DP Chemistry (last assessment 2024)

Test builder »

Question 19M.3.sl.TZ1.b

Select a Test
Date May 2019 Marks available [Maximum mark: 2] Reference code 19M.3.sl.TZ1.b
Level sl Paper 3 Time zone TZ1
Command term Explain Question number b Adapted from N/A
b.
[Maximum mark: 2]
19M.3.sl.TZ1.b

This question is about antiviral drugs.

Anti-HIV drugs, such as zidovudine, often become less effective over time.

Explain the development of resistant virus strains in the presence of antiviral drugs.

[2]

Markscheme

viruses undergo «rapid» mutation  [✔]

mutation causes a change in viral protein
OR
 drug to no longer binds to virus  [✔]

 

Note: Accept “rapid reproduction «allows resistant viruses to multiply»”.

Examiners report

Another question where well argued responses were rare, though many students gained credit for mentioning the ease of mutation and the speed of reproduction of viruses.

Syllabus sections