| Date | May 2018 | Marks available | 1 | Reference code | 18M.1.SL.TZ2.27 |
| Level | Standard level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | Question number | 27 | Adapted from | N/A |
Question
Florey and Chain injected four mice with Streptococcus bacteria and then penicillin and all four mice recovered from the infection. What would be essential to show that penicillin caused their recovery?
A. A control group that was infected but not treated with penicillin
B. Experiments to test for effects of penicillin on other bacteria
C. Experiments to test for effects of different dosages of penicillin in mice
D. Determination of the chemical structure of penicillin
Markscheme
A
Examiners report
[N/A]
