BIOD 102 Portage Learning - Lab 5 Exam
(Pharmacokinetics) (2026/2027)
Section 1: Pharmacokinetic Parameter Calculations
Q1: A 750 mg dose of Drug A is administered as an intravenous bolus. The concentration
immediately after injection (C0) is 15 mg/L. What is the Volume of Distribution (Vd)?
A. 0.02 L
B. 50 L [CORRECT]
C. 100 L
D. 11.25 L
Correct Answer: B
Rationale: Vd is calculated as Dose / C0. Calculation: 750 mg / 15 mg/L = 50 L.
Q2: A researcher plots plasma concentration data on a semi-logarithmic graph. The slope of the
terminal straight line is calculated to be -0.231 hours^-1. What is the elimination rate constant
(ke)?
A. -0.231 hours^-1
B. 0.231 hours^-1 [CORRECT]
C. 0.693 hours^-1
D. 0.333 hours^-1
Correct Answer: B
Rationale: The elimination rate constant (ke) is the absolute value (positive value) of the slope
found on a semi-log plot of concentration versus time.
.
,Q3: Using the elimination rate constant (ke) from Question 2 (0.231 hours^-1), calculate the
half-life (t1/2) of the drug.
A. 0.693 hours
B. 1.5 hours
C. 3.0 hours [CORRECT]
D. 3.33 hours
Correct Answer: C
Rationale: Half-life is calculated as t1/2 = 0.693 / ke. Calculation: 0..231 hours^-1 = 3.0
hours.
Q4: A patient has a Volume of Distribution (Vd) of 40 L and an elimination rate constant (ke) of
0.1 hours^-1. Calculate the Total Body Clearance (CL) in L/hour.
A. 4.0 L/hour [CORRECT]
B. 0.25 L/hour
C. 400 L/hour
D. 40.1 L/hour
Correct Answer: A
Rationale: Clearance is the product of the elimination rate constant and volume of
distribution: CL = ke × Vd. Calculation: 0.1 hours^-1 × 40 L = 4.0 L/hour.
Q5: A drug has a half-life of 8 hours. Approximately how long will it take to reach 93.75% of
steady state (approximately 4 half-lives) if administered via continuous infusion?
A. 8 hours
B. 16 hours
C. 24 hours
D. 32 hours [CORRECT]
Correct Answer: D
Rationale: It takes 4 to 5 half-lives to reach steady state. Calculation: 4 half-lives × 8 hours/half-
life = 32 hours.
.
, Q6: The plasma concentration of a drug drops from 50 mg/L to 12.5 mg/L in 12 hours. How
many half-lives have passed, and what is the half-life?
A. 2 half-lives; 6 hours [CORRECT]
B. 3 half-lives; 4 hours
C. 4 half-lives; 3 hours
D. 1 half-life; 12 hours
Correct Answer: A
Rationale: 50 to 25 mg/L is one half-life; 25 to 12.5 mg/L is a second half-life. Total drop
represents 2 half-lives. 12 hours / 2 = 6 hours per half-life.
Q7: Calculate the Loading Dose required to achieve a target concentration (Ctarget) of 6 mg/L
immediately. The patient has a Volume of Distribution (Vd) of 35 L and the drug is administered
intravenously (F = 1).
A. 5.83 mg
B. 210 mg [CORRECT]
C. 41.67 mg
D. 35 mg
Correct Answer: B
Rationale: Loading Dose = (Ctarget × Vd) / F. Calculation: (6 mg/L × 35 L) / 1 = 210 mg.
Q8: You need to calculate an oral Maintenance Dose. The desired average steady-state
concentration is 10 mg/L. The drug has a Clearance (CL) of 5 L/hour and a bioavailability (F) of
0.8. The dosing interval (τ) is 12 hours.
A. 600 mg
B. 480 mg
C. 750 mg [CORRECT]
D. 62.5 mg
Correct Answer: C
.
(Pharmacokinetics) (2026/2027)
Section 1: Pharmacokinetic Parameter Calculations
Q1: A 750 mg dose of Drug A is administered as an intravenous bolus. The concentration
immediately after injection (C0) is 15 mg/L. What is the Volume of Distribution (Vd)?
A. 0.02 L
B. 50 L [CORRECT]
C. 100 L
D. 11.25 L
Correct Answer: B
Rationale: Vd is calculated as Dose / C0. Calculation: 750 mg / 15 mg/L = 50 L.
Q2: A researcher plots plasma concentration data on a semi-logarithmic graph. The slope of the
terminal straight line is calculated to be -0.231 hours^-1. What is the elimination rate constant
(ke)?
A. -0.231 hours^-1
B. 0.231 hours^-1 [CORRECT]
C. 0.693 hours^-1
D. 0.333 hours^-1
Correct Answer: B
Rationale: The elimination rate constant (ke) is the absolute value (positive value) of the slope
found on a semi-log plot of concentration versus time.
.
,Q3: Using the elimination rate constant (ke) from Question 2 (0.231 hours^-1), calculate the
half-life (t1/2) of the drug.
A. 0.693 hours
B. 1.5 hours
C. 3.0 hours [CORRECT]
D. 3.33 hours
Correct Answer: C
Rationale: Half-life is calculated as t1/2 = 0.693 / ke. Calculation: 0..231 hours^-1 = 3.0
hours.
Q4: A patient has a Volume of Distribution (Vd) of 40 L and an elimination rate constant (ke) of
0.1 hours^-1. Calculate the Total Body Clearance (CL) in L/hour.
A. 4.0 L/hour [CORRECT]
B. 0.25 L/hour
C. 400 L/hour
D. 40.1 L/hour
Correct Answer: A
Rationale: Clearance is the product of the elimination rate constant and volume of
distribution: CL = ke × Vd. Calculation: 0.1 hours^-1 × 40 L = 4.0 L/hour.
Q5: A drug has a half-life of 8 hours. Approximately how long will it take to reach 93.75% of
steady state (approximately 4 half-lives) if administered via continuous infusion?
A. 8 hours
B. 16 hours
C. 24 hours
D. 32 hours [CORRECT]
Correct Answer: D
Rationale: It takes 4 to 5 half-lives to reach steady state. Calculation: 4 half-lives × 8 hours/half-
life = 32 hours.
.
, Q6: The plasma concentration of a drug drops from 50 mg/L to 12.5 mg/L in 12 hours. How
many half-lives have passed, and what is the half-life?
A. 2 half-lives; 6 hours [CORRECT]
B. 3 half-lives; 4 hours
C. 4 half-lives; 3 hours
D. 1 half-life; 12 hours
Correct Answer: A
Rationale: 50 to 25 mg/L is one half-life; 25 to 12.5 mg/L is a second half-life. Total drop
represents 2 half-lives. 12 hours / 2 = 6 hours per half-life.
Q7: Calculate the Loading Dose required to achieve a target concentration (Ctarget) of 6 mg/L
immediately. The patient has a Volume of Distribution (Vd) of 35 L and the drug is administered
intravenously (F = 1).
A. 5.83 mg
B. 210 mg [CORRECT]
C. 41.67 mg
D. 35 mg
Correct Answer: B
Rationale: Loading Dose = (Ctarget × Vd) / F. Calculation: (6 mg/L × 35 L) / 1 = 210 mg.
Q8: You need to calculate an oral Maintenance Dose. The desired average steady-state
concentration is 10 mg/L. The drug has a Clearance (CL) of 5 L/hour and a bioavailability (F) of
0.8. The dosing interval (τ) is 12 hours.
A. 600 mg
B. 480 mg
C. 750 mg [CORRECT]
D. 62.5 mg
Correct Answer: C
.
