Anal cerci occur in

Which part of the cockroach is well-developed in both the endoskeleton and exoskeleton?

Explain the head of a cockroach.

Externally,male and female cockroaches can be distinguished by ............ .

Which of the following statement$(s)$ is/are correct?
$(i)$ Cockroaches are brown or black bodied animals that are included in class $Insecta$ of phylum $Arthropoda$.
$(ii)$ Males bear a pair of short,thread-like anal styles which are absent in females.
$(iii)$ The heart of a cockroach consists of an elongated muscular tube lying along the mid-dorsal line of the thorax and abdomen.
$(iv)$ The nymph grows by moulting about $13$ times to reach the adult form.

$Periplaneta$ shows