The term 'zones of inhibition' refers to the clear, circular areas that appear around antibiotic discs placed on an agar plate in a laboratory experiment. These zones show where bacteria have not been able to grow due to the antibiotic’s effects. The size of the zone of inhibition indicates how effective an antibiotic is against a particular type of bacteria — a larger zone area means the antibiotic is more effective. In GCSE Biology, this concept helps students understand how antibiotics work and how bacterial resistance can be tested.
Examiner-written GCSE Biology revision resources that improve your grades 2x
- Written by expert teachers and examiners
- Aligned to exam specifications
- Everything you need to know, and nothing you don’t
Share this article
written revision resources that improve your