Which of the following does not participate in excretion in cockroach?

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.

Which of the following parts is not associated with the nerve ring in a cockroach?

In cockroach,nephrocytes are concerned with

Describe the male reproductive system of a cockroach.

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.