In cockroach,the number of ganglia are

Which accessory digestive gland is found in a cockroach?

Ecdysone is produced by

In cockroaches,during the digestion of food,the enzyme cellulase is synthesized by:

Consider the following statements regarding cockroach and mark the correct option.
$(i)$ Head is formed by the fusion of $6$ segments.
$(ii)$ Mouth parts are biting and chewing type.
$(iii)$ Crop is the part of midgut.

The figure given below shows the alimentary canal of a cockroach with a few structures labelled as $1, 2, 3$ and $4$. Identify the structure which is also called proventriculus and helps in grinding the food particles.