Question

Maximum number of ganglia are present in Cockroach in ______________.

• A. Neck
• B. Thorax
• C. Abdomen
• D. Head

Answer 1

The correct option is C Abdomen

Cockroach (Periplaneta americana) has in total 9 ganglia in number.Out of these ganglia, 3 are present in the thorax and 6 are present in the abdomen.These six ganglia are present in the 1st,2nd,3rd,4th,5th and 7th segment of the nervous system of the cockroach.Each ganglion of the nerve cord is formed by the fusion of two ganglia except the ganglion in the 7th segment. The ganglion in the 7th abdominal segment is the largest of all the abdominal ganglia and probably formed by the fusion of 3 pairs of ganglia.

So, the correct answer is 'Abdomen'.