AP Biology Ecology Questions Name _______________________________
Directions: Answer the following questions from a past AP Biology Exam. Show your work for calculations and fill in
the answer blank for multiple choice questions.
123. To estimate the size of an animal population, researchers often use a method known as mark-recapture,
which involves marking individuals from a large population for easy identification upon recapture. The mark-recapture
method assumes that the proportion of marked individuals in the recapture group is equal to the proportion of marked
individuals in the entire population. Researchers used the mark-recapture method to estimate the number of individuals in
a population. Using the results presented in the table below, estimate the total number of individuals in the population.
Give your answer to the nearest whole number.
Number of Total
Marked Number of
Individuals Individuals
Recapture group 14 88
Entire population 180 ?
Show your calculations: Answer _______________________
8. A researcher is investigating the relationship between the existing species diversity in a community and the
ability of an introduced nonnative species to destabilize the community. Which of the following graphs is most
consistent with the claim that communities with high diversity are more resistant to change than are
communities with low diversity?
A) B)
C) D)
Answer: _______________
Questions 10-13
The figures below show the changes in populations of two species of flour beetles, Tribolium confusum (Figure I)
and Tribolium castaneum (Figure II), in cultures without parasites (○ ) and in cultures infected with a parasite (●).
Each data point represents the mean population size from ten culture dishes of equal size and food content.
10. Under which of the following conditions is
the observed number of beetles per culture dish 12. In Figure I, the difference between the two curves
the greatest? can best be attributed to which of the following?
(A) T. confusum with parasite at 500 days (A) The difference between controlled laboratory
(B) T. confusum without parasite at 300 days conditions and the natural environment
(C) T. castaneum with parasite at 100 days (B) The effect of the host on its parasite
(D) T. castaneum with parasite at 600 days (C) The influence of competition for limited
resources
11. The data over the duration of the experiment
(D) The natural variation among populations
provide the strongest support for which of the
following conclusions regarding the effect of the
13. If the experiment was continued for an additional
parasite on Tribolium populations?
500 days, the population density of T. castaneum
(A) T. confusum is adversely affected by the
with the parasite would most likely stabilize at a
parasite, while T. castaneum is not.
value closest to which of the following?
(B) T. castaneum is adversely affected by the
(A) 5 beetles/culture dish
parasite, while T. confusum is not.
(B) 10 beetles/culture dish
(C) Both T. confusum and T. castaneum are
(C) 20 beetles/culture dish
adversely affected by the parasite.
(D) 25 beetles/culture dish
(D) Both T. confusum and T. castaneum show increased
fitness in the presence of the parasite. Answers: _____________________
14. Beaked whales feed at various depths, but they defecate at the ocean’s surface. Nitrogen-rich whale
feces deposited in surface waters supply nutrients for algae that are eaten by surface dwelling fish. Which
of the following best predicts what would happen if the whale population decreased?
(A) There would be a reduction in surface nitrogen concentration, which would cause an algal
bloom.
(B) The surface fish populations would decline due to reduced populations of algae.
(C) The remaining whales would accumulate mutations at a faster rate.
(D) The remaining whales would be forced to forage in the deepest parts of the ocean.
Answer: _______________
37. In the Arctic Ocean, the predominant primary
producers are phytoplankton. Phytoplankton are
consumed by zooplankton, which in turn are eaten by
codfish. In years when there is more open water (less
ice coverage), there are more zooplankton and fish
than in years with less open water (more ice
coverage). Based on the graph above, the difference
is most likely because
(A) when there is less open water, light is blocked
from the zooplankton, so they cannot
produce as much food for the fish
(B) when there is more open water, the
temperature is warmer, so the zooplankton
and fish populations increase in size
(C) the ice blocks the light, so in years with more ice coverage, there is less photosynthesis by the
phytoplankton
(D) the ice increases the light available for
photosynthesis, so primary production increases and zooplankton populations increase in size
Answer: _______________________
47. Students in a class measured the mass of various living organisms. They then kept the organisms in
the dark for 24 hours before re-measuring them. None of the organisms were provided with nutrients
during the 24-hour period. The data are as follows.
Organism Starting Mass (g) Final Mass (g)
Elodea (submerged 15.10 14.01
aquatic plant)
Goldfish 10.10 9.84
Sea anemone 25.60 24.98
Which of the following is the best explanation for the pattern of change in mass of the organisms over
time?
(A) Water loss due to evaporation
(B) Cellular respiration
(C) The law of conservation of matter
(D) Growth and reproduction
Answer: ________________
122. Based on the data shown, calculate the average rate of increase in oxygen consumption for animals
acclimated to 5oC as the temperature increases from 10°C to 30°C. Give the answer in mL O 2/g/h/°C to
the nearest tenth.
Answer: _______________________
Show your calculations:
Free Response Questions:
You should be able to answer the types of questions proposed below:
3. As part of a new development, a concert venue consisting of a stage, bleacher area and open grassy
areas for sitting, and parking areas is constructed in a formerly wooded area.
(a) Predict ONE ecological consequence on the local plant community that is likely to result
during the preparation and construction of the venue. Justify your prediction.
(b) To maintain the grassy area, large quantities of water and chemicals are applied regularly.
Predict ONE effect on the local animal community that might result from regular use and
maintenance of the grassy area. Justify your prediction.
5. Genetically modified crops have been developed that produce a protein that acts as an insecticide that
makes the plants resistant to pests. Other genetic modifications make the crops more resistant to
herbicides that otherwise would kill the plants.
(a) Describe TWO potential biological risks of a large-scale cultivation and use of such
Genetically modified plants.
(b) For each of the risks you described in part (a), propose a practical approach for reducing
the risk.
