Question 16
HChalara ash dieback is a disease of ash trees. Scientists recorded the percentage of ash trees showing leaf loss at different distances from the first tree found with the disease.
The Figure shows the results in year 1 and in year 3.
Figure
a.[2]
Describe the distribution of affected trees in year 1.
b.[3]
Explain how the results show that the leaf loss is caused by a pathogen rather than by an environmental factor.
c.[2]
Describe how scientists could confirm that the leaf loss is caused by the Chalara fungus.
5.2 Plant and body defences Questions
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.