Explain the nervous system of cockroach

Explanation

The nervous system of cockroach consists of a nerve ring and a ganglionated double ventral nerve cord, sub-oesophageal ganglion circum-oesophageal connectives and double ventral nerve cord (see figure). The nervering is present around the oesophagus in the head capsule and is formed by the supra-oesophagial ganglion called the 'brain' The brain is mainly a sensory and an endocrine centre and lies above the oesophagus. Sub-oesophageal ganglion is the motor centre that controls the movements of the mouth parts, legs and wings. It lies below the oesophagus and formed by the fusion of the paired gangalia of mandibular, maxillary and labial segments of the head. A pair of circum-oesophageal connectives is present around the oesophagus, connecting the supraoesophageal ganglia with the sub-oesophageal ganglion. The double ventral nerve cord is solid, ganglionated and arises from the sub-oesophageal ganglion and extends up to the `7^(th)` abdominal segment. Three thoracic ganglia are present, one in each thoracic segment and six abdominal ganglia in the abdomen.