List salient features of insects.

Explanation

Insecta is the largest class of animals. Insecta has the following characters :
(i) The body is divisible into head, thorax and abdomen.
(ii) Head bears two antennae, two compound eyes and mouth parts for various modes of feeding.
(iii) Thorax bear three pairs of legs. It also bears one or two pairs of wings.
(iv) Respiration occurs with the help of tracheae.
(v) Excretion takes place by malpighian tubules.
(vi) Insects are unisexual.