Last Updated Sep 26, 2025

Investigating antibiotics & antiseptics Simplified Revision Notes for GCSE Edexcel Biology

Revision notes with simplified explanations to understand Investigating antibiotics & antiseptics quickly and effectively.

Learn about Investigating antibiotics & antiseptics for your GCSE Biology Exam. This Revision Note includes a summary of Investigating antibiotics & antiseptics for easy recall in your Biology exam

258+ students studying

Investigating antibiotics & antiseptics Quizzes

Test your knowledge with quizzes.

Investigating antibiotics & antiseptics Flashcards

Practice with bite-sized questions.

Investigating antibiotics & antiseptics Questions by Topic

Prepare with real exam question.

Print Free PDF

Investigating antibiotics & antiseptics

Comparing the sizes of the inhibition zones compares the effectiveness of different antibiotics (or antiseptics or plant extracts)

infoNote

The effectiveness of the selected antibiotic or antiseptic can be quantified using the formula for the area of a circle, πr². Using the diagram below:

1. For π, use the value 3.14. This value may vary slightly in specific questions.
2. Measure the diameter of the zone of inhibition and divide it by 2 to obtain the radius (e.g., 10 ÷ 2 = 5 mm).
3. Apply the equation: πr²

• For example: 3.14 × 5² = 3.14 × 25 = 78.5 square millimeters.

Calculate the sizes of the inhibition zones to compare results

infoNote

The larger the inhibition zone around the disc the more bacteria killed so the more effective the antibiotic is against the bacteria

Only available for registered users.

Sign up now to view the full note, or log in if you already have an account!

Sign up with GoogleSign up with Apple

500K+ Students Use These Powerful Tools to Master Investigating antibiotics & antiseptics For their GCSE Exams.

Enhance your understanding with flashcards, quizzes, and exams—designed to help you grasp key concepts, reinforce learning, and master any topic with confidence!

Other Revision Notes related to Investigating antibiotics & antiseptics you should explore

Discover More Revision Notes Related to Investigating antibiotics & antiseptics to Deepen Your Understanding and Improve Your Mastery