AP BIO MULTIPLE CHOICE EXAM 2025
QUESTIONS AND ANSWERS
All of the populations of organisms within a given area make up a
A. ecosystem
B. community
C. trophic level
D. biosphere
E. genus - ANS B
What is one reason for an even distribution pattern among a particular species in a community?
A. The species forms hierarchal social groups.
B. The species is breeding.
C. Resources are not limiting.
D. Members of the species mate for life.
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,E. The species is territorial. - ANS E
Which does not describe patterns of population growth?
A. Populations can 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 not vary sporadically in response to environmental changes.
E. Population size is not affected by other populations. - ANS E
The intrinsic growth rate of a population
A. is the number of yearly births in a population.
B. is the number of yearly births minus the number of yearly deaths in a population.
C. is the minimum number of births likely to occur in a population under ideal circumstances.
D. is the maximum potential for growth in a population under ideal conditions.
E. is the maximum potential for growth in a population given limited resources. - ANS D
Which factor is not typically density-dependent in an animal population?
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,A. nesting sites
B. food
C. water
D. shelter from cold
E. severe storms - ANS E
An exotic species is one which (??) an ecosystem.
A. is rare in
B. is foreign to
C. does not interact with the other species in
D. is the most dominant species in
E. destroys - ANS B
Which does not cause rapid growth in a population?
A. elimination of a pollutant
B. elimination of predators
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, C. increase in food supply
D. introduction of a new parasite
E. introduction into a new habitat - ANS D
During a single Oregon winter, minimum temperatures did not get much below freezing. The
following summer, large mosquito populations were observed in ponds. Cold weather came
early the next winter and most ponds froze for 3 months. The following summer, very low
mosquito populations were observed. What best explains this pattern in the mosquito
population?
A. a density independent factor
B. a density dependent factor
C. the ecosystem's carrying capacity
D. a limiting resource
E. global warming - ANS A
A laboratory experiment followed the growth of a flour beetle population over time. At first the
population increased dramatically but later growth slowed and the population size leveled off.
While food (the wheat flour in which they live) was abundant, the flour beetles began to eat
their own eggs when densities got high. What might we hypothesize about this behavior in the
four beetles?
A. It has no effect on the growth of the population, because food scarcity is the limiting factor.
B. It is intended to change the carrying capacity of the environment.
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QUESTIONS AND ANSWERS
All of the populations of organisms within a given area make up a
A. ecosystem
B. community
C. trophic level
D. biosphere
E. genus - ANS B
What is one reason for an even distribution pattern among a particular species in a community?
A. The species forms hierarchal social groups.
B. The species is breeding.
C. Resources are not limiting.
D. Members of the species mate for life.
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,E. The species is territorial. - ANS E
Which does not describe patterns of population growth?
A. Populations can 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 not vary sporadically in response to environmental changes.
E. Population size is not affected by other populations. - ANS E
The intrinsic growth rate of a population
A. is the number of yearly births in a population.
B. is the number of yearly births minus the number of yearly deaths in a population.
C. is the minimum number of births likely to occur in a population under ideal circumstances.
D. is the maximum potential for growth in a population under ideal conditions.
E. is the maximum potential for growth in a population given limited resources. - ANS D
Which factor is not typically density-dependent in an animal population?
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,A. nesting sites
B. food
C. water
D. shelter from cold
E. severe storms - ANS E
An exotic species is one which (??) an ecosystem.
A. is rare in
B. is foreign to
C. does not interact with the other species in
D. is the most dominant species in
E. destroys - ANS B
Which does not cause rapid growth in a population?
A. elimination of a pollutant
B. elimination of predators
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, C. increase in food supply
D. introduction of a new parasite
E. introduction into a new habitat - ANS D
During a single Oregon winter, minimum temperatures did not get much below freezing. The
following summer, large mosquito populations were observed in ponds. Cold weather came
early the next winter and most ponds froze for 3 months. The following summer, very low
mosquito populations were observed. What best explains this pattern in the mosquito
population?
A. a density independent factor
B. a density dependent factor
C. the ecosystem's carrying capacity
D. a limiting resource
E. global warming - ANS A
A laboratory experiment followed the growth of a flour beetle population over time. At first the
population increased dramatically but later growth slowed and the population size leveled off.
While food (the wheat flour in which they live) was abundant, the flour beetles began to eat
their own eggs when densities got high. What might we hypothesize about this behavior in the
four beetles?
A. It has no effect on the growth of the population, because food scarcity is the limiting factor.
B. It is intended to change the carrying capacity of the environment.
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