CHEM 210 BIOCHEMISTRY MODULE 4 EXAM ACTUAL
2026/2027 | Geneva College | Complete Questions & Verified
Answers | Pass Guaranteed - A+ Graded
Section 1: Glycolysis & Gluconeogenesis (Q1-15)
Q1. A cell undergoes anaerobic glycolysis starting from one molecule of glucose. After
accounting for the investment phase and the payoff phase, what is the net yield of ATP
and NADH per glucose molecule?
A. 4 ATP and 2 NADH
B. 2 ATP and 4 NADH
C. 2 ATP (net) and 2 NADH [CORRECT]
D. 4 ATP (net) and 4 NADH
Rationale: Glycolysis consumes 2 ATP in the investment phase and produces 4 ATP in
the payoff phase, yielding a net of 2 ATP. It also produces 2 NADH per glucose. The
other options confuse gross versus net ATP or incorrectly double the NADH yield.
Correct Answer: C
Q2. A researcher isolates the enzymes of the glycolytic pathway from a cell lysate. In
which cellular compartment are these enzymes primarily located?
A. Mitochondrial matrix
B. Inner mitochondrial membrane
C. Cytoplasm (cytosol) [CORRECT]
D. Peroxisome
,Rationale: All ten reactions of glycolysis occur in the cytoplasm (cytosol). The
mitochondrial matrix houses the TCA cycle and beta-oxidation, while the inner
mitochondrial membrane contains the electron transport chain.
Correct Answer: C
Q3. In a hepatocyte, phosphofructokinase-1 (PFK-1) activity is being studied. Which of
the following molecules would allosterically activate PFK-1 to stimulate glycolytic flux?
A. ATP and citrate
B. AMP and fructose-2,6-bisphosphate [CORRECT]
C. Glucose-6-phosphate and NADH
D. Acetyl-CoA and succinate
Rationale: PFK-1 is the key regulatory enzyme of glycolysis and is activated by AMP,
ADP, and fructose-2,6-bisphosphate. It is inhibited by ATP and citrate, which signal high
energy status. The other options list inhibitors or unrelated metabolites.
Correct Answer: B
Q4. A student is asked to identify the three irreversible steps of glycolysis that must be
bypassed during gluconeogenesis. Which enzyme catalyzes the first irreversible step in
glycolysis, trapping glucose inside the cell?
A. Glucokinase/hexokinase [CORRECT]
B. Phosphofructokinase-1
C. Pyruvate kinase
D. Phosphoglycerate kinase
Rationale: The three irreversible steps of glycolysis are catalyzed by
hexokinase/glucokinase (step 1), PFK-1 (step 3), and pyruvate kinase (step 10).
Glucokinase/hexokinase phosphorylates glucose to glucose-6-phosphate, trapping it in
the cell.
Correct Answer: A
, Q5. A patient with a rare genetic disorder presents with hemolytic anemia due to
unstable red blood cell membranes. The defect is traced to a mutation in the gene
encoding pyruvate kinase. Which of the following best describes the normal allosteric
regulation of pyruvate kinase in the liver?
A. Activated by ATP; inhibited by fructose-1,6-bisphosphate
B. Activated by fructose-1,6-bisphosphate; inhibited by ATP and alanine [CORRECT]
C. Activated by citrate; inhibited by AMP
D. Activated by glucagon; inhibited by insulin
Rationale: Pyruvate kinase is activated by fructose-1,6-bisphosphate (feed-forward
activation) and inhibited by ATP and alanine (signaling abundant energy and building
blocks). Glucagon promotes phosphorylation and inhibition of pyruvate kinase.
Correct Answer: B
Q6. During gluconeogenesis, the conversion of pyruvate to phosphoenolpyruvate (PEP)
requires two enzymes to bypass the pyruvate kinase step. Which two enzymes catalyze
this bypass?
A. Pyruvate dehydrogenase and citrate synthase
B. Pyruvate carboxylase and phosphoenolpyruvate carboxykinase (PEPCK) [CORRECT]
C. Lactate dehydrogenase and alanine transaminase
D. Hexokinase and glucose-6-phosphatase
Rationale: The pyruvate to PEP bypass in gluconeogenesis requires pyruvate
carboxylase (pyruvate → oxaloacetate in mitochondria) and PEPCK (oxaloacetate →
PEP in cytosol). This bypasses the irreversible pyruvate kinase reaction of glycolysis.
Correct Answer: B
Q7. In the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) reaction of glycolysis,
which cofactor is required as the electron acceptor?
A. FAD
B. NAD+ [CORRECT]
C. NADP+
D. Thiamine pyrophosphate
2026/2027 | Geneva College | Complete Questions & Verified
Answers | Pass Guaranteed - A+ Graded
Section 1: Glycolysis & Gluconeogenesis (Q1-15)
Q1. A cell undergoes anaerobic glycolysis starting from one molecule of glucose. After
accounting for the investment phase and the payoff phase, what is the net yield of ATP
and NADH per glucose molecule?
A. 4 ATP and 2 NADH
B. 2 ATP and 4 NADH
C. 2 ATP (net) and 2 NADH [CORRECT]
D. 4 ATP (net) and 4 NADH
Rationale: Glycolysis consumes 2 ATP in the investment phase and produces 4 ATP in
the payoff phase, yielding a net of 2 ATP. It also produces 2 NADH per glucose. The
other options confuse gross versus net ATP or incorrectly double the NADH yield.
Correct Answer: C
Q2. A researcher isolates the enzymes of the glycolytic pathway from a cell lysate. In
which cellular compartment are these enzymes primarily located?
A. Mitochondrial matrix
B. Inner mitochondrial membrane
C. Cytoplasm (cytosol) [CORRECT]
D. Peroxisome
,Rationale: All ten reactions of glycolysis occur in the cytoplasm (cytosol). The
mitochondrial matrix houses the TCA cycle and beta-oxidation, while the inner
mitochondrial membrane contains the electron transport chain.
Correct Answer: C
Q3. In a hepatocyte, phosphofructokinase-1 (PFK-1) activity is being studied. Which of
the following molecules would allosterically activate PFK-1 to stimulate glycolytic flux?
A. ATP and citrate
B. AMP and fructose-2,6-bisphosphate [CORRECT]
C. Glucose-6-phosphate and NADH
D. Acetyl-CoA and succinate
Rationale: PFK-1 is the key regulatory enzyme of glycolysis and is activated by AMP,
ADP, and fructose-2,6-bisphosphate. It is inhibited by ATP and citrate, which signal high
energy status. The other options list inhibitors or unrelated metabolites.
Correct Answer: B
Q4. A student is asked to identify the three irreversible steps of glycolysis that must be
bypassed during gluconeogenesis. Which enzyme catalyzes the first irreversible step in
glycolysis, trapping glucose inside the cell?
A. Glucokinase/hexokinase [CORRECT]
B. Phosphofructokinase-1
C. Pyruvate kinase
D. Phosphoglycerate kinase
Rationale: The three irreversible steps of glycolysis are catalyzed by
hexokinase/glucokinase (step 1), PFK-1 (step 3), and pyruvate kinase (step 10).
Glucokinase/hexokinase phosphorylates glucose to glucose-6-phosphate, trapping it in
the cell.
Correct Answer: A
, Q5. A patient with a rare genetic disorder presents with hemolytic anemia due to
unstable red blood cell membranes. The defect is traced to a mutation in the gene
encoding pyruvate kinase. Which of the following best describes the normal allosteric
regulation of pyruvate kinase in the liver?
A. Activated by ATP; inhibited by fructose-1,6-bisphosphate
B. Activated by fructose-1,6-bisphosphate; inhibited by ATP and alanine [CORRECT]
C. Activated by citrate; inhibited by AMP
D. Activated by glucagon; inhibited by insulin
Rationale: Pyruvate kinase is activated by fructose-1,6-bisphosphate (feed-forward
activation) and inhibited by ATP and alanine (signaling abundant energy and building
blocks). Glucagon promotes phosphorylation and inhibition of pyruvate kinase.
Correct Answer: B
Q6. During gluconeogenesis, the conversion of pyruvate to phosphoenolpyruvate (PEP)
requires two enzymes to bypass the pyruvate kinase step. Which two enzymes catalyze
this bypass?
A. Pyruvate dehydrogenase and citrate synthase
B. Pyruvate carboxylase and phosphoenolpyruvate carboxykinase (PEPCK) [CORRECT]
C. Lactate dehydrogenase and alanine transaminase
D. Hexokinase and glucose-6-phosphatase
Rationale: The pyruvate to PEP bypass in gluconeogenesis requires pyruvate
carboxylase (pyruvate → oxaloacetate in mitochondria) and PEPCK (oxaloacetate →
PEP in cytosol). This bypasses the irreversible pyruvate kinase reaction of glycolysis.
Correct Answer: B
Q7. In the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) reaction of glycolysis,
which cofactor is required as the electron acceptor?
A. FAD
B. NAD+ [CORRECT]
C. NADP+
D. Thiamine pyrophosphate
