A scientist tests whether a leaf cuticle acts mainly as a physical barrier. Spores infect leaves when placed beneath an intact cuticle, but rarely infect leaves when placed on its surface.
Which explanation is best supported?
bypassing the cuticle allows access to tissue that can be infected
bypassing the cuticle causes the spores to lose their ability to infect
the intact cuticle makes the tissue beneath it resistant to all infection
the intact cuticle kills the spores only after they have entered the tissue
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.