The following are True concerning diffusion of drugs across cell membranes EXCEPT:

Correct Answer: C

Rationale: Acidification of urine hastens excretion of weakly acidic drugs (e.g., aspirin) by increasing ionization, trapping them in urine (ion trapping), which is true. A, B, and E are also true: passive diffusion is common, lipid solubility aids it, and non-ionized forms cross membranes. However, D is false:aspirin (pKa ~3.5) is mostly ionized in the stomach (pH ~2), not non-ionized, due to pH < pKa. Thus, C is the exception.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.