(a)[1]
State one characteristic used to identify vertebrates.
(b(i))[2]
State the vertebrate group that emus belong to and give one visible feature of this group shown in Fig. 1.1.
(b(ii))[2]
State the vertebrate group that crocodiles belong to and give one visible feature of this group shown in Fig. 1.1.
(b(iii))[3]
Give evidence from Fig. 1.1 that supports and opposes classifying the duck-billed platypus as a mammal.
(c)[2]
State the names of these two groups of vertebrates.