 paper, “The Paradox of the Plankton,” ecologist G.E. Hutchinson noted that several species of algae coexist, sharing the same few mineral nutrient resources in homogeneous open water systems.  As there is little chance of resource partitioning and niche differentiation in such a situation, the paradox of their coexistence is an apparent violation of
a.
Darwin’s Theory of Evolution by means of Natural Selection.
b.
the Climax Theory of Succession.
c.
the Competitive Exclusion Principle.
d.
the Law of Mass Action.
e.
the Redfield Ratio.
 

 43. 

If you find a brightly colored insect resting on a leaf, it is most likely to be
a.
poisonous or distasteful.
b.
prey for birds.
c.
camouflaged.
d.
a parasite.
e.
a young insect.
 

 44. 

Which of these describes an effective means that prey species may use to evade predators?
a.
mimicry
b.
warning coloration
c.
chemical secretions
d.
camouflage
e.
all of the above
 

 45. 

Which of these might a predator use to better enable it to catch its prey?
a.
startle coloration
b.
warning coloration
c.
camouflage
d.
symbiosis
e.
coevolution
 

 46. 

Which behavioral response to the threat of predation is most likely to be selected for in a species that uses camouflage for protection?
a.
a quick escape response
b.
a sudden display to startle the predator
c.
a cooperative behavior
d.
a behavior that mimics the behavior of the predator
e.
a motionless behavior
 

 47. 

Which of the following is NOT an example of two organisms in a mutualistic relationship?
a.
humans and the protozoa that cause malaria
b.
flowering plants and their pollinators
c.
cows and the bacteria in their guts
d.
fungi and algae within a lichen
e.
nitrogen-fixing bacteria and legume plants
 

 48. 

What characteristic best distinguishes predators from parasites?
a.
Predators feed on large prey, whereas parasites feed on small prey.
b.
Parasites live on or within their prey.
c.
Predators kill their hosts immediately, whereas parasites usually do not.
d.
Parasites only attack primarily weakened or old organisms.
e.
Parasites never kill their prey.
 

 49. 

Sap-feeding insects that feed on plants may be classified as
a.
predators.
b.
parasites.
c.
hosts.
d.
commensalists.
e.
prey.
 

 50. 

_____ succession begins on bare rock after glaciers have passed, or on newly formed volcanic islands.
a.
Primary
b.
Secondary
c.
Climax
d.
Pioneer
e.
Not enough information to tell
 



 
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