Question 20N.3.hl.TZ0.b(ii)
| Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.3.hl.TZ0.b(ii) |
| Level | hl | Paper | 3 | Time zone | TZ0 |
| Command term | Explain | Question number | b(ii) | Adapted from | N/A |
Consider the structures of medicinal molecules in section 37 of the data booklet.
Explain, with reference to the action of penicillin, why new penicillins with different side-chains need to be produced.
[2]
bacterial resistance «to older penicillins/antibiotics» ✔
prevent penicillinase/beta-lactamase/enzyme in bacterium to deactivate/open penicillin/beta-lactam ring ✔
Accept “antibiotic resistant bacteria” but not “antibiotic resistance” for M1.
Accept “reduce allergic reactions from penicillin” for M2.
Award [1 max] for “increased efficiency” OR “increased stability in GIT”.
Do not accept “bacteria develop tolerance”.
This question was well answered though many lost M1 for stating "antibiotic resistance" instead of mentioning "bacterial resistance".
