A student compares two samples containing the same starting number of bacteria. One sample contains active lysozyme. The other contains lysozyme that has been inactivated.
More bacteria survive in the sample with inactive lysozyme. Which explanation accounts for this difference?
active lysozyme thickens bacterial cell walls, reducing survival
active lysozyme breaks down bacterial cell walls, reducing survival
active lysozyme moves bacteria towards the throat, reducing survival
active lysozyme traps bacteria in a waxy coating, reducing survival
45 exam-style questions on Edexcel GCSE Biology 5.2 Plant and body defences, covering 5.2.1 Physical plant defences, 5.2.2 Chemical plant defences, 5.2.3 Detecting plant diseases, and 5.2.4 Human physical and chemical defences. Each one has a worked solution and a mark scheme showing where the marks go.