ATI RN
Basic principles of pharmacology Questions
Question 1 of 5
A ceramic mortar may be preferable to a glass mortar when
Correct Answer: C
Rationale: A ceramic mortar is preferable when comminution is desired in addition to mixing (C), its rough surface grinding particles effectively (e.g., reducing tablet fragments), unlike smooth glass. Volatile oils (A) risk loss regardless of mortar. Dyes (B) stain ceramics, favoring glass. No option D or original E exists. Ceramic's abrasive texture enhances particle size reduction, critical in extemporaneous compounding for uniform powders, improving dissolution and bioavailability in solid dosage forms.
Question 2 of 5
The earliest evidence that a drug is stored in tissue is
Correct Answer: B
Rationale: A large apparent volume of distribution (V_D) (B) is the earliest evidence of tissue storage, indicating drug distribution beyond plasma into tissues (e.g., digoxin, V_D > 500 L), calculated as dose/plasma concentration. Increased plasma binding (A) reduces V_D. Decreased metabolism (C) affects clearance, not distribution. Side effects (D) or reduced free drug (original E) are downstream. High V_D reflects lipophilicity or tissue affinity, guiding dosing (e.g., loading doses), critical in pharmacokinetics for drugs with extensive tissue uptake.
Question 3 of 5
The initial distribution of a drug into tissue is determined chiefly by the
Correct Answer: A
Rationale: The rate of blood flow to tissue (A) chiefly determines initial drug distribution, as perfusion delivers drug to organs (e.g., brain > fat), seen in anesthetics' rapid onset. GFR (B) affects excretion, not distribution. Stomach emptying (C) influences absorption. Tissue affinity (D) and plasma binding (original E) shape later distribution. Perfusion-limited kinetics prioritize highly vascular tissues, critical for acute therapies, with redistribution (e.g., thiopental) altering duration, a fundamental pharmacokinetic principle.
Question 4 of 5
All of the following carbohydrates are considered to be polysaccharides except
Correct Answer: D
Rationale: Maltose (D) is not a polysaccharide; it's a disaccharide (glucose-glucose), hydrolyzed to monosaccharides, unlike polysaccharides heparin (A, anticoagulant), starch (B, plant storage), and glycogen (C, animal storage), which are large, branched polymers. Cellulose (original E) is also a polysaccharide. Maltose's smaller size, formed during starch digestion, contrasts with polysaccharides' complexity, impacting absorption speed and therapeutic use (e.g., heparin's long-acting effects), key in carbohydrate pharmacology.
Question 5 of 5
Bacteria that grow at temperatures as high as 55°C are known as
Correct Answer: B
Rationale: Thermophiles (B) grow at high temperatures (up to 55°C or more), thriving in hot environments (e.g., Thermus aquaticus). Psychrophiles (A) prefer cold. Mesophiles (C) grow at moderate (e.g., 37°C). Auxotrophs (D) require specific nutrients, unrelated to temperature. No original E. Thermophiles' heat-stable enzymes (e.g., Taq polymerase) revolutionized biotech, indirectly aiding pharmacology via PCR in drug development, distinct from human-pathogenic mesophiles.