(a(i))[2]
Identify the letters of two labelled parts in Fig. 4.1 that contain DNA.
(a(ii))[1]
State the identity of the structure labelled A in Fig. 4.1.
(a(iii))[1]
State the role of the part labelled D in Fig. 4.1.
(b)[2]
Some bacteria cause transmissible diseases. Describe what transmissible disease means.
(c)[1]
Disease can be transmitted indirectly or directly. State one method by which disease can be transmitted directly.
(d)[4]
Using this information and your knowledge, suggest methods for preventing the spread of food poisoning caused by Salmonella bacteria.