BIOD210
DNA Replication, Transcription &
Translation
Comprehensive Test Review (Qns & Ans)
2025
1. Which of the following enzymes is responsible for unwinding
the DNA double helix during replication?
a) DNA polymerase
b) Helicase
c) Primase
d) Ligase
Correct ANS: b) Helicase
©/2025
, Rationale: Helicase unwinds the double-stranded DNA at the
replication fork, allowing for replication.
2. In eukaryotes, which polymerase is primarily responsible for
synthesizing mRNA?
a) DNA polymerase I
b) RNA polymerase I
c) RNA polymerase II
d) RNA polymerase III
Correct ANS: c) RNA polymerase II
Rationale: RNA polymerase II synthesizes pre-mRNA, which
is then processed into mature mRNA.
3. What is the role of the 5’ cap added during mRNA
processing?
a) To signal the start of translation
b) To protect the mRNA from degradation
c) To assist in ribosome binding
d) All of the above
Correct ANS: d) All of the above
Rationale: The 5’ cap serves multiple important functions,
including protecting mRNA and facilitating translation.
©/2025
, 4. Which of the following best describes the function of the
ribosome during translation?
a) It carries amino acids to the synthesizing polypeptide chain.
b) It catalyzes the formation of peptide bonds.
c) It unwinds the mRNA strand.
d) It terminates protein synthesis.
Correct ANS: b) It catalyzes the formation of peptide bonds.
Rationale: Ribosomes are the sites of protein synthesis where
peptide bonds between amino acids are formed.
5. During DNA replication, which of the following is true about
leading strand synthesis?
a) It is synthesized in a discontinuous fashion.
b) It requires RNA primers to initiate synthesis.
c) It is synthesized continuously in the direction of the
replication fork.
d) It does not require helicase.
Correct ANS: c) It is synthesized continuously in the direction
of the replication fork.
Rationale: The leading strand is synthesized continuously as
the DNA polymerase follows the helicase unwinding the DNA.
©/2025
DNA Replication, Transcription &
Translation
Comprehensive Test Review (Qns & Ans)
2025
1. Which of the following enzymes is responsible for unwinding
the DNA double helix during replication?
a) DNA polymerase
b) Helicase
c) Primase
d) Ligase
Correct ANS: b) Helicase
©/2025
, Rationale: Helicase unwinds the double-stranded DNA at the
replication fork, allowing for replication.
2. In eukaryotes, which polymerase is primarily responsible for
synthesizing mRNA?
a) DNA polymerase I
b) RNA polymerase I
c) RNA polymerase II
d) RNA polymerase III
Correct ANS: c) RNA polymerase II
Rationale: RNA polymerase II synthesizes pre-mRNA, which
is then processed into mature mRNA.
3. What is the role of the 5’ cap added during mRNA
processing?
a) To signal the start of translation
b) To protect the mRNA from degradation
c) To assist in ribosome binding
d) All of the above
Correct ANS: d) All of the above
Rationale: The 5’ cap serves multiple important functions,
including protecting mRNA and facilitating translation.
©/2025
, 4. Which of the following best describes the function of the
ribosome during translation?
a) It carries amino acids to the synthesizing polypeptide chain.
b) It catalyzes the formation of peptide bonds.
c) It unwinds the mRNA strand.
d) It terminates protein synthesis.
Correct ANS: b) It catalyzes the formation of peptide bonds.
Rationale: Ribosomes are the sites of protein synthesis where
peptide bonds between amino acids are formed.
5. During DNA replication, which of the following is true about
leading strand synthesis?
a) It is synthesized in a discontinuous fashion.
b) It requires RNA primers to initiate synthesis.
c) It is synthesized continuously in the direction of the
replication fork.
d) It does not require helicase.
Correct ANS: c) It is synthesized continuously in the direction
of the replication fork.
Rationale: The leading strand is synthesized continuously as
the DNA polymerase follows the helicase unwinding the DNA.
©/2025
