In cockroach,the ootheca is produced by the secretion of:

Explain the structure of the brain and neurons in a cockroach.

Which of the following organisms possesses high and regular blood pressure?

In a cockroach,from where do the hepatic caecae arise?

Answer in one word or one line. Where do you find Malpighian tubules?

Read the following statements and choose the correct option:
$(A)$ The cockroach nervous system consists of a series of fused,segmentally arranged ganglia.
$(B)$ Ganglia are joined in the cockroach by paired longitudinal connectives on the ventral side.
$(C)$ The nervous system is present on the dorsal side of the cockroach.
$(D)$ In the cockroach,the total number of ganglia is nine.