(a(i))[2]
Fig. 1.1 presents four arthropods. State two visible features in Fig. 1.1 that are shared by all arthropods.
(a(ii))[2]
Fig. 1.2 is a dichotomous key for the arthropods shown in Fig. 1.1. Complete Fig. 1.2 by entering suitable statements in box 2 to identify species B and in box 3 to distinguish species C from A.
(b(i))[1]
State one feature visible in Fig. 1.3 that shows T. grallator is an arachnid.
(b(ii))[3]
Scientists think that the pattern on the bodies of the spiders is an adaptive feature. Explain the term adaptive feature with reference to this pattern.
(c)[2]
Explain how DNA extracted from spider webs can be used to identify different species.
(d)[3]
State three reasons why animal species such as spiders become endangered.