BIOS 255 Week 5 Quiz Exam final (Latest
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. Which process repairs damaged DNA by using a
complementary strand as a template?
A. Base excision repair
B. Homologous recombination
C. Non-homologous end joining
D. Nucleotide excision repair
Correct Answer: B
Rationale: Homologous recombination uses a sister chromatid as a
template for accurate repair.
2. Which enzyme unwinds the DNA double helix during
replication?
A. DNA polymerase
B. Ligase
C. Helicase
D. Primase
Correct Answer: C
,Rationale: Helicase separates the two DNA strands at the
replication fork.
3. What is the role of primase in DNA replication?
A. Synthesizes RNA primers
B. Joins Okazaki fragments
C. Unwinds DNA
D. Proofreads DNA
Correct Answer: A
Rationale: Primase synthesizes short RNA primers to initiate DNA
synthesis.
4. Which strand is synthesized continuously during replication?
A. Lagging strand
B. Leading strand
C. Template strand
D. Okazaki strand
Correct Answer: B
Rationale: The leading strand is synthesized in the direction of the
replication fork.
5. Which strand is synthesized discontinuously?
A. Leading strand
B. Lagging strand
C. Template strand
,D. Coding strand
Correct Answer: B
Rationale: Lagging strand is synthesized as Okazaki fragments in
the opposite direction.
6. Which enzyme joins Okazaki fragments?
A. DNA polymerase
B. Ligase
C. Helicase
D. Primase
Correct Answer: B
Rationale: DNA ligase seals the gaps between Okazaki fragments.
7. Which mutation changes a codon to a stop codon?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
D. Frameshift mutation
Correct Answer: C
Rationale: Nonsense mutations introduce premature stop codons.
8. Which mutation does not alter the amino acid sequence?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
, D. Frameshift mutation
Correct Answer: A
Rationale: Silent mutations do not change the protein sequence.
9. Which mutation results from insertions or deletions that shift
the reading frame?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
D. Frameshift mutation
Correct Answer: D
Rationale: Frameshift mutations disrupt the codon reading frame.
10. Which RNA carries amino acids to the ribosome?
A. mRNA
B. tRNA
C. rRNA
D. snRNA
Correct Answer: B
Rationale: tRNA delivers amino acids corresponding to codons in
mRNA.
11. Which RNA forms the core of the ribosome?
A. mRNA
B. tRNA
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. Which process repairs damaged DNA by using a
complementary strand as a template?
A. Base excision repair
B. Homologous recombination
C. Non-homologous end joining
D. Nucleotide excision repair
Correct Answer: B
Rationale: Homologous recombination uses a sister chromatid as a
template for accurate repair.
2. Which enzyme unwinds the DNA double helix during
replication?
A. DNA polymerase
B. Ligase
C. Helicase
D. Primase
Correct Answer: C
,Rationale: Helicase separates the two DNA strands at the
replication fork.
3. What is the role of primase in DNA replication?
A. Synthesizes RNA primers
B. Joins Okazaki fragments
C. Unwinds DNA
D. Proofreads DNA
Correct Answer: A
Rationale: Primase synthesizes short RNA primers to initiate DNA
synthesis.
4. Which strand is synthesized continuously during replication?
A. Lagging strand
B. Leading strand
C. Template strand
D. Okazaki strand
Correct Answer: B
Rationale: The leading strand is synthesized in the direction of the
replication fork.
5. Which strand is synthesized discontinuously?
A. Leading strand
B. Lagging strand
C. Template strand
,D. Coding strand
Correct Answer: B
Rationale: Lagging strand is synthesized as Okazaki fragments in
the opposite direction.
6. Which enzyme joins Okazaki fragments?
A. DNA polymerase
B. Ligase
C. Helicase
D. Primase
Correct Answer: B
Rationale: DNA ligase seals the gaps between Okazaki fragments.
7. Which mutation changes a codon to a stop codon?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
D. Frameshift mutation
Correct Answer: C
Rationale: Nonsense mutations introduce premature stop codons.
8. Which mutation does not alter the amino acid sequence?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
, D. Frameshift mutation
Correct Answer: A
Rationale: Silent mutations do not change the protein sequence.
9. Which mutation results from insertions or deletions that shift
the reading frame?
A. Silent mutation
B. Missense mutation
C. Nonsense mutation
D. Frameshift mutation
Correct Answer: D
Rationale: Frameshift mutations disrupt the codon reading frame.
10. Which RNA carries amino acids to the ribosome?
A. mRNA
B. tRNA
C. rRNA
D. snRNA
Correct Answer: B
Rationale: tRNA delivers amino acids corresponding to codons in
mRNA.
11. Which RNA forms the core of the ribosome?
A. mRNA
B. tRNA
