Molecular Biotechnology
Certification Examination
Questions and Correct
Answers (Verified Answers)
Plus Rationales 2026 Q&A |
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1. The molecule that stores genetic information in most living organisms is:
A. RNA
B. Protein
C. DNA
D. Lipid
Answer: C. DNA
Rationale: DNA (deoxyribonucleic acid) is the primary hereditary material in nearly
all living organisms.
2. DNA is composed of repeating units called:
A. Amino acids
B. Fatty acids
C. Nucleotides
D. Monosaccharides
,Answer: C. Nucleotides
Rationale: DNA consists of nucleotides, each containing a sugar, phosphate group,
and nitrogenous base.
3. Which nitrogenous base is found in DNA but not RNA?
A. Uracil
B. Cytosine
C. Guanine
D. Thymine
Answer: D. Thymine
Rationale: DNA contains thymine, whereas RNA contains uracil instead of
thymine.
4. Which nitrogenous base replaces thymine in RNA?
A. Adenine
B. Cytosine
C. Uracil
D. Guanine
Answer: C. Uracil
Rationale: RNA contains uracil, which pairs with adenine during transcription.
5. DNA replication occurs before:
A. Protein synthesis only
B. Translation
C. Cell division
D. RNA degradation
Answer: C. Cell division
,Rationale: DNA must be replicated before cell division so each daughter cell
receives a complete genome.
6. The enzyme that synthesizes new DNA strands is:
A. RNA polymerase
B. DNA ligase
C. DNA polymerase
D. Helicase
Answer: C. DNA polymerase
Rationale: DNA polymerase adds nucleotides to synthesize a new DNA strand.
7. The enzyme that unwinds the DNA double helix during replication is:
A. Primase
B. Ligase
C. Helicase
D. Topoisomerase
Answer: C. Helicase
Rationale: Helicase separates the two DNA strands by breaking hydrogen bonds.
8. The enzyme that joins Okazaki fragments is:
A. DNA polymerase
B. Helicase
C. DNA ligase
D. Primase
Answer: C. DNA ligase
Rationale: DNA ligase seals breaks in the sugar-phosphate backbone.
, 9. Short DNA fragments synthesized on the lagging strand are called:
A. Operons
B. Exons
C. Okazaki fragments
D. Introns
Answer: C. Okazaki fragments
Rationale: The lagging strand is synthesized discontinuously as Okazaki fragments.
10. The process of producing RNA from a DNA template is called:
A. Replication
B. Translation
C. Transcription
D. Transformation
Answer: C. Transcription
Rationale: Transcription copies genetic information from DNA into RNA.
11. The enzyme responsible for transcription is:
A. DNA polymerase
B. Reverse transcriptase
C. RNA polymerase
D. DNA ligase
Answer: C. RNA polymerase
Rationale: RNA polymerase synthesizes RNA using DNA as the template.
12. Messenger RNA (mRNA) carries genetic information from the:
A. Ribosome to nucleus
B. Cytoplasm to membrane
Certification Examination
Questions and Correct
Answers (Verified Answers)
Plus Rationales 2026 Q&A |
Instant Download Pdf
1. The molecule that stores genetic information in most living organisms is:
A. RNA
B. Protein
C. DNA
D. Lipid
Answer: C. DNA
Rationale: DNA (deoxyribonucleic acid) is the primary hereditary material in nearly
all living organisms.
2. DNA is composed of repeating units called:
A. Amino acids
B. Fatty acids
C. Nucleotides
D. Monosaccharides
,Answer: C. Nucleotides
Rationale: DNA consists of nucleotides, each containing a sugar, phosphate group,
and nitrogenous base.
3. Which nitrogenous base is found in DNA but not RNA?
A. Uracil
B. Cytosine
C. Guanine
D. Thymine
Answer: D. Thymine
Rationale: DNA contains thymine, whereas RNA contains uracil instead of
thymine.
4. Which nitrogenous base replaces thymine in RNA?
A. Adenine
B. Cytosine
C. Uracil
D. Guanine
Answer: C. Uracil
Rationale: RNA contains uracil, which pairs with adenine during transcription.
5. DNA replication occurs before:
A. Protein synthesis only
B. Translation
C. Cell division
D. RNA degradation
Answer: C. Cell division
,Rationale: DNA must be replicated before cell division so each daughter cell
receives a complete genome.
6. The enzyme that synthesizes new DNA strands is:
A. RNA polymerase
B. DNA ligase
C. DNA polymerase
D. Helicase
Answer: C. DNA polymerase
Rationale: DNA polymerase adds nucleotides to synthesize a new DNA strand.
7. The enzyme that unwinds the DNA double helix during replication is:
A. Primase
B. Ligase
C. Helicase
D. Topoisomerase
Answer: C. Helicase
Rationale: Helicase separates the two DNA strands by breaking hydrogen bonds.
8. The enzyme that joins Okazaki fragments is:
A. DNA polymerase
B. Helicase
C. DNA ligase
D. Primase
Answer: C. DNA ligase
Rationale: DNA ligase seals breaks in the sugar-phosphate backbone.
, 9. Short DNA fragments synthesized on the lagging strand are called:
A. Operons
B. Exons
C. Okazaki fragments
D. Introns
Answer: C. Okazaki fragments
Rationale: The lagging strand is synthesized discontinuously as Okazaki fragments.
10. The process of producing RNA from a DNA template is called:
A. Replication
B. Translation
C. Transcription
D. Transformation
Answer: C. Transcription
Rationale: Transcription copies genetic information from DNA into RNA.
11. The enzyme responsible for transcription is:
A. DNA polymerase
B. Reverse transcriptase
C. RNA polymerase
D. DNA ligase
Answer: C. RNA polymerase
Rationale: RNA polymerase synthesizes RNA using DNA as the template.
12. Messenger RNA (mRNA) carries genetic information from the:
A. Ribosome to nucleus
B. Cytoplasm to membrane
