(a)[3]
Describe the function of Golgi bodies in secretory cells, such as the salivary gland cells of aphids.
(b(i))[2]
Explain why secretory cells contain many mitochondria.
(b(ii))[2]
Mitochondria are partly under nuclear control, yet they can also operate on their own. Suggest the features of mitochondria that make this possible without the nucleus.
(c(i))[3]
Describe the structure found in a typical virus.
(c(ii))[1]
Suggest how viruses can move from one plant cell to another without crossing membranes.