OFFICIAL BIOLOGY CLEP TEST -
COLLEGE BOARD EXAM 2025
QUESTIONS AND ANSWERS
In which of the following ways do social insects
benefit most from having several types or castes
within the species?
(A) Each colony is able to include a large number of individuals.
(B) The secretions or odors produced by the protective caste are an effective defense.
(C) The division of the species into castes ensures the survival of the fittest.
(D) Large numbers of the worker caste can migrate to start new colonies.
(E) The specialized structure of each caste permits division of labor and greater
efficiency. - ANS (E)The division of the species into castes ensures the survival of the fittest
2. The greatest diversity of structure and of methods of locomotion is exhibited in the
individuals of
(A) a class
(B) a family
(C) an order
(D) a species
(E) a phylum - ANS (E) a phylum
3. Of the following, which is an example of a
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,mutualistic relationship?
(A) The protozoan Trichonympha digesting wood in the gut of a termite
(B) The sporozoan Plasmodium reproducing in human blood cells and liberating toxins into
the human body
(C) Two species of Paramecium deriving food from a common Laboratory culture
(D) Rabbits being eaten by foxes
(E) Humans inadvertently providing food for cockroaches - ANS (A) The protozoan
Trichonympha digesting wood in the gut of a termite
4. Evidence that multicellular green plants may
have evolved from green algae is best supported
by the fact that in both
(A) the gametophyte generation is dominant
(B) the sporophyte generation is dominant
(C) chlorophylls a and b are photosynthetic pigments
(D) xylem vessels are pitted and spiraled
(E) male gametes are nonflagellated - ANS (C) chlorophylls a and b are photosynthetic
pigments
5. All of the following statements concerning the
light-capturing reactions of photosynthesis are
true EXCEPT
(A) An initial event is the excitation of electrons
in chlorophyll by light energy.
(B) The excited electrons are raised to a higher
energy level.
(C) If not captured, the excited electrons drop
back to their initial energy levels.
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,(D) If captured, some of the energy of the excited electrons is used to split carbon dioxide into
carbon and oxygen.
(E) Light is absorbed by pigments that are embedded in membranes. - ANS (D) If captured,
some of the energy of the excited electrons is used to split carbon dioxide into carbon and
oxygen.
6. Which of the following statements best explains
the hypothesis that the development of sexual
reproduction has resulted in acceleration of the
rate of evolution?
(A) Mutations are more likely to occur in spermatogenesis and oogenesis than in mitotically
dividing cells.
(B) Sexual reproduction results in more
offspring than does asexual reproduction.
(C) Those members of a species that are best
adapted to their environment are most likely to be successful in sexual reproduction.
(D) Mutations usually do not occur in the
production of spores or in cells dividing by
fission.
(E) Sexual reproduction is more likely to result
in genetic recombination than is asexual
reproduction. - ANS (E) Sexual reproduction is more likely to result
in genetic recombination than is asexual
reproduction.
7. A frog skeletal muscle contracts in response to
an electrical stimulus. Increase of the stimulus
intensity by 50 percent will increase the strength
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, of response nearly 50 percent. If the intensity is
again increased 50 percent, the response will
increase only about another 25 percent. Further
increase in the stimulus intensity produces no
further increase in response.
The observations above are best explained by
which of the following?
(A) A muscle functions with an all-or-none
mechanism.
(B) Muscle-fiber sarcolemma is electrically
resistant.
(C) The fibers of a muscle do not all contract at
the same rate.
(D) The fibers of a muscle fatigue at varying rates.
(E) The fibers of a muscle have varying thresholds for response. - ANS (E) The fibers of a
muscle have varying thresholds for response
8. Nitrogen-containing waste products are excreted
as the result of the metabolism of which of the
following?
(A) Proteins
(B) Fats
(C) Simple sugars
(D) Starch
(E) Cellulose - ANS (A) Proteins
9. Deposits of coal in Greenland and the Antarctic
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COLLEGE BOARD EXAM 2025
QUESTIONS AND ANSWERS
In which of the following ways do social insects
benefit most from having several types or castes
within the species?
(A) Each colony is able to include a large number of individuals.
(B) The secretions or odors produced by the protective caste are an effective defense.
(C) The division of the species into castes ensures the survival of the fittest.
(D) Large numbers of the worker caste can migrate to start new colonies.
(E) The specialized structure of each caste permits division of labor and greater
efficiency. - ANS (E)The division of the species into castes ensures the survival of the fittest
2. The greatest diversity of structure and of methods of locomotion is exhibited in the
individuals of
(A) a class
(B) a family
(C) an order
(D) a species
(E) a phylum - ANS (E) a phylum
3. Of the following, which is an example of a
1 Copyright ©2025 BRAINBARTER ALL RIGHTS RESERVED
,mutualistic relationship?
(A) The protozoan Trichonympha digesting wood in the gut of a termite
(B) The sporozoan Plasmodium reproducing in human blood cells and liberating toxins into
the human body
(C) Two species of Paramecium deriving food from a common Laboratory culture
(D) Rabbits being eaten by foxes
(E) Humans inadvertently providing food for cockroaches - ANS (A) The protozoan
Trichonympha digesting wood in the gut of a termite
4. Evidence that multicellular green plants may
have evolved from green algae is best supported
by the fact that in both
(A) the gametophyte generation is dominant
(B) the sporophyte generation is dominant
(C) chlorophylls a and b are photosynthetic pigments
(D) xylem vessels are pitted and spiraled
(E) male gametes are nonflagellated - ANS (C) chlorophylls a and b are photosynthetic
pigments
5. All of the following statements concerning the
light-capturing reactions of photosynthesis are
true EXCEPT
(A) An initial event is the excitation of electrons
in chlorophyll by light energy.
(B) The excited electrons are raised to a higher
energy level.
(C) If not captured, the excited electrons drop
back to their initial energy levels.
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,(D) If captured, some of the energy of the excited electrons is used to split carbon dioxide into
carbon and oxygen.
(E) Light is absorbed by pigments that are embedded in membranes. - ANS (D) If captured,
some of the energy of the excited electrons is used to split carbon dioxide into carbon and
oxygen.
6. Which of the following statements best explains
the hypothesis that the development of sexual
reproduction has resulted in acceleration of the
rate of evolution?
(A) Mutations are more likely to occur in spermatogenesis and oogenesis than in mitotically
dividing cells.
(B) Sexual reproduction results in more
offspring than does asexual reproduction.
(C) Those members of a species that are best
adapted to their environment are most likely to be successful in sexual reproduction.
(D) Mutations usually do not occur in the
production of spores or in cells dividing by
fission.
(E) Sexual reproduction is more likely to result
in genetic recombination than is asexual
reproduction. - ANS (E) Sexual reproduction is more likely to result
in genetic recombination than is asexual
reproduction.
7. A frog skeletal muscle contracts in response to
an electrical stimulus. Increase of the stimulus
intensity by 50 percent will increase the strength
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, of response nearly 50 percent. If the intensity is
again increased 50 percent, the response will
increase only about another 25 percent. Further
increase in the stimulus intensity produces no
further increase in response.
The observations above are best explained by
which of the following?
(A) A muscle functions with an all-or-none
mechanism.
(B) Muscle-fiber sarcolemma is electrically
resistant.
(C) The fibers of a muscle do not all contract at
the same rate.
(D) The fibers of a muscle fatigue at varying rates.
(E) The fibers of a muscle have varying thresholds for response. - ANS (E) The fibers of a
muscle have varying thresholds for response
8. Nitrogen-containing waste products are excreted
as the result of the metabolism of which of the
following?
(A) Proteins
(B) Fats
(C) Simple sugars
(D) Starch
(E) Cellulose - ANS (A) Proteins
9. Deposits of coal in Greenland and the Antarctic
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