(N/A) $\Rightarrow$ The nervous system of the cockroach consists of a series of fused,segmentally arranged ganglia joined by paired longitudinal connectives on the ventral side.
$\Rightarrow$ Three ganglia lie in the thorax,and six in the abdomen.
$\Rightarrow$ The nervous system of the cockroach is spread throughout the body. The head holds a small part of the nervous system,while the rest is situated along the ventral part of the body. Therefore,if the head of a cockroach is cut off,it will still live for as long as one week.
$\Rightarrow$ In the head region,the brain is represented by the supra-oesophageal ganglion,which supplies nerves to the antennae and compound eyes.