1.1. Higher Tier only

Chalara Ash Dieback is a fungal disease affecting ash trees. 

Cases of Ash Dieback were reported in a region of Devon. The affected trees were cut down to avoid infection of nearby ash trees. It was also recommended that all trees within a 30 km radius of the infected trees were checked for infection.

(i) Describe the signs that would indicate that an ash tree has been infected with Chalara Ash Dieback.

(1)

(ii) Explain how Chalara Ash Dieback could infect trees as far as 30 km away from an infected tree. (2)

1.2. Figure 1 shows the structure of a virus particle.

Figure 1

(i) Complete the table below to identify the structures labelled in Figure 5.

(3)

(ii) Describe the function of component B.

(2)

1.3. Explain why a virus could be considered parasitic.