University of Michigan
4 MAXE · 171 OIB
★ ★
M College of Literature, Science & the Arts — Department of Biology
EST. 1817
ARTES · SCIENTIA · VERITAS
Bio 171 Exam 4
C E L LU L A R R E S P I RAT I O N · E TC · F E R M E N TAT I O N · M I TO S I S · M E I O S I S · G E N E T I CS
INSTITUTION University of Michigan PROGRAM Bachelor of Science — Biology
COURSE CODE BIO 171 COURSE TITLE Introduction to Molecular &
Cellular Biology
ACADEMIC YEAR EXAM TITLE Bio 171 Exam 4
TOTAL QUESTIONS 214 Questions FORMAT Multiple Choice — Select the
Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question unless otherwise instructed.
▸ This examination covers oxidative phosphorylation, the electron transport chain, fermentation, mitosis,
meiosis, chromosomal inheritance, and Mendelian genetics.
▸ Questions address ATP synthesis, chemiosmosis, cell cycle regulation, chromosomal variation, and
principles of heredity.
▸ Correct answers and explanatory rationales appear below each question for review purposes.
▸ All content reflects standard introductory biology curriculum for BIO 171 at the University of Michigan.
, SECTION I — CELLULAR RESPIRATION, CELL DIVISION &
Questions 1 – 214
GENETICS
1. Prior to oxidative phosphorylation, what has been produced by the preceding stages of
cellular respiration?
A. 6 CO2, 4 ATP, 10 NADH, 2 FADH2
B. 6 CO2, 2 ATP, 8 NADH, 4 FADH2
C. 4 CO2, 4 ATP, 12 NADH, 2 FADH2
D. 6 CO2, 2 ATP, 10 NADH, 0 FADH2
CORRECT ANSWER A — 6 CO2, 4 ATP, 10 NADH, 2 FADH2
RATIONALE Before oxidative phosphorylation, glycolysis (2 ATP, 2 NADH), pyruvate oxidation
(2 NADH, 2 CO2), and the citric acid cycle (2 ATP/GTP, 6 NADH, 2 FADH2, 4 CO2)
have produced a total of 6 CO2, 4 ATP (substrate-level), 10 NADH, and 2 FADH2 per
glucose. These carriers deliver electrons to the ETC, driving the majority of ATP
production.
2. What is the final electron acceptor of the electron transport chain?
A. NAD+
B. Oxygen
C. Carbon dioxide
D. ATP
CORRECT ANSWER B — Oxygen
RATIONALE Oxygen is the final electron acceptor. Its high electronegativity pulls electrons
through the chain, driving proton pumping. When oxygen accepts electrons, it
combines with H+ to form water. Without oxygen, the ETC backs up and oxidative
phosphorylation ceases.
,3. What is the last step of cellular respiration?
A. Glycolysis
B. Citric acid cycle
C. Oxidative phosphorylation
D. Pyruvate oxidation
CORRECT ANSWER C — Oxidative phosphorylation
RATIONALE Oxidative phosphorylation is the final stage of aerobic respiration, occurring in
the inner mitochondrial membrane. It couples electron transport with ATP
synthesis, producing approximately 26-28 ATP per glucose — the vast majority of
ATP from respiration.
4. Where does oxidative phosphorylation occur?
A. Cytoplasm
B. Inner mitochondrial membrane
C. Mitochondrial matrix
D. Outer mitochondrial membrane
CORRECT ANSWER B — Inner mitochondrial membrane
RATIONALE The ETC complexes and ATP synthase are embedded in the inner mitochondrial
membrane. The folded cristae increase surface area. The intermembrane space
accumulates protons, creating the gradient that drives ATP synthesis.
, 5. How many protein complexes are there in the ETC?
A. 2
B. 3
C. 4
D. 5
CORRECT ANSWER C—4
RATIONALE The ETC has four major complexes: I (NADH dehydrogenase), II (succinate
reductase), III (cytochrome b-c1), and IV (cytochrome oxidase). Two mobile
carriers — CoQ and cytochrome c — shuttle electrons between them.
6. What is nondisjunction?
A. Normal chromosome separation during anaphase
B. Changes in chromosome number due to abnormal sorting in cell division
C. Exchange of genetic material between non-sister chromatids
D. Chromosome duplication during S phase
CORRECT ANSWER B — Changes in chromosome number due to abnormal sorting in cell
division
RATIONALE Nondisjunction is the failure of chromosomes to separate properly during meiosis
I or II, producing gametes with abnormal chromosome numbers. Fertilization
results in aneuploidy — trisomy or monosomy — causing conditions like Down
syndrome.
4 MAXE · 171 OIB
★ ★
M College of Literature, Science & the Arts — Department of Biology
EST. 1817
ARTES · SCIENTIA · VERITAS
Bio 171 Exam 4
C E L LU L A R R E S P I RAT I O N · E TC · F E R M E N TAT I O N · M I TO S I S · M E I O S I S · G E N E T I CS
INSTITUTION University of Michigan PROGRAM Bachelor of Science — Biology
COURSE CODE BIO 171 COURSE TITLE Introduction to Molecular &
Cellular Biology
ACADEMIC YEAR EXAM TITLE Bio 171 Exam 4
TOTAL QUESTIONS 214 Questions FORMAT Multiple Choice — Select the
Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question unless otherwise instructed.
▸ This examination covers oxidative phosphorylation, the electron transport chain, fermentation, mitosis,
meiosis, chromosomal inheritance, and Mendelian genetics.
▸ Questions address ATP synthesis, chemiosmosis, cell cycle regulation, chromosomal variation, and
principles of heredity.
▸ Correct answers and explanatory rationales appear below each question for review purposes.
▸ All content reflects standard introductory biology curriculum for BIO 171 at the University of Michigan.
, SECTION I — CELLULAR RESPIRATION, CELL DIVISION &
Questions 1 – 214
GENETICS
1. Prior to oxidative phosphorylation, what has been produced by the preceding stages of
cellular respiration?
A. 6 CO2, 4 ATP, 10 NADH, 2 FADH2
B. 6 CO2, 2 ATP, 8 NADH, 4 FADH2
C. 4 CO2, 4 ATP, 12 NADH, 2 FADH2
D. 6 CO2, 2 ATP, 10 NADH, 0 FADH2
CORRECT ANSWER A — 6 CO2, 4 ATP, 10 NADH, 2 FADH2
RATIONALE Before oxidative phosphorylation, glycolysis (2 ATP, 2 NADH), pyruvate oxidation
(2 NADH, 2 CO2), and the citric acid cycle (2 ATP/GTP, 6 NADH, 2 FADH2, 4 CO2)
have produced a total of 6 CO2, 4 ATP (substrate-level), 10 NADH, and 2 FADH2 per
glucose. These carriers deliver electrons to the ETC, driving the majority of ATP
production.
2. What is the final electron acceptor of the electron transport chain?
A. NAD+
B. Oxygen
C. Carbon dioxide
D. ATP
CORRECT ANSWER B — Oxygen
RATIONALE Oxygen is the final electron acceptor. Its high electronegativity pulls electrons
through the chain, driving proton pumping. When oxygen accepts electrons, it
combines with H+ to form water. Without oxygen, the ETC backs up and oxidative
phosphorylation ceases.
,3. What is the last step of cellular respiration?
A. Glycolysis
B. Citric acid cycle
C. Oxidative phosphorylation
D. Pyruvate oxidation
CORRECT ANSWER C — Oxidative phosphorylation
RATIONALE Oxidative phosphorylation is the final stage of aerobic respiration, occurring in
the inner mitochondrial membrane. It couples electron transport with ATP
synthesis, producing approximately 26-28 ATP per glucose — the vast majority of
ATP from respiration.
4. Where does oxidative phosphorylation occur?
A. Cytoplasm
B. Inner mitochondrial membrane
C. Mitochondrial matrix
D. Outer mitochondrial membrane
CORRECT ANSWER B — Inner mitochondrial membrane
RATIONALE The ETC complexes and ATP synthase are embedded in the inner mitochondrial
membrane. The folded cristae increase surface area. The intermembrane space
accumulates protons, creating the gradient that drives ATP synthesis.
, 5. How many protein complexes are there in the ETC?
A. 2
B. 3
C. 4
D. 5
CORRECT ANSWER C—4
RATIONALE The ETC has four major complexes: I (NADH dehydrogenase), II (succinate
reductase), III (cytochrome b-c1), and IV (cytochrome oxidase). Two mobile
carriers — CoQ and cytochrome c — shuttle electrons between them.
6. What is nondisjunction?
A. Normal chromosome separation during anaphase
B. Changes in chromosome number due to abnormal sorting in cell division
C. Exchange of genetic material between non-sister chromatids
D. Chromosome duplication during S phase
CORRECT ANSWER B — Changes in chromosome number due to abnormal sorting in cell
division
RATIONALE Nondisjunction is the failure of chromosomes to separate properly during meiosis
I or II, producing gametes with abnormal chromosome numbers. Fertilization
results in aneuploidy — trisomy or monosomy — causing conditions like Down
syndrome.
