Ecology (Test 1)
4. The following is a food web for a meadow habitat
that occupies 26.2km2. The primary producers’
biomass is uniformly distributed throughout the habitat
and totals 1,500 kg/km2.
Developers have
approved a project that
will permanently reduce
the primary producers’
biomass by 50% and remove all rabbits and deer.
Which of the following is the most likely result at the
completion of the project?
a. The biomass of the coyotes will be 6kg, and
the biomass of the hawks will be 0.5kg.
b. The biomass of coyotes will be dramatically
reduced.
c. The coyotes will switch prey preferences and
outcompete the hawks.
d. There will be 50% fewer voles and 90% fewer
hawks.
Ecology (Test 1)
6. The diagram below shows the progression of
ecological events after a fire in a particular
ecosystem. Based on the diagram, which of the
following best explains why the oak trees are later
replaced by other trees?
a. Eventually the other trees grow taller than the oak
trees and form a dense canopy that shades the
understory.
b. Oak trees alter the pH of the soil, making the
forest better suited for shrubs and other trees.
c. Roots of shrubs proliferate in the soil of the forest
ad prevent the oak trees from obtaining water.
d. Oak trees succumb to the environmental
pollutants more readily than do either the shrubs
or the other trees.
Ecology (Test 1)
21. In a hypothetical population of beetles, there is a wide variety
of color, matching the range of coloration of the tree trunks
on which the beetles hide from predators. The graphs below
illustrate four possible changes to the beetle population as a
result of a change in the environment due to pollution that
darkened the tree trunks.
Which of the following
includes the most likely
change in the coloration
of the beetle population
after pollution and a
correct rationale for the change?
a. The coloration range shifted toward more light-colored
beetles, as in diagram I. The pollution helped the
predators find the darkened tree trunks.
b. The coloration in the population split into 2 extremes, as
in diagram II. Both the lighter-colored and the darkercolored beetles were able to hide on the darker tree
trunks.
c. The coloration range became narrower, as in diagram III.
The predators selected beetles at the color extremes.
d. The coloration in the population shifted toward more
darker-colored beetles, as in diagram IV. The lightercolored beetles were found more easily by the predators
than were the darker colored beetles.
Ecology
(Test 1)
40.Figure 1 shows the growth of an algal species in a flask of
sterilized pond water. If phosphate is added as indicated, the
growth curve changes as shown in Figure II.
Which of the following is the best prediction of the algal growth
if nitrate is added instead of phosphate?
Ecology (Test 2)
11. Innate behaviors are genetically motivated
behaviors. Which of these is an innate behavior?
a. Altruism
b. Migration
c. Imprinting
d. Operant conditioning
Ecology (Test 2)
12. Which statement best describes pheromones?
a. Pheromones are chemicals emitted by an organism
that communicates information to other organisms in
the immediate area.
b. Pheromones are proteins that interact with sensory
receptors in the nose and mouth to elicit the desired
response.
c. Pheromones are proteins emitted by an organism that
communicate information to other organisms in the
area.
d. Pheromones are fast acting chemicals, often carried by
water that can affect the thoughts and responses of
another organism.
Ecology (Test 2)
13. Scouting bee behavior is important for the survival
of the entire hive and is an example of:
a.
b.
c.
d.
cooperative behavior
altruistic behavior
commensalism
mutualism
Ecology (Test 2)
16. Organisms respond to changes in their
environment through behavioral and physiological
mechanisms. Which of the following is an example
of this type of response?
a. Fixed action patterns in fish
b. Dominance hierarchies
c. Shivering and sweating in humans
d. Imprinting
Ecology (Test 2)
The world’s longest predator/prey study has been ongoing
on Isle Royale in Lake Superior. Isle Royale is one of our
nation’s beautiful National Parks. The world’s largest
freshwater lake has secluded the moose and wolf on this
island, and the study of their interactions and
interdependence has been ongoing since 1959. as a result
of this study of predators and their prey, and enormous
amount of data has been gathered and the populations of
moose have been studied at depth. With a moose
population that has reached a maximum of 2422 animals
and a minimum of 385 animals and a wolf population that
has reached a maximum of 50 animals and a minimum of
12 animals, there has been much speculation about how
the populations react to each other.
20. Some of the most recent data shoes a wolf population
of 21 animals (larger than average) and the moose
population of 385 animals (smaller than average). Which
of the following is an approximate prediction of the
immediate future populations of these animals?
a. The wolf and moose populations will neither increase nor
decrease because of the effects of climate change on this
isolated ecosystem.
b. The wolf population will decrease because of the lack of
prey while the moose population will grow because of the
increasing lack of predators.
c. The wolf population will decrease because of the availability
of prey while the moose population will decrease because of
the increase of predators.
d. Both the moose and wolf populations will increase because
of the interdependence in this isolated ecosystem.
21. During the mid 1970’s the population of moose on
Isle Royale dropped from 1500 to 850, and the
population of wolves dropped from 40 to 14. Which of
the following might be a factor in this significant
depression of populations?
a. Natural deviations in population size caused by factors
such as overpredation.
b. Decreased winter temperatures due to climate changes.
c. Human impact such as a forest fire depleting an essential
food source from the moose population causing starvation
of both species.
d. Genetic mutations in both populations due to these small
populations being “trapped” on this island and exhibiting
the founder effect.
22. The wolf population on Isle Royale has bloomed from
a small group of wolves that crossed an ice bridge during
the winter of 1950. Without the addition of more wolves
to this ecosystem the population has grown and shrunk
several times. What problem may the wolf population
face in this very isolated ecosystem?
a. Inbreeding will result in allelic frequencies that encourage
potentially harmful diseases.
b. A new species of wolf may develop due to the geographic
barriers presented to this population.
c. The lack of gene flow due to isolation may change allelic
frequencies compared to the general population.
d. The population may be unable to respond to changes in
the environment because of the lack of genetic diversity in
the population.