Disc-Diffusion - GCSE Biology Definition

Disc-Diffusion is a method used to test how effective antibiotics are against bacteria. In this experiment, small paper discs soaked with different antibiotics are placed on a petri dish that has been spread with bacteria. As the antibiotics seep into the surrounding area, they stop the bacteria from growing. This creates clear circles around the discs called 'zones of inhibition'. By measuring these zones, scientists can see which antibiotics work best against the bacteria, which is important for treating infections. This method helps us understand how bacteria can become resistant to antibiotics and why it's important to use them carefully.