Quiz 3: 30S Protein Synthesis Inhibitors (Tetracyclines &
Aminoglycosides) Advanced Pharmacology NP Board Exam Preparation • 10 Practice Questions & Rationales
1. What is the mechanism of action of Tetracyclines?
A. Irreversible binding to the 50S ribosomal subunit
B. Reversible binding to the 30S ribosomal subunit blocking aminoacyl-tRNA
C. Inhibition of bacterial DNA gyrase
D. Disruption of outer cell membrane phospholipids
Correct Answer: B — Tetracyclines enter bacteria and reversibly bind to the 30S ribosomal subunit, preventing attachment of
aminoacyl-tRNA to the mRNA-ribosome complex.
2. Why are Tetracyclines contraindicated in pregnant women and children under 8 years of age?
A. High risk of Gray Baby Syndrome
B. Deposition in calcified tissues causing permanent tooth discoloration and bone growth suppression
C. Severe acute renal failure and ATN
D. Tendon rupture and cartilage degradation
Correct Answer: B — Tetracyclines chelate calcium and deposit in calcifying teeth and bones, leading to permanent enamel
discoloration and temporary growth stunting.
3. Which tetracycline derivative is preferred in patients with severe renal impairment because it is eliminated via the
biliary system into feces?
A. Tetracycline
B. Demeclocycline
C. Doxycycline
D. Sarecycline
Correct Answer: C — Doxycycline is eliminated primarily via bile into feces and does not require dosage adjustments in renal
insufficiency.
4. What instruction must be given to patients taking oral Tetracycline to prevent treatment failure?
A. Take with a large glass of whole milk
B. Avoid co-administration with dairy, antacids, or iron supplements
C. Take immediately before bedtime without water
D. Double the dose if taken with calcium-fortified juice
Correct Answer: B — Divalent and trivalent cations (Ca2+, Mg2+, Fe2+, Al3+) in dairy and antacids form nonabsorbable chelates
with tetracyclines, reducing absorption.
NP Advanced Pharmacology Exam Practice Questions Page 1 of 3
Aminoglycosides) Advanced Pharmacology NP Board Exam Preparation • 10 Practice Questions & Rationales
1. What is the mechanism of action of Tetracyclines?
A. Irreversible binding to the 50S ribosomal subunit
B. Reversible binding to the 30S ribosomal subunit blocking aminoacyl-tRNA
C. Inhibition of bacterial DNA gyrase
D. Disruption of outer cell membrane phospholipids
Correct Answer: B — Tetracyclines enter bacteria and reversibly bind to the 30S ribosomal subunit, preventing attachment of
aminoacyl-tRNA to the mRNA-ribosome complex.
2. Why are Tetracyclines contraindicated in pregnant women and children under 8 years of age?
A. High risk of Gray Baby Syndrome
B. Deposition in calcified tissues causing permanent tooth discoloration and bone growth suppression
C. Severe acute renal failure and ATN
D. Tendon rupture and cartilage degradation
Correct Answer: B — Tetracyclines chelate calcium and deposit in calcifying teeth and bones, leading to permanent enamel
discoloration and temporary growth stunting.
3. Which tetracycline derivative is preferred in patients with severe renal impairment because it is eliminated via the
biliary system into feces?
A. Tetracycline
B. Demeclocycline
C. Doxycycline
D. Sarecycline
Correct Answer: C — Doxycycline is eliminated primarily via bile into feces and does not require dosage adjustments in renal
insufficiency.
4. What instruction must be given to patients taking oral Tetracycline to prevent treatment failure?
A. Take with a large glass of whole milk
B. Avoid co-administration with dairy, antacids, or iron supplements
C. Take immediately before bedtime without water
D. Double the dose if taken with calcium-fortified juice
Correct Answer: B — Divalent and trivalent cations (Ca2+, Mg2+, Fe2+, Al3+) in dairy and antacids form nonabsorbable chelates
with tetracyclines, reducing absorption.
NP Advanced Pharmacology Exam Practice Questions Page 1 of 3
