MCQ Collection
opra MCQs
Practice opra questions with answers and explanations.
Choose an option to check your answer.
A.
25
B.
6.25
C.
50
D.
12.5
Show Answer
Correct Answer: D. 12.5
Explanation:
After three half-lives, (1/2)^3=12.5%.
Choose an option to check your answer.
A.
0.1
B.
1.0
C.
4.8
D.
10.0
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Correct Answer: D. 10.0
Explanation:
For a weak acid, [A−]/[HA]=10^(pH−pKa).
Choose an option to check your answer.
A.
Bactericidal agents cannot have resistance.
B.
Both terms mean viral inactivation.
C.
Bacteriostatic agents always destroy spores.
D.
Bactericidal activity kills susceptible bacteria, whereas bacteriostatic activity inhibits growth.
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Correct Answer: D. Bactericidal activity kills susceptible bacteria, whereas bacteriostatic activity inhibits growth.
Explanation:
Bactericidal activity kills susceptible bacteria, whereas bacteriostatic activity inhibits growth.
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A.
Phase I reactions occur only outside the body.
B.
Phase I reactions commonly introduce or expose functional groups through oxidation, reduction or hydrolysis.
C.
Phase I always produces an inactive metabolite.
D.
Phase I is limited to renal filtration.
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Correct Answer: B. Phase I reactions commonly introduce or expose functional groups through oxidation, reduction or hydrolysis.
Explanation:
Phase I reactions commonly introduce or expose functional groups through oxidation, reduction or hydrolysis.
Choose an option to check your answer.
A.
231.6
B.
99.2
C.
84.0
D.
43.2
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Correct Answer: D. 43.2
Explanation:
Use fraction remaining=e^(−kt).
Choose an option to check your answer.
A.
A randomised controlled design reduces allocation bias and supports causal inference when well conducted.
B.
A case report proves population causality.
C.
Randomisation guarantees zero measurement error.
D.
Blinding always increases sample size.
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Correct Answer: A. A randomised controlled design reduces allocation bias and supports causal inference when well conducted.
Explanation:
A randomised controlled design reduces allocation bias and supports causal inference when well conducted.
Choose an option to check your answer.
A.
It must be 100% when specificity is above 50%.
B.
Positive predictive value depends on disease prevalence as well as test performance.
C.
It is independent of prevalence.
D.
It is always equal to sensitivity.
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Correct Answer: B. Positive predictive value depends on disease prevalence as well as test performance.
Explanation:
Positive predictive value depends on disease prevalence as well as test performance.
Choose an option to check your answer.
A.
It prevents every adverse effect.
B.
It is identical to an intravenous bolus.
C.
A depot formulation can prolong drug release and reduce dosing frequency.
D.
It guarantees immediate peak concentration.
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Correct Answer: C. A depot formulation can prolong drug release and reduce dosing frequency.
Explanation:
A depot formulation can prolong drug release and reduce dosing frequency.
Choose an option to check your answer.
A.
2.81
B.
0.356
C.
4.81
D.
27522
Show Answer
Correct Answer: A. 2.81
Explanation:
Concentration=amount/volume.
Choose an option to check your answer.
A.
0.059
B.
17.0
C.
1700.0
D.
34.0
Show Answer
Correct Answer: B. 17.0
Explanation:
Apply AUC=F×Dose/CL.
Choose an option to check your answer.
A.
6.25
B.
12.5
C.
50
D.
25
Show Answer
Correct Answer: B. 12.5
Explanation:
After three half-lives, (1/2)^3=12.5%.
Choose an option to check your answer.
A.
It always raises the maximal response.
B.
It irreversibly increases efficacy.
C.
A competitive antagonist usually shifts the agonist concentration–response curve to the right without reducing the maximal response.
D.
It removes the need for agonist binding.
Show Answer
Correct Answer: C. A competitive antagonist usually shifts the agonist concentration–response curve to the right without reducing the maximal response.
Explanation:
A competitive antagonist usually shifts the agonist concentration–response curve to the right without reducing the maximal response.
