BIOS 251 Week 5 Quiz Exam final (Latest
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. Which phase of the cell cycle involves growth and preparation
for DNA replication?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Correct answer: A
Rationale: G1 phase is when the cell grows and prepares enzymes
and nucleotides for DNA replication.
2. Which phase of the cell cycle involves DNA replication?
A. G1 phase
B. S phase
C. G2 phase
,D. M phase
Correct answer: B
Rationale: S phase is dedicated to DNA synthesis to ensure each
daughter cell gets a complete genome.
3. Which checkpoint ensures DNA integrity before entering S
phase?
A. G1 checkpoint
B. G2 checkpoint
C. M checkpoint
D. S checkpoint
Correct answer: A
Rationale: The G1 checkpoint stops cells with damaged DNA from
replicating.
4. Which checkpoint ensures all chromosomes are attached to the
spindle before anaphase?
A. G1 checkpoint
B. G2 checkpoint
C. M checkpoint
D. S checkpoint
Correct answer: C
Rationale: The M checkpoint prevents premature separation of
chromosomes.
,5. Which enzyme unwinds the DNA double helix?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: B
Rationale: Helicase breaks hydrogen bonds between DNA strands to
open the helix.
6. Which enzyme synthesizes new DNA strands?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: A
Rationale: DNA polymerase adds nucleotides complementary to the
DNA template strand.
7. Which enzyme joins Okazaki fragments on the lagging strand?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: C
, Rationale: Ligase seals the nicks between Okazaki fragments to
create a continuous strand.
8. Which enzyme synthesizes RNA primers for DNA replication?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: D
Rationale: Primase creates short RNA primers that DNA
polymerase can extend.
9. Which organelle is responsible for protein synthesis for
secretion?
A. Rough ER
B. Smooth ER
C. Golgi apparatus
D. Ribosome
Correct answer: A
Rationale: Rough ER-bound ribosomes synthesize proteins destined
for secretion or membranes.
10. Which organelle modifies and packages proteins?
Update ) Anatomy and
Physiology IV with Lab | Questions &
Answers | 100% Correct | Grade A -
Chamberlain
1. Which phase of the cell cycle involves growth and preparation
for DNA replication?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Correct answer: A
Rationale: G1 phase is when the cell grows and prepares enzymes
and nucleotides for DNA replication.
2. Which phase of the cell cycle involves DNA replication?
A. G1 phase
B. S phase
C. G2 phase
,D. M phase
Correct answer: B
Rationale: S phase is dedicated to DNA synthesis to ensure each
daughter cell gets a complete genome.
3. Which checkpoint ensures DNA integrity before entering S
phase?
A. G1 checkpoint
B. G2 checkpoint
C. M checkpoint
D. S checkpoint
Correct answer: A
Rationale: The G1 checkpoint stops cells with damaged DNA from
replicating.
4. Which checkpoint ensures all chromosomes are attached to the
spindle before anaphase?
A. G1 checkpoint
B. G2 checkpoint
C. M checkpoint
D. S checkpoint
Correct answer: C
Rationale: The M checkpoint prevents premature separation of
chromosomes.
,5. Which enzyme unwinds the DNA double helix?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: B
Rationale: Helicase breaks hydrogen bonds between DNA strands to
open the helix.
6. Which enzyme synthesizes new DNA strands?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: A
Rationale: DNA polymerase adds nucleotides complementary to the
DNA template strand.
7. Which enzyme joins Okazaki fragments on the lagging strand?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: C
, Rationale: Ligase seals the nicks between Okazaki fragments to
create a continuous strand.
8. Which enzyme synthesizes RNA primers for DNA replication?
A. DNA polymerase
B. Helicase
C. Ligase
D. Primase
Correct answer: D
Rationale: Primase creates short RNA primers that DNA
polymerase can extend.
9. Which organelle is responsible for protein synthesis for
secretion?
A. Rough ER
B. Smooth ER
C. Golgi apparatus
D. Ribosome
Correct answer: A
Rationale: Rough ER-bound ribosomes synthesize proteins destined
for secretion or membranes.
10. Which organelle modifies and packages proteins?
