ATI RN
Chapter 2 pharmacologic principles Questions
Question 1 of 5
The sugar that is inherent in the nucleic acids RNA and DNA is
Correct Answer: C
Rationale: Ribose (C) is the sugar in RNA (pentose) and DNA (as deoxyribose), forming the nucleic acid backbone with phosphates and bases. Glucose (A) is metabolic. Sucrose (B) is a disaccharide. Digitoxose (D) is in cardiac glycosides. Maltose (original E) is a disaccharide. Ribose's presence enables RNA/DNA synthesis, targeted by antivirals (e.g., ribavirin), a key structural distinction in molecular biology and pharmacology.
Question 2 of 5
Flurazepam has pKa of 8.2. What percentage of flurazepam will be ionized at a urine pH of 5.2 ?
Correct Answer: B
Rationale: Flurazepam (pKa 8.2), a weak base, is 1% ionized at urine pH 5.2 (B). Henderson-Hasselbalch: pH = pKa + log([B]/[BHâº]); 5.2 = 8.2 + log([B]/[BHâº]), log([B]/[BHâº]) = -3, [B]/[BHâº] = 0.001, so BH⺠(ionized) is 99.9/100.9 ≈ 99%, un-ionized ~1%. Options A (0.1%), C (50%), and D (99%) miscalculate. Option E (original, 99.9%) inverts. This low ionization favors reabsorption, slowing excretion, relevant in benzodiazepine pharmacokinetics and overdose management.
Question 3 of 5
Which of the following radionuclides is generator produced?
Correct Answer: A
Rationale: â¹â¹áµTc (A) is generator-produced, from â¹â¹Mo decay (tâ‚/â‚‚ 66h) in a molybdenum-technetium generator, yielding gamma-emitting Tc-99m (tâ‚/â‚‚ 6h) for imaging (e.g., thyroid scans). ²â°Â¹Tl (B), â¶â·Ga (C), ¹³³Xe (D), and ¹²³I (original E) are
Question 4 of 5
A hospitalized patient with systemic candidiasis is receiving intravenous antifungal medications. He also has hepatic and renal insufficiency. Which of the following drug administration schemes would allow for the most steady state amount of drug in the body over a 2-week hospitalization period where medication administration will be necessary?
Correct Answer: A
Rationale: Continuous IV infusion (A) provides the most steady-state drug levels over 2 weeks in a patient with systemic candidiasis and hepatic/renal insufficiency. It delivers a constant rate, compensating for impaired clearance (e.g., antifungals like amphotericin), avoiding peaks/troughs of intermittent dosing (B, C, D, E original). Weekly (B) or twice-weekly (E) injections risk subtherapeutic gaps; daily (C) or twice-daily (D) cause fluctuations. Steady-state maintenance is critical in severe infections with compromised metabolism/excretion, ensuring consistent therapeutic levels, reducing toxicity, and optimizing outcomes in critical care.
Question 5 of 5
A 59-year-old female with diabetes presents to her primary care physician for routine follow-up. Her current medications include insulin. Her fasting blood sugars are in the range of 80 to $120 \mathrm{mg} / \mathrm{dL}$. The intracellular effects of this medication are likely caused by which of the following mechanisms of action?
Correct Answer: C
Rationale: Insulin's intracellular effects occur via protein phosphorylation (C). Binding its tyrosine kinase receptor, insulin triggers autophosphorylation, activating cascades (e.g., PI3K-Akt) that phosphorylate proteins, promoting glucose uptake (GLUT4 translocation). Ionic changes (A) and membrane potential (B) are ion channel effects. Protein and receptor phosphorylation (D) overcomplicates; receptor phosphorylation initiates, but cellular effects are downstream. Receptor destruction (original E) is false. This mechanism ensures glycemic control (80-120 mg/dL), critical in diabetes management, distinguishing insulin from ionotropic drugs.