BIO101 Molecular Biology Midterm Exam Review 2025 (With Solns)

BIO101 Molecular Biology

Midterm Exam Review (Qns & Ans)

2025

1. What is the primary function of messenger RNA (mRNA) in
molecular biology?
A. Catalyzing chemical reactions
B. Carrying genetic information from DNA to the ribosome for
protein synthesis
C. Transporting amino acids to ribosomes
D. Protecting the DNA molecule from damage
ANS: B. Carrying genetic information from DNA to the
ribosome for protein synthesis
Rationale: mRNA serves as the intermediate template in
translating genetic information from DNA into proteins.



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,2. Which of the following enzymes is responsible for unwinding
DNA during replication?
A. DNA ligase
B. DNA polymerase
C. Helicase
D. Topoisomerase
ANS: C. Helicase
Rationale: Helicase unwinds the DNA double helix to prepare
for replication.


3. What is the central dogma of molecular biology?
A. RNA → DNA → Protein
B. DNA → RNA → Protein
C. Protein → RNA → DNA
D. RNA → Protein → DNA
ANS: B. DNA → RNA → Protein
Rationale: This concept outlines the flow of genetic
information from DNA to RNA and subsequently to protein
synthesis.


4. Which molecular process involves the removal of introns
from pre-mRNA?
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, A. Translation
B. Transcription
C. Splicing
D. Replication
ANS: C. Splicing
Rationale: Splicing removes non-coding introns, producing
mature mRNA ready for translation.


5. In molecular biology, which of the following techniques is
used to amplify DNA fragments?
A. Gel electrophoresis
B. Polymerase chain reaction (PCR)
C. Southern blotting
D. Immunohistochemistry
ANS: B. Polymerase chain reaction (PCR)
Rationale: PCR is a method used to exponentially amplify
specific DNA sequences.


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