Question

If the head of cockroach is removed, it may live for few days because

• A. the head holds a small proportion of a nervous system while the rest is situated along the ventral part of its body
• B. the head holds a 1/3rd of a nervous system while the rest is situated along the dorsal part of its body
• C. the supra-oesophageal ganglia of the cockroach are situated in ventral part of abdomen
• D. the cockroach does not have nervous system

Answer 1

The correct option is A the head holds a small proportion of a nervous system while the rest is situated along the ventral part of its body

Nervous system consists of nerve ring and ventral double nerve cord. Nerve ring is situated oesophegeal area. Head contain only branches of ganglia so there is no major part of nervous system in head region. So, even if the head portion is removed, it may live for few days because the head holds a small proportion of a nervous system while the rest is situated along the ventral part of its body.