PASSPOINT PRO SOUTHEASTERN LOUISIANA UNIVERSITY
GBIO 200
CELL BIOLOGY
EXAM 3 - 125Q
Cellular respiration, oxidative phosphorylation, cytoskeleton, cell
cycle, mitosis, meiosis, and apoptosis
125 A-D FULL
ORIGINAL QUESTIONS ANSWER CHOICES RATIONALES
Built for focused exam review
Concept recall + application questions
Immediate answers with concise explanations
Compact layout for fast review and printing
Original practice content aligned to GBIO 200 topics
PassPoint Pro | Practice. Understand. Perform. GBIO 200
,PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
HOW TO USE THIS PRACTICE SET
Format: Each item includes four answer choices followed immediately by the correct answer and an explanation. Best use:
Complete a first pass without reading the answer, then use each rationale to repair weak concepts. Coverage: Cellular
respiration, oxidative phosphorylation, cytoskeleton, cell cycle, mitosis, meiosis, and apoptosis.
QUESTIONS 1-25
1 Which term or structure best matches the following description: a cysteine protease that cleaves
specific substrates during apoptosis?
A. Bcl-2
B. cytochrome c release
C. apoptosis
D. caspase
Answer: D
Explanation: Caspase is correct because it is a cysteine protease that cleaves specific substrates during apoptosis. An inactive protease
becomes activated in a cascade and dismantles cellular proteins. This match is more specific than the related alternatives, which describe
different structures, molecules, or processes.
2 A student is reviewing p53. Which description is most accurate?
A. a regulatory protein whose concentration changes through the cell cycle and activates specific cyclin-dependent kinases
B. the cell-cycle period after DNA replication when cells prepare for mitosis and assess replicated DNA
C. a tumor-suppressor transcription factor activated by cellular stress or DNA damage that can promote arrest, repair, senescence,
or apoptosis
D. a protein kinase whose activity depends on binding a cyclin and that drives cell-cycle transitions by phosphorylating targets
Answer: C
Explanation: The correct description of p53 is that it is a tumor-suppressor transcription factor activated by cellular stress or DNA damage
that can promote arrest, repair, senescence, or apoptosis. DNA damage causes a cell to stop dividing and induce genes that help prevent
propagation of mutations. The other choices define different concepts and therefore do not fit this term.
3 A daughter cell increases in size and decides whether conditions are suitable for another division cycle.
What is the best explanation for the finding?
A. G2 phase
B. G1 phase
C. cyclin
D. Rb protein
Answer: B
Explanation: G1 phase best explains the observation because it is the cell-cycle period after mitosis when cells grow, perform functions,
and prepare for DNA replication. The scenario is a direct application of that function or mechanism. The distractors are related cell-biology
concepts but do not account for the key feature described.
Original practice questions with explanations Page 2
,PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
4 A cell undergoes the following change: Blocking it under anaerobic conditions would limit NAD+
regeneration and slow glycolysis. Which target was most likely altered?
A. fermentation
B. FADH2
C. NADH
D. pyruvate dehydrogenase complex
Answer: A
Explanation: Fermentation is the best match. It is a pathway that regenerates NAD+ from NADH when the respiratory chain cannot
oxidize NADH efficiently, so the stated consequence follows directly when its function is changed. The other options can influence cellular
behavior, but they do not most directly predict this specific outcome.
5 Which term-description pairing is correct?
A. oxygen - a compound or process that dissipates the proton gradient without producing ATP, allowing respiration to continue with
energy released as heat
B. electron transport chain - the terminal electron acceptor of the mitochondrial respiratory chain under aerobic conditions
C. uncoupler - a series of inner mitochondrial membrane complexes that transfer electrons and use released energy to pump
protons
D. ATP synthase - a rotary membrane enzyme that uses proton flow down an electrochemical gradient to drive ATP formation
Answer: D
Explanation: The correct pairing is ATP synthase with its defining feature: a rotary membrane enzyme that uses proton flow down an
electrochemical gradient to drive ATP formation. Protons return to the mitochondrial matrix through a protein complex that converts ADP
and phosphate into ATP. The remaining pairs intentionally mismatch a term with the description of a different concept.
6 Which option is most accurately defined as a specialized division program that reduces chromosome
number and increases genetic diversity in gamete-producing lineages?
A. metaphase checkpoint
B. meiosis
C. cohesin
D. kinesin
Answer: B
Explanation: Meiosis is correct because it is a specialized division program that reduces chromosome number and increases genetic
diversity in gamete-producing lineages. One diploid precursor ultimately generates haploid cells after two nuclear divisions. This match is
more specific than the related alternatives, which describe different structures, molecules, or processes.
7 Which statement best describes metaphase checkpoint?
A. a protein structure assembled on centromeric DNA that connects chromosomes to spindle microtubules
B. a surveillance mechanism that delays anaphase until chromosomes are properly attached to the spindle
C. a protease activated at anaphase onset that cleaves cohesin and permits sister chromatids to separate
D. physical division of the cytoplasm to produce separate daughter cells after nuclear division
Answer: B
Explanation: The correct description of metaphase checkpoint is that it is a surveillance mechanism that delays anaphase until
chromosomes are properly attached to the spindle. One kinetochore remains unattached, so sister chromatids are not yet allowed to
separate. The other choices define different concepts and therefore do not fit this term.
Original practice questions with explanations Page 3
, PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
8 Pyruvate enters mitochondria and is oxidatively decarboxylated before the citric acid cycle. Which
structure or process is most directly involved?
A. fermentation
B. pyruvate dehydrogenase complex
C. FADH2
D. glycolysis
Answer: B
Explanation: Pyruvate dehydrogenase complex best explains the observation because it is the mitochondrial enzyme complex that
converts pyruvate to acetyl-CoA while producing NADH and CO2. The scenario is a direct application of that function or mechanism. The
distractors are related cell-biology concepts but do not account for the key feature described.
9 A selective perturbation causes this outcome: Blocking DNA synthesis prevents normal completion of
this phase. Which process or structure is the best match?
A. Rb protein
B. cyclin
C. S phase
D. G1 phase
Answer: C
Explanation: S phase is the best match. It is the cell-cycle phase in which nuclear DNA is replicated, so the stated consequence follows
directly when its function is changed. The other options can influence cellular behavior, but they do not most directly predict this specific
outcome.
10 Which term-description pairing is correct?
A. cytokinesis - a protein structure assembled on centromeric DNA that connects chromosomes to spindle microtubules
B. cohesin - physical division of the cytoplasm to produce separate daughter cells after nuclear division
C. separase - a protease activated at anaphase onset that cleaves cohesin and permits sister chromatids to separate
D. kinetochore - a protein complex that holds replicated sister chromatids together until anaphase
Answer: C
Explanation: The correct pairing is separase with its defining feature: a protease activated at anaphase onset that cleaves cohesin and
permits sister chromatids to separate. A protease is released from inhibition just before chromatids move toward opposite spindle poles.
The remaining pairs intentionally mismatch a term with the description of a different concept.
11 Identify the concept described here: an anti-apoptotic protein family member that helps preserve
mitochondrial outer membrane integrity.
A. apoptosis
B. cytochrome c release
C. caspase
D. Bcl-2
Answer: D
Explanation: Bcl-2 is correct because it is an anti-apoptotic protein family member that helps preserve mitochondrial outer membrane
integrity. A survival protein prevents mitochondrial release of pro-apoptotic factors. This match is more specific than the related
alternatives, which describe different structures, molecules, or processes.
Original practice questions with explanations Page 4
GBIO 200
CELL BIOLOGY
EXAM 3 - 125Q
Cellular respiration, oxidative phosphorylation, cytoskeleton, cell
cycle, mitosis, meiosis, and apoptosis
125 A-D FULL
ORIGINAL QUESTIONS ANSWER CHOICES RATIONALES
Built for focused exam review
Concept recall + application questions
Immediate answers with concise explanations
Compact layout for fast review and printing
Original practice content aligned to GBIO 200 topics
PassPoint Pro | Practice. Understand. Perform. GBIO 200
,PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
HOW TO USE THIS PRACTICE SET
Format: Each item includes four answer choices followed immediately by the correct answer and an explanation. Best use:
Complete a first pass without reading the answer, then use each rationale to repair weak concepts. Coverage: Cellular
respiration, oxidative phosphorylation, cytoskeleton, cell cycle, mitosis, meiosis, and apoptosis.
QUESTIONS 1-25
1 Which term or structure best matches the following description: a cysteine protease that cleaves
specific substrates during apoptosis?
A. Bcl-2
B. cytochrome c release
C. apoptosis
D. caspase
Answer: D
Explanation: Caspase is correct because it is a cysteine protease that cleaves specific substrates during apoptosis. An inactive protease
becomes activated in a cascade and dismantles cellular proteins. This match is more specific than the related alternatives, which describe
different structures, molecules, or processes.
2 A student is reviewing p53. Which description is most accurate?
A. a regulatory protein whose concentration changes through the cell cycle and activates specific cyclin-dependent kinases
B. the cell-cycle period after DNA replication when cells prepare for mitosis and assess replicated DNA
C. a tumor-suppressor transcription factor activated by cellular stress or DNA damage that can promote arrest, repair, senescence,
or apoptosis
D. a protein kinase whose activity depends on binding a cyclin and that drives cell-cycle transitions by phosphorylating targets
Answer: C
Explanation: The correct description of p53 is that it is a tumor-suppressor transcription factor activated by cellular stress or DNA damage
that can promote arrest, repair, senescence, or apoptosis. DNA damage causes a cell to stop dividing and induce genes that help prevent
propagation of mutations. The other choices define different concepts and therefore do not fit this term.
3 A daughter cell increases in size and decides whether conditions are suitable for another division cycle.
What is the best explanation for the finding?
A. G2 phase
B. G1 phase
C. cyclin
D. Rb protein
Answer: B
Explanation: G1 phase best explains the observation because it is the cell-cycle period after mitosis when cells grow, perform functions,
and prepare for DNA replication. The scenario is a direct application of that function or mechanism. The distractors are related cell-biology
concepts but do not account for the key feature described.
Original practice questions with explanations Page 2
,PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
4 A cell undergoes the following change: Blocking it under anaerobic conditions would limit NAD+
regeneration and slow glycolysis. Which target was most likely altered?
A. fermentation
B. FADH2
C. NADH
D. pyruvate dehydrogenase complex
Answer: A
Explanation: Fermentation is the best match. It is a pathway that regenerates NAD+ from NADH when the respiratory chain cannot
oxidize NADH efficiently, so the stated consequence follows directly when its function is changed. The other options can influence cellular
behavior, but they do not most directly predict this specific outcome.
5 Which term-description pairing is correct?
A. oxygen - a compound or process that dissipates the proton gradient without producing ATP, allowing respiration to continue with
energy released as heat
B. electron transport chain - the terminal electron acceptor of the mitochondrial respiratory chain under aerobic conditions
C. uncoupler - a series of inner mitochondrial membrane complexes that transfer electrons and use released energy to pump
protons
D. ATP synthase - a rotary membrane enzyme that uses proton flow down an electrochemical gradient to drive ATP formation
Answer: D
Explanation: The correct pairing is ATP synthase with its defining feature: a rotary membrane enzyme that uses proton flow down an
electrochemical gradient to drive ATP formation. Protons return to the mitochondrial matrix through a protein complex that converts ADP
and phosphate into ATP. The remaining pairs intentionally mismatch a term with the description of a different concept.
6 Which option is most accurately defined as a specialized division program that reduces chromosome
number and increases genetic diversity in gamete-producing lineages?
A. metaphase checkpoint
B. meiosis
C. cohesin
D. kinesin
Answer: B
Explanation: Meiosis is correct because it is a specialized division program that reduces chromosome number and increases genetic
diversity in gamete-producing lineages. One diploid precursor ultimately generates haploid cells after two nuclear divisions. This match is
more specific than the related alternatives, which describe different structures, molecules, or processes.
7 Which statement best describes metaphase checkpoint?
A. a protein structure assembled on centromeric DNA that connects chromosomes to spindle microtubules
B. a surveillance mechanism that delays anaphase until chromosomes are properly attached to the spindle
C. a protease activated at anaphase onset that cleaves cohesin and permits sister chromatids to separate
D. physical division of the cytoplasm to produce separate daughter cells after nuclear division
Answer: B
Explanation: The correct description of metaphase checkpoint is that it is a surveillance mechanism that delays anaphase until
chromosomes are properly attached to the spindle. One kinetochore remains unattached, so sister chromatids are not yet allowed to
separate. The other choices define different concepts and therefore do not fit this term.
Original practice questions with explanations Page 3
, PASSPOINT PRO | GBIO 200 CELL BIOLOGY EXAM 3 - 125Q
8 Pyruvate enters mitochondria and is oxidatively decarboxylated before the citric acid cycle. Which
structure or process is most directly involved?
A. fermentation
B. pyruvate dehydrogenase complex
C. FADH2
D. glycolysis
Answer: B
Explanation: Pyruvate dehydrogenase complex best explains the observation because it is the mitochondrial enzyme complex that
converts pyruvate to acetyl-CoA while producing NADH and CO2. The scenario is a direct application of that function or mechanism. The
distractors are related cell-biology concepts but do not account for the key feature described.
9 A selective perturbation causes this outcome: Blocking DNA synthesis prevents normal completion of
this phase. Which process or structure is the best match?
A. Rb protein
B. cyclin
C. S phase
D. G1 phase
Answer: C
Explanation: S phase is the best match. It is the cell-cycle phase in which nuclear DNA is replicated, so the stated consequence follows
directly when its function is changed. The other options can influence cellular behavior, but they do not most directly predict this specific
outcome.
10 Which term-description pairing is correct?
A. cytokinesis - a protein structure assembled on centromeric DNA that connects chromosomes to spindle microtubules
B. cohesin - physical division of the cytoplasm to produce separate daughter cells after nuclear division
C. separase - a protease activated at anaphase onset that cleaves cohesin and permits sister chromatids to separate
D. kinetochore - a protein complex that holds replicated sister chromatids together until anaphase
Answer: C
Explanation: The correct pairing is separase with its defining feature: a protease activated at anaphase onset that cleaves cohesin and
permits sister chromatids to separate. A protease is released from inhibition just before chromatids move toward opposite spindle poles.
The remaining pairs intentionally mismatch a term with the description of a different concept.
11 Identify the concept described here: an anti-apoptotic protein family member that helps preserve
mitochondrial outer membrane integrity.
A. apoptosis
B. cytochrome c release
C. caspase
D. Bcl-2
Answer: D
Explanation: Bcl-2 is correct because it is an anti-apoptotic protein family member that helps preserve mitochondrial outer membrane
integrity. A survival protein prevents mitochondrial release of pro-apoptotic factors. This match is more specific than the related
alternatives, which describe different structures, molecules, or processes.
Original practice questions with explanations Page 4
