Gce Model Questions Vol1 2022 Biology Question 37

Practice objective / multiple choice question 37 from the 2022 Gce Model Questions Vol1 Biology examination.

Gce Model Questions Vol1 2022 Biology Objective / Multiple Choice Hard Difficulty
Question 37 GCE_MODEL_QUESTIONS_VOL1 • 2022 • BIOLOGY • objective

A bacterial infection starts with 1.0×10⁶ organisms. In the absence of antibiotic the population doubles every 3 h. An antibiotic is given at 0 h, 8 h and 16 h. Each dose gives an immediate peak plasma concentration of 10 µg·mL⁻¹ which then decays exponentially with a half‑life of 6 h (concentration at time t after a dose is 10·2^{‑t/6} µg·mL⁻¹). The drug is effective while the total plasma concentration exceeds 2 µg·mL⁻¹; during each effective hour the bacterial count is reduced by 70 % (multiplied by 0.3). When the concentration is ≤2 µg·mL⁻¹ the bacteria grow, doubling every 3 h (growth factor per hour = 2^{1/3}). Determine whether the infection is cleared (bacterial count <10³) after 24 h.

Answer Options

A. Yes, the infection is cleared (final count ≈5.0×10², just below 10³).
B. No, the infection persists (final count ≈3.5×10³, slightly above 10³).
Correct Answer C. Yes, the infection is cleared (final count ≈2.8×10⁻⁷, far below 10³).
D. No, the infection is not cleared (final count ≈1.2×10⁴, above 10³).
Correct Answer
C
Correct Option:
Yes, the infection is cleared (final count ≈2.8×10⁻⁷, far below 10³).

About This Question

This is Gce Model Questions Vol1 2022 Biology Question 37. It is one of the objective questions from the 2022 Gce Model Questions Vol1 Biology examination.

Difficulty level: Hard .

View More Gce Model Questions Vol1 2022 Biology Questions More Gce Model Questions Vol1 Practice Questions Back to Questions

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Chat with Support