NUR 230 EXAM 4 – GALEN OB/PEDS (2026)
QUESTIONS AND CORRECT ANSWERS WITH
DETAILED RATIONALES
Section 1: Biology & Biochemistry (Questions 1-50)
1. Which organelle is responsible for the synthesis of ATP through aerobic
respiration?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Endoplasmic reticulum
Correct Answer: C
Rationale: Mitochondria are the powerhouses of the cell, generating ATP via
oxidative phosphorylation. Ribosomes synthesize proteins, the Golgi modifies
proteins, and the ER is involved in synthesis and transport.
2. What is the primary function of DNA polymerase during DNA replication?
A) Unwind the double helix
B) Synthesize RNA primers
C) Add nucleotides to the growing DNA strand
D) Join Okazaki fragments
Correct Answer: C
,Rationale: DNA polymerase catalyzes the addition of deoxynucleotides to the
3' end of a growing DNA strand. Helicase unwinds DNA, primase synthesizes
RNA primers, and ligase joins fragments.
3. Which of the following is an example of a competitive inhibitor?
A) Cyanide binding to cytochrome c oxidase
B) Malonate binding to succinate dehydrogenase
C) Heavy metals binding to allosteric sites
D) Phosphate groups regulating glycogen phosphorylase
Correct Answer: B
Rationale: Malonate is structurally similar to succinate and competes for the
active site of succinate dehydrogenase. Cyanide is a non-competitive inhibitor,
and the others are allosteric regulators.
4. The "wobble" hypothesis explains which phenomenon?
A) The degenerate nature of the genetic code
B) The ability of a single tRNA to recognize more than one codon
C) The proofreading ability of DNA polymerase
D) The excision of introns from mRNA
Correct Answer: B
Rationale: The wobble hypothesis posits that the base at the 5' end of the
anticodon can pair with multiple bases at the 3' end of the codon, allowing a
single tRNA to bind to multiple codons.
5. In a hypertonic solution, an animal cell will most likely:
A) Swell and lyse
B) Shrink and crenate
,C) Remain unchanged
D) Burst
Correct Answer: B
Rationale: A hypertonic solution has a higher solute concentration outside the
cell. Water moves out of the cell via osmosis, causing the cell to shrink
(crenate).
6. Which of the following is NOT a type of RNA?
A) Messenger RNA
B) Transfer RNA
C) Regulatory RNA
D) Genomic RNA
Correct Answer: D
Rationale: Genomic RNA is a general term for the genetic material of some
viruses, not a standard classification of RNA types found in cells. The main
types are mRNA, tRNA, rRNA, and regulatory RNAs.
7. Where does the Calvin cycle take place in a plant cell?
A) Thylakoid membrane
B) Stroma of the chloroplast
C) Inner mitochondrial membrane
D) Cytoplasm
Correct Answer: B
Rationale: The Calvin cycle, which fixes CO2 into sugars, occurs in the stroma
(the fluid-filled space) of the chloroplast. The thylakoid membrane is where
the light-dependent reactions occur.
, 8. A mutation that changes a codon from UUU (Phenylalanine) to UUC
(Phenylalanine) is a:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Correct Answer: C
Rationale: The mutation does not change the amino acid, making it a silent
mutation (due to the degeneracy of the genetic code).
9. What is the role of NADH in cellular respiration?
A) To act as a final electron acceptor
B) To donate electrons to the electron transport chain
C) To phosphorylate ADP directly
D) To fix carbon dioxide
Correct Answer: B
Rationale: NADH is an electron carrier that donates its high-energy electrons
to the electron transport chain (ETC). Oxygen is the final electron acceptor.
10. Which of the following is NOT a characteristic of enzymes?
A) They are consumed in the reaction
B) They lower activation energy
C) They are specific to a substrate
D) They are proteins
Correct Answer: A
QUESTIONS AND CORRECT ANSWERS WITH
DETAILED RATIONALES
Section 1: Biology & Biochemistry (Questions 1-50)
1. Which organelle is responsible for the synthesis of ATP through aerobic
respiration?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Endoplasmic reticulum
Correct Answer: C
Rationale: Mitochondria are the powerhouses of the cell, generating ATP via
oxidative phosphorylation. Ribosomes synthesize proteins, the Golgi modifies
proteins, and the ER is involved in synthesis and transport.
2. What is the primary function of DNA polymerase during DNA replication?
A) Unwind the double helix
B) Synthesize RNA primers
C) Add nucleotides to the growing DNA strand
D) Join Okazaki fragments
Correct Answer: C
,Rationale: DNA polymerase catalyzes the addition of deoxynucleotides to the
3' end of a growing DNA strand. Helicase unwinds DNA, primase synthesizes
RNA primers, and ligase joins fragments.
3. Which of the following is an example of a competitive inhibitor?
A) Cyanide binding to cytochrome c oxidase
B) Malonate binding to succinate dehydrogenase
C) Heavy metals binding to allosteric sites
D) Phosphate groups regulating glycogen phosphorylase
Correct Answer: B
Rationale: Malonate is structurally similar to succinate and competes for the
active site of succinate dehydrogenase. Cyanide is a non-competitive inhibitor,
and the others are allosteric regulators.
4. The "wobble" hypothesis explains which phenomenon?
A) The degenerate nature of the genetic code
B) The ability of a single tRNA to recognize more than one codon
C) The proofreading ability of DNA polymerase
D) The excision of introns from mRNA
Correct Answer: B
Rationale: The wobble hypothesis posits that the base at the 5' end of the
anticodon can pair with multiple bases at the 3' end of the codon, allowing a
single tRNA to bind to multiple codons.
5. In a hypertonic solution, an animal cell will most likely:
A) Swell and lyse
B) Shrink and crenate
,C) Remain unchanged
D) Burst
Correct Answer: B
Rationale: A hypertonic solution has a higher solute concentration outside the
cell. Water moves out of the cell via osmosis, causing the cell to shrink
(crenate).
6. Which of the following is NOT a type of RNA?
A) Messenger RNA
B) Transfer RNA
C) Regulatory RNA
D) Genomic RNA
Correct Answer: D
Rationale: Genomic RNA is a general term for the genetic material of some
viruses, not a standard classification of RNA types found in cells. The main
types are mRNA, tRNA, rRNA, and regulatory RNAs.
7. Where does the Calvin cycle take place in a plant cell?
A) Thylakoid membrane
B) Stroma of the chloroplast
C) Inner mitochondrial membrane
D) Cytoplasm
Correct Answer: B
Rationale: The Calvin cycle, which fixes CO2 into sugars, occurs in the stroma
(the fluid-filled space) of the chloroplast. The thylakoid membrane is where
the light-dependent reactions occur.
, 8. A mutation that changes a codon from UUU (Phenylalanine) to UUC
(Phenylalanine) is a:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Correct Answer: C
Rationale: The mutation does not change the amino acid, making it a silent
mutation (due to the degeneracy of the genetic code).
9. What is the role of NADH in cellular respiration?
A) To act as a final electron acceptor
B) To donate electrons to the electron transport chain
C) To phosphorylate ADP directly
D) To fix carbon dioxide
Correct Answer: B
Rationale: NADH is an electron carrier that donates its high-energy electrons
to the electron transport chain (ETC). Oxygen is the final electron acceptor.
10. Which of the following is NOT a characteristic of enzymes?
A) They are consumed in the reaction
B) They lower activation energy
C) They are specific to a substrate
D) They are proteins
Correct Answer: A
