In a cockroach,the grinding of food takes place in the ........?

Identify the location and function of the following glands in cockroaches:
$(i)$ Conglobate gland
$(ii)$ Collateral gland

Refer to the given figure of the female reproductive system of a cockroach and identify the correct labels (marked as $1, 2, 3$ and $4$) which are collectively called the genital pouch.

Identify $X, Y$ and $Z$ in the given figure of the male reproductive system of a cockroach.

Which of the following statements is incorrect?

Explain the nervous system of a cockroach.