MDSC 515 Final Exam 2025 Questions and
Correct Answers Foundations of Medical Science
Exam Format: Multiple Choice with Answers and Rationales
Coverage: Systems-Based Pathophysiology, Microbiology, Pharmacology,
Hematology, Neurology, and More
Section 1: Cell Biology and Molecular Medicine
1. Which of the following processes occurs in the mitochondria?
A. Glycolysis
B. DNA replication
C. Fatty acid β-oxidation
D. Protein synthesis
Answer: C
Rationale: β-oxidation of fatty acids occurs in the mitochondria, while glycolysis
occurs in the cytoplasm.
2. Which phase of the cell cycle is primarily involved in DNA synthesis?
A. G1
B. S
,C. G2
D. M
Answer: B
Rationale: DNA replication occurs during the S (synthesis) phase.
3. Which RNA polymerase is responsible for mRNA transcription in eukaryotic
cells?
A. RNA Pol I
B. RNA Pol II
C. RNA Pol III
D. DNA polymerase
Answer: B
Rationale: RNA polymerase II transcribes mRNA in eukaryotes.
4. A mutation in the p53 gene is most likely to result in:
A. Increased cell differentiation
B. Increased apoptosis
C. Decreased cell cycle arrest
D. Improved DNA repair
Answer: C
Rationale: p53 normally halts the cell cycle for DNA repair or triggers apoptosis.
A mutation can reduce these effects.
5. Which of the following mechanisms contributes to epigenetic regulation?
A. Point mutations
,B. Histone acetylation
C. DNA replication errors
D. RNA splicing
Answer: B
Rationale: Epigenetic modifications include DNA methylation and histone
modifications (e.g., acetylation).
Section 2: Physiology and Homeostasis
6. The sodium-potassium pump is an example of:
A. Facilitated diffusion
B. Secondary active transport
C. Primary active transport
D. Passive transport
Answer: C
Rationale: The Na⁺/K⁺-ATPase uses ATP directly, making it a primary active
transporter.
7. Which hormone increases blood glucose levels by stimulating glycogenolysis?
A. Insulin
B. Glucagon
C. Cortisol
D. Aldosterone
Answer: B
Rationale: Glucagon acts on the liver to promote glycogenolysis and raise blood
glucose.
, 8. What effect does aldosterone have on the kidneys?
A. Increases potassium reabsorption
B. Increases sodium excretion
C. Increases sodium reabsorption
D. Inhibits ADH
Answer: C
Rationale: Aldosterone promotes sodium (and water) reabsorption and
potassium excretion.
9. During muscle contraction, calcium binds to:
A. Actin
B. Myosin
C. Tropomyosin
D. Troponin
Answer: D
Rationale: Calcium binds to troponin, initiating conformational changes that
allow myosin-actin interaction.
10. Which of the following best describes the Frank-Starling law of the heart?
A. Increased afterload increases contractility
B. Increased preload increases stroke volume
C. Increased heart rate increases end-diastolic volume
D. Decreased venous return increases stroke volume
Answer: B
Correct Answers Foundations of Medical Science
Exam Format: Multiple Choice with Answers and Rationales
Coverage: Systems-Based Pathophysiology, Microbiology, Pharmacology,
Hematology, Neurology, and More
Section 1: Cell Biology and Molecular Medicine
1. Which of the following processes occurs in the mitochondria?
A. Glycolysis
B. DNA replication
C. Fatty acid β-oxidation
D. Protein synthesis
Answer: C
Rationale: β-oxidation of fatty acids occurs in the mitochondria, while glycolysis
occurs in the cytoplasm.
2. Which phase of the cell cycle is primarily involved in DNA synthesis?
A. G1
B. S
,C. G2
D. M
Answer: B
Rationale: DNA replication occurs during the S (synthesis) phase.
3. Which RNA polymerase is responsible for mRNA transcription in eukaryotic
cells?
A. RNA Pol I
B. RNA Pol II
C. RNA Pol III
D. DNA polymerase
Answer: B
Rationale: RNA polymerase II transcribes mRNA in eukaryotes.
4. A mutation in the p53 gene is most likely to result in:
A. Increased cell differentiation
B. Increased apoptosis
C. Decreased cell cycle arrest
D. Improved DNA repair
Answer: C
Rationale: p53 normally halts the cell cycle for DNA repair or triggers apoptosis.
A mutation can reduce these effects.
5. Which of the following mechanisms contributes to epigenetic regulation?
A. Point mutations
,B. Histone acetylation
C. DNA replication errors
D. RNA splicing
Answer: B
Rationale: Epigenetic modifications include DNA methylation and histone
modifications (e.g., acetylation).
Section 2: Physiology and Homeostasis
6. The sodium-potassium pump is an example of:
A. Facilitated diffusion
B. Secondary active transport
C. Primary active transport
D. Passive transport
Answer: C
Rationale: The Na⁺/K⁺-ATPase uses ATP directly, making it a primary active
transporter.
7. Which hormone increases blood glucose levels by stimulating glycogenolysis?
A. Insulin
B. Glucagon
C. Cortisol
D. Aldosterone
Answer: B
Rationale: Glucagon acts on the liver to promote glycogenolysis and raise blood
glucose.
, 8. What effect does aldosterone have on the kidneys?
A. Increases potassium reabsorption
B. Increases sodium excretion
C. Increases sodium reabsorption
D. Inhibits ADH
Answer: C
Rationale: Aldosterone promotes sodium (and water) reabsorption and
potassium excretion.
9. During muscle contraction, calcium binds to:
A. Actin
B. Myosin
C. Tropomyosin
D. Troponin
Answer: D
Rationale: Calcium binds to troponin, initiating conformational changes that
allow myosin-actin interaction.
10. Which of the following best describes the Frank-Starling law of the heart?
A. Increased afterload increases contractility
B. Increased preload increases stroke volume
C. Increased heart rate increases end-diastolic volume
D. Decreased venous return increases stroke volume
Answer: B
