The body cavity of a cockroach is also called:

The blood of a cockroach does not contain any respiratory pigment. This means that .........

The heart of a cockroach is ...... .

Explain the nervous system of a cockroach.

In cockroach,which of the following is the principal motor centre?

Statement-$I$ :- Heart of cockroach consists of an elongated muscular tube lying along the mid-dorsal line of the thorax and abdomen.
Statement-$II$ :- In cockroach,the opening of the spiracles is regulated by the sphincters.