Four plantations each contained 200 healthy ash trees at the start of an investigation. The plantations were monitored for one year.
Managers used different control programmes, as shown in the table. Only the original 200 trees in each plantation were monitored for disease development. Any ash plants subsequently brought into a plantation were excluded from the reported counts.
| Movement of ash plants into the plantation | Infected ash trees removed | Number of the original 200 trees that developed ash dieback |
|---|---|---|
| allowed | no | 74 |
| allowed | yes | 31 |
| prevented | no | 42 |
| prevented | yes | 12 |
A forestry officer recommends preventing the movement of ash plants and removing infected ash trees.
Explain how the results and the biology of ash dieback support this recommendation.
112 exam-style questions on Edexcel GCSE Biology 5.1 Health and communicable disease, covering 5.1.1 Communicable and non-communicable diseases, 5.1.2 Disease susceptibility interactions, 5.1.3 Pathogens as disease-causing organisms, 5.1.4 Common infections, 5.1.5 Spread and prevention of pathogens, 5.1.6 Lifecycle of a virus, and 5.1.7 Spread and prevention of STIs. Each one has a worked solution and a mark scheme showing where the marks go.